{
"cells": [
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"# 5D Kerr-AdS spacetime with a Nambu-Goto string\n",
"\n",
"## Case b = n a"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"This [SageMath](https://www.sagemath.org/) notebook is relative to the article *Heavy quarks in rotating plasma via holography* by Anastasia A. Golubtsova, Eric Gourgoulhon and Marina K. Usova, [arXiv:2107.11672](https://arxiv.org/abs/2107.11672).\n",
"\n",
"The involved differential geometry computations are based on tools developed through the [SageManifolds](https://sagemanifolds.obspm.fr) project."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"*NB:* a version of SageMath at least equal to 9.1 is required to run this notebook:"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/plain": [
"'SageMath version 9.3, Release Date: 2021-05-09'"
]
},
"execution_count": 1,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"version()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"First we set up the notebook to display mathematical objects using LaTeX rendering:"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"%display latex"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"Since some computations are quite long, we ask for running them in parallel on 8 cores:"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"Parallelism().set(nproc=8)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"## Spacetime manifold\n",
"\n",
"We declare the Kerr-AdS spacetime as a 5-dimensional Lorentzian manifold:"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"5-dimensional Lorentzian manifold M\n"
]
}
],
"source": [
"M = Manifold(5, 'M', r'\\mathcal{M}', structure='Lorentzian', metric_name='G')\n",
"print(M)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"Let us define **Boyer-Lindquist-type coordinates (rational polynomial version)** on $\\mathcal{M}$, via the method `chart()`, the argument of which is a string expressing the coordinates names, their ranges (the default is $(-\\infty,+\\infty)$) and their LaTeX symbols:"
]
},
{
"cell_type": "code",
"execution_count": 5,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left(\\mathcal{M},(t, r, {\\mu}, {\\phi}, {\\psi})\\right)$$"
],
"text/plain": [
"Chart (M, (t, r, mu, ph, ps))"
]
},
"execution_count": 5,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"BL. = M.chart(r't r:(0,+oo) mu:(0,1):\\mu ph:(0,2*pi):\\phi ps:(0,2*pi):\\psi')\n",
"BL"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"The coordinate $\\mu$ is related to the standard Boyer-Lindquist coordinate $\\theta$ by\n",
"$$ \\mu = \\cos\\theta$$"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The coordinate ranges are"
]
},
{
"cell_type": "code",
"execution_count": 6,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}t :\\ \\left( -\\infty, +\\infty \\right) ;\\quad r :\\ \\left( 0 , +\\infty \\right) ;\\quad {\\mu} :\\ \\left( 0 , 1 \\right) ;\\quad {\\phi} :\\ \\left( 0 , 2 \\, \\pi \\right) ;\\quad {\\psi} :\\ \\left( 0 , 2 \\, \\pi \\right)$$"
],
"text/plain": [
"t: (-oo, +oo); r: (0, +oo); mu: (0, 1); ph: (0, 2*pi); ps: (0, 2*pi)"
]
},
"execution_count": 6,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"BL.coord_range()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Note that contrary to the 4-dimensional case, the range of $\\mu$ is $(0,1)$ only (cf. Sec. 1.2 of [R.C. Myers, arXiv:1111.1903](https://arxiv.org/abs/1111.1903) or Sec. 2 of [G.W. Gibbons, H. Lüb, Don N. Page, C.N. Pope, J. Geom. Phys. **53**, 49 (2005)](https://doi.org/10.1016/j.geomphys.2004.05.001)). In other words, the range of $\\theta$ is $\\left(0, \\frac{\\pi}{2}\\right)$ only. "
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"## Metric tensor\n",
"\n",
"The 4 parameters $m$, $a$, $b$ and $\\ell$ of the Kerr-AdS spacetime are declared as symbolic variables, $a$ and $b$ being the two angular momentum parameters and $\\ell$ being related to the cosmological constant by $\\Lambda = - 6 \\ell^2$:"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left(m, a, b\\right)$$"
],
"text/plain": [
"(m, a, b)"
]
},
"execution_count": 7,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"var('m a b', domain='real')"
]
},
{
"cell_type": "code",
"execution_count": 8,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\ell}$$"
],
"text/plain": [
"l"
]
},
"execution_count": 8,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"var('l', domain='real', latex_name=r'\\ell')"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We assume that $b = n a$:"
]
},
{
"cell_type": "code",
"execution_count": 9,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"n = var('n', domain='real')\n",
"b = n*a"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"Some auxiliary functions:"
]
},
{
"cell_type": "code",
"execution_count": 10,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"keep_Delta = True # change to False to provide explicit expression for Delta_r, Xi_a, etc..."
]
},
{
"cell_type": "code",
"execution_count": 11,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"sig = (1 + r^2*l^2)/r^2\n",
"costh2 = mu^2\n",
"sinth2 = 1 - mu^2\n",
"rho2 = r^2 + a^2*mu^2 + b^2*sinth2\n",
"# Explicit expressions:\n",
"Delta_r_expr = (r^2+a^2)*(r^2+b^2)*sig - 2*m\n",
"Delta_th_expr = 1 - a^2*l^2*costh2 - b^2*l^2*sinth2\n",
"Xi_a_expr = 1 - a^2*l^2\n",
"Xi_b_expr = 1 - b^2*l^2\n",
"if keep_Delta:\n",
" Delta_r = var('Delta_r', latex_name=r'\\Delta_r', domain='real')\n",
" Delta_th = var('Delta_th', latex_name=r'\\Delta_\\theta', domain='real')\n",
" if a == b:\n",
" Xi_a = var('Xi', latex_name=r'\\Xi', domain='real')\n",
" Xi_b = Xi_a\n",
" else:\n",
" Xi_a = var('Xi_a', latex_name=r'\\Xi_a', domain='real')\n",
" Xi_b = var('Xi_b', latex_name=r'\\Xi_b', domain='real')\n",
"else:\n",
" Delta_r = Delta_r_expr\n",
" Delta_th = Delta_th_expr\n",
" Xi_a = Xi_a_expr\n",
" Xi_b = Xi_b_expr"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"The metric is set by its components in the coordinate frame associated with the Boyer-Lindquist-type coordinates, which is the current manifold's default frame. These components can be deduced from\n",
"Eq. (5.22) of the article [S.W. Hawking, C.J. Hunter & M.M. Taylor-Robinson, Phys. Rev. D **59**, 064005 (1999)](https://doi.org/10.1103/PhysRevD.59.064005) (the check of agreement with this equation is performed below):"
]
},
{
"cell_type": "code",
"execution_count": 12,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"G = M.metric()\n",
"tmp = 1/rho2*( -Delta_r + Delta_th*(a^2*sinth2 + b^2*mu^2) + a^2*b^2*sig )\n",
"G[0,0] = tmp.simplify_full()\n",
"tmp = a*sinth2/(rho2*Xi_a)*( Delta_r - (r^2+a^2)*(Delta_th + b^2*sig) )\n",
"G[0,3] = tmp.simplify_full()\n",
"tmp = b*mu^2/(rho2*Xi_b)*( Delta_r - (r^2+b^2)*(Delta_th + a^2*sig) )\n",
"G[0,4] = tmp.simplify_full()\n",
"G[1,1] = (rho2/Delta_r).simplify_full()\n",
"G[2,2] = (rho2/Delta_th/(1-mu^2)).simplify_full()\n",
"tmp = sinth2/(rho2*Xi_a^2)*( - Delta_r*a^2*sinth2 + (r^2+a^2)^2*(Delta_th + sig*b^2*sinth2) ) \n",
"G[3,3] = tmp.simplify_full()\n",
"tmp = a*b*sinth2*mu^2/(rho2*Xi_a*Xi_b)*( - Delta_r + sig*(r^2+a^2)*(r^2+b^2) )\n",
"G[3,4] = tmp.simplify_full()\n",
"tmp = mu^2/(rho2*Xi_b^2)*( - Delta_r*b^2*mu^2 + (r^2+b^2)^2*(Delta_th + sig*a^2*mu^2) )\n",
"G[4,4] = tmp.simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 13,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\begin{array}{lcl} G_{ \\, t \\, t }^{ \\phantom{\\, t}\\phantom{\\, t} } & = & \\frac{a^{4} n^{2} - {\\left({\\Delta_\\theta} a^{2} {\\mu}^{2} - {\\Delta_\\theta} a^{2} - {\\left(a^{4} {\\ell}^{2} + {\\Delta_\\theta} a^{2} {\\mu}^{2}\\right)} n^{2} + {\\Delta_r}\\right)} r^{2}}{r^{4} + {\\left(a^{2} {\\mu}^{2} - {\\left(a^{2} {\\mu}^{2} - a^{2}\\right)} n^{2}\\right)} r^{2}} \\\\ G_{ \\, t \\, {\\phi} }^{ \\phantom{\\, t}\\phantom{\\, {\\phi}} } & = & \\frac{{\\left({\\Delta_\\theta} a {\\mu}^{2} + {\\left(a^{3} {\\ell}^{2} {\\mu}^{2} - a^{3} {\\ell}^{2}\\right)} n^{2} - {\\Delta_\\theta} a\\right)} r^{4} + {\\left(a^{5} {\\mu}^{2} - a^{5}\\right)} n^{2} - {\\left({\\Delta_\\theta} a^{3} - {\\left({\\Delta_\\theta} a^{3} - {\\Delta_r} a\\right)} {\\mu}^{2} + {\\left(a^{5} {\\ell}^{2} + a^{3} - {\\left(a^{5} {\\ell}^{2} + a^{3}\\right)} {\\mu}^{2}\\right)} n^{2} - {\\Delta_r} a\\right)} r^{2}}{{\\Xi_a} r^{4} + {\\left({\\Xi_a} a^{2} {\\mu}^{2} - {\\left({\\Xi_a} a^{2} {\\mu}^{2} - {\\Xi_a} a^{2}\\right)} n^{2}\\right)} r^{2}} \\\\ G_{ \\, t \\, {\\psi} }^{ \\phantom{\\, t}\\phantom{\\, {\\psi}} } & = & -\\frac{a^{5} {\\mu}^{2} n^{3} + {\\left(a^{3} {\\ell}^{2} + {\\Delta_\\theta} a\\right)} {\\mu}^{2} n r^{4} + {\\left({\\left(a^{5} {\\ell}^{2} + {\\Delta_\\theta} a^{3}\\right)} {\\mu}^{2} n^{3} + {\\left(a^{3} - {\\Delta_r} a\\right)} {\\mu}^{2} n\\right)} r^{2}}{{\\Xi_b} r^{4} + {\\left({\\Xi_b} a^{2} {\\mu}^{2} - {\\left({\\Xi_b} a^{2} {\\mu}^{2} - {\\Xi_b} a^{2}\\right)} n^{2}\\right)} r^{2}} \\\\ G_{ \\, r \\, r }^{ \\phantom{\\, r}\\phantom{\\, r} } & = & \\frac{a^{2} {\\mu}^{2} - {\\left(a^{2} {\\mu}^{2} - a^{2}\\right)} n^{2} + r^{2}}{{\\Delta_r}} \\\\ G_{ \\, {\\mu} \\, {\\mu} }^{ \\phantom{\\, {\\mu}}\\phantom{\\, {\\mu}} } & = & -\\frac{a^{2} {\\mu}^{2} - {\\left(a^{2} {\\mu}^{2} - a^{2}\\right)} n^{2} + r^{2}}{{\\Delta_\\theta} {\\mu}^{2} - {\\Delta_\\theta}} \\\\ G_{ \\, {\\phi} \\, {\\phi} }^{ \\phantom{\\, {\\phi}}\\phantom{\\, {\\phi}} } & = & -\\frac{{\\left({\\Delta_\\theta} {\\mu}^{2} - {\\left(a^{2} {\\ell}^{2} {\\mu}^{4} - 2 \\, a^{2} {\\ell}^{2} {\\mu}^{2} + a^{2} {\\ell}^{2}\\right)} n^{2} - {\\Delta_\\theta}\\right)} r^{6} + {\\left(2 \\, {\\Delta_\\theta} a^{2} {\\mu}^{2} - 2 \\, {\\Delta_\\theta} a^{2} - {\\left(2 \\, a^{4} {\\ell}^{2} + {\\left(2 \\, a^{4} {\\ell}^{2} + a^{2}\\right)} {\\mu}^{4} - 2 \\, {\\left(2 \\, a^{4} {\\ell}^{2} + a^{2}\\right)} {\\mu}^{2} + a^{2}\\right)} n^{2}\\right)} r^{4} - {\\left(a^{6} {\\mu}^{4} - 2 \\, a^{6} {\\mu}^{2} + a^{6}\\right)} n^{2} + {\\left({\\Delta_r} a^{2} {\\mu}^{4} - {\\Delta_\\theta} a^{4} + {\\Delta_r} a^{2} + {\\left({\\Delta_\\theta} a^{4} - 2 \\, {\\Delta_r} a^{2}\\right)} {\\mu}^{2} - {\\left(a^{6} {\\ell}^{2} + {\\left(a^{6} {\\ell}^{2} + 2 \\, a^{4}\\right)} {\\mu}^{4} + 2 \\, a^{4} - 2 \\, {\\left(a^{6} {\\ell}^{2} + 2 \\, a^{4}\\right)} {\\mu}^{2}\\right)} n^{2}\\right)} r^{2}}{{\\Xi_a}^{2} r^{4} + {\\left({\\Xi_a}^{2} a^{2} {\\mu}^{2} - {\\left({\\Xi_a}^{2} a^{2} {\\mu}^{2} - {\\Xi_a}^{2} a^{2}\\right)} n^{2}\\right)} r^{2}} \\\\ G_{ \\, {\\phi} \\, {\\psi} }^{ \\phantom{\\, {\\phi}}\\phantom{\\, {\\psi}} } & = & -\\frac{{\\left(a^{2} {\\ell}^{2} {\\mu}^{4} - a^{2} {\\ell}^{2} {\\mu}^{2}\\right)} n r^{6} + {\\left({\\left(a^{4} {\\ell}^{2} {\\mu}^{4} - a^{4} {\\ell}^{2} {\\mu}^{2}\\right)} n^{3} + {\\left({\\left(a^{4} {\\ell}^{2} + a^{2}\\right)} {\\mu}^{4} - {\\left(a^{4} {\\ell}^{2} + a^{2}\\right)} {\\mu}^{2}\\right)} n\\right)} r^{4} + {\\left(a^{6} {\\mu}^{4} - a^{6} {\\mu}^{2}\\right)} n^{3} + {\\left({\\left({\\left(a^{6} {\\ell}^{2} + a^{4}\\right)} {\\mu}^{4} - {\\left(a^{6} {\\ell}^{2} + a^{4}\\right)} {\\mu}^{2}\\right)} n^{3} + {\\left({\\left(a^{4} - {\\Delta_r} a^{2}\\right)} {\\mu}^{4} - {\\left(a^{4} - {\\Delta_r} a^{2}\\right)} {\\mu}^{2}\\right)} n\\right)} r^{2}}{{\\Xi_a} {\\Xi_b} r^{4} + {\\left({\\Xi_a} {\\Xi_b} a^{2} {\\mu}^{2} - {\\left({\\Xi_a} {\\Xi_b} a^{2} {\\mu}^{2} - {\\Xi_a} {\\Xi_b} a^{2}\\right)} n^{2}\\right)} r^{2}} \\\\ G_{ \\, {\\psi} \\, {\\psi} }^{ \\phantom{\\, {\\psi}}\\phantom{\\, {\\psi}} } & = & \\frac{a^{6} {\\mu}^{4} n^{4} + {\\left(a^{2} {\\ell}^{2} {\\mu}^{4} + {\\Delta_\\theta} {\\mu}^{2}\\right)} r^{6} + {\\left(a^{2} {\\mu}^{4} + 2 \\, {\\left(a^{4} {\\ell}^{2} {\\mu}^{4} + {\\Delta_\\theta} a^{2} {\\mu}^{2}\\right)} n^{2}\\right)} r^{4} + {\\left({\\left(2 \\, a^{4} - {\\Delta_r} a^{2}\\right)} {\\mu}^{4} n^{2} + {\\left(a^{6} {\\ell}^{2} {\\mu}^{4} + {\\Delta_\\theta} a^{4} {\\mu}^{2}\\right)} n^{4}\\right)} r^{2}}{{\\Xi_b}^{2} r^{4} + {\\left({\\Xi_b}^{2} a^{2} {\\mu}^{2} - {\\left({\\Xi_b}^{2} a^{2} {\\mu}^{2} - {\\Xi_b}^{2} a^{2}\\right)} n^{2}\\right)} r^{2}} \\end{array}$$"
],
"text/plain": [
"G_t,t = (a^4*n^2 - (Delta_th*a^2*mu^2 - Delta_th*a^2 - (a^4*l^2 + Delta_th*a^2*mu^2)*n^2 + Delta_r)*r^2)/(r^4 + (a^2*mu^2 - (a^2*mu^2 - a^2)*n^2)*r^2) \n",
"G_t,ph = ((Delta_th*a*mu^2 + (a^3*l^2*mu^2 - a^3*l^2)*n^2 - Delta_th*a)*r^4 + (a^5*mu^2 - a^5)*n^2 - (Delta_th*a^3 - (Delta_th*a^3 - Delta_r*a)*mu^2 + (a^5*l^2 + a^3 - (a^5*l^2 + a^3)*mu^2)*n^2 - Delta_r*a)*r^2)/(Xi_a*r^4 + (Xi_a*a^2*mu^2 - (Xi_a*a^2*mu^2 - Xi_a*a^2)*n^2)*r^2) \n",
"G_t,ps = -(a^5*mu^2*n^3 + (a^3*l^2 + Delta_th*a)*mu^2*n*r^4 + ((a^5*l^2 + Delta_th*a^3)*mu^2*n^3 + (a^3 - Delta_r*a)*mu^2*n)*r^2)/(Xi_b*r^4 + (Xi_b*a^2*mu^2 - (Xi_b*a^2*mu^2 - Xi_b*a^2)*n^2)*r^2) \n",
"G_r,r = (a^2*mu^2 - (a^2*mu^2 - a^2)*n^2 + r^2)/Delta_r \n",
"G_mu,mu = -(a^2*mu^2 - (a^2*mu^2 - a^2)*n^2 + r^2)/(Delta_th*mu^2 - Delta_th) \n",
"G_ph,ph = -((Delta_th*mu^2 - (a^2*l^2*mu^4 - 2*a^2*l^2*mu^2 + a^2*l^2)*n^2 - Delta_th)*r^6 + (2*Delta_th*a^2*mu^2 - 2*Delta_th*a^2 - (2*a^4*l^2 + (2*a^4*l^2 + a^2)*mu^4 - 2*(2*a^4*l^2 + a^2)*mu^2 + a^2)*n^2)*r^4 - (a^6*mu^4 - 2*a^6*mu^2 + a^6)*n^2 + (Delta_r*a^2*mu^4 - Delta_th*a^4 + Delta_r*a^2 + (Delta_th*a^4 - 2*Delta_r*a^2)*mu^2 - (a^6*l^2 + (a^6*l^2 + 2*a^4)*mu^4 + 2*a^4 - 2*(a^6*l^2 + 2*a^4)*mu^2)*n^2)*r^2)/(Xi_a^2*r^4 + (Xi_a^2*a^2*mu^2 - (Xi_a^2*a^2*mu^2 - Xi_a^2*a^2)*n^2)*r^2) \n",
"G_ph,ps = -((a^2*l^2*mu^4 - a^2*l^2*mu^2)*n*r^6 + ((a^4*l^2*mu^4 - a^4*l^2*mu^2)*n^3 + ((a^4*l^2 + a^2)*mu^4 - (a^4*l^2 + a^2)*mu^2)*n)*r^4 + (a^6*mu^4 - a^6*mu^2)*n^3 + (((a^6*l^2 + a^4)*mu^4 - (a^6*l^2 + a^4)*mu^2)*n^3 + ((a^4 - Delta_r*a^2)*mu^4 - (a^4 - Delta_r*a^2)*mu^2)*n)*r^2)/(Xi_a*Xi_b*r^4 + (Xi_a*Xi_b*a^2*mu^2 - (Xi_a*Xi_b*a^2*mu^2 - Xi_a*Xi_b*a^2)*n^2)*r^2) \n",
"G_ps,ps = (a^6*mu^4*n^4 + (a^2*l^2*mu^4 + Delta_th*mu^2)*r^6 + (a^2*mu^4 + 2*(a^4*l^2*mu^4 + Delta_th*a^2*mu^2)*n^2)*r^4 + ((2*a^4 - Delta_r*a^2)*mu^4*n^2 + (a^6*l^2*mu^4 + Delta_th*a^4*mu^2)*n^4)*r^2)/(Xi_b^2*r^4 + (Xi_b^2*a^2*mu^2 - (Xi_b^2*a^2*mu^2 - Xi_b^2*a^2)*n^2)*r^2) "
]
},
"execution_count": 13,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"G.display_comp(only_nonredundant=True)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Check of Eq. (2.9)\n",
"\n",
"We need the 1-forms $\\mathrm{d}t$, $\\mathrm{d}r$, $\\mathrm{d}\\mu$, $\\mathrm{d}\\phi$ and $\\mathrm{d}\\psi$:"
]
},
{
"cell_type": "code",
"execution_count": 14,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left(\\mathrm{d} t, \\mathrm{d} r, \\mathrm{d} {\\mu}, \\mathrm{d} {\\phi}, \\mathrm{d} {\\psi}\\right)$$"
],
"text/plain": [
"(1-form dt on the 5-dimensional Lorentzian manifold M,\n",
" 1-form dr on the 5-dimensional Lorentzian manifold M,\n",
" 1-form dmu on the 5-dimensional Lorentzian manifold M,\n",
" 1-form dph on the 5-dimensional Lorentzian manifold M,\n",
" 1-form dps on the 5-dimensional Lorentzian manifold M)"
]
},
"execution_count": 14,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"dt, dr, dmu, dph, dps = (BL.coframe()[i] for i in M.irange())\n",
"dt, dr, dmu, dph, dps"
]
},
{
"cell_type": "code",
"execution_count": 15,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1-form dt on the 5-dimensional Lorentzian manifold M\n"
]
}
],
"source": [
"print(dt)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"In agreement with $\\mu = \\cos\\theta$, we introduce the 1-form\n",
"$$\\mathrm{d}\\theta = - \\mathrm{d}\\mu /\\sin\\theta ,$$\n",
"with\n",
"$\\sin\\theta = \\sqrt{1-\\mu^2}$ since $\\theta\\in\\left(0, \\frac{\\pi}{2}\\right)$ :"
]
},
{
"cell_type": "code",
"execution_count": 16,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"dth = - 1/sqrt(1 - mu^2)*dmu"
]
},
{
"cell_type": "code",
"execution_count": 17,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\mathrm{d} t + \\left( \\frac{a {\\mu}^{2} - a}{{\\Xi_a}} \\right) \\mathrm{d} {\\phi} -\\frac{a {\\mu}^{2} n}{{\\Xi_b}} \\mathrm{d} {\\psi}$$"
],
"text/plain": [
"dt + (a*mu^2 - a)/Xi_a dph - a*mu^2*n/Xi_b dps"
]
},
"execution_count": 17,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s1 = dt - a*sinth2/Xi_a*dph - b*costh2/Xi_b*dps\n",
"s1.display()"
]
},
{
"cell_type": "code",
"execution_count": 18,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}a \\mathrm{d} t + \\left( -\\frac{a^{2} + r^{2}}{{\\Xi_a}} \\right) \\mathrm{d} {\\phi}$$"
],
"text/plain": [
"a dt - (a^2 + r^2)/Xi_a dph"
]
},
"execution_count": 18,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2 = a*dt - (r^2 + a^2)/Xi_a*dph\n",
"s2.display()"
]
},
{
"cell_type": "code",
"execution_count": 19,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}a n \\mathrm{d} t + \\left( -\\frac{a^{2} n^{2} + r^{2}}{{\\Xi_b}} \\right) \\mathrm{d} {\\psi}$$"
],
"text/plain": [
"a*n dt - (a^2*n^2 + r^2)/Xi_b dps"
]
},
"execution_count": 19,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s3 = b*dt - (r^2 + b^2)/Xi_b*dps\n",
"s3.display()"
]
},
{
"cell_type": "code",
"execution_count": 20,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}a^{2} n \\mathrm{d} t + \\left( \\frac{{\\left(a {\\mu}^{2} - a\\right)} n r^{2} + {\\left(a^{3} {\\mu}^{2} - a^{3}\\right)} n}{{\\Xi_a}} \\right) \\mathrm{d} {\\phi} + \\left( -\\frac{a^{3} {\\mu}^{2} n^{2} + a {\\mu}^{2} r^{2}}{{\\Xi_b}} \\right) \\mathrm{d} {\\psi}$$"
],
"text/plain": [
"a^2*n dt + ((a*mu^2 - a)*n*r^2 + (a^3*mu^2 - a^3)*n)/Xi_a dph - (a^3*mu^2*n^2 + a*mu^2*r^2)/Xi_b dps"
]
},
"execution_count": 20,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s4 = a*b*dt - b*(r^2 + a^2)*sinth2/Xi_a * dph - a*(r^2 + b^2)*costh2/Xi_b * dps\n",
"s4.display()"
]
},
{
"cell_type": "code",
"execution_count": 21,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"G0 = - Delta_r/rho2 * s1*s1 + Delta_th*sinth2/rho2 * s2*s2 \\\n",
" + Delta_th*costh2/rho2 * s3*s3 + rho2/Delta_r * dr*dr \\\n",
" + rho2/Delta_th * dth*dth + sig/rho2 * s4*s4"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Check of Eq. (2.9):"
]
},
{
"cell_type": "code",
"execution_count": 22,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\mathrm{True}$$"
],
"text/plain": [
"True"
]
},
"execution_count": 22,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"G0 == G"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"## Einstein equation\n",
"\n",
"The Ricci tensor of $g$ is"
]
},
{
"cell_type": "code",
"execution_count": 23,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"if not keep_Delta:\n",
" # Ric = G.ricci()\n",
" # print(Ric)\n",
" pass"
]
},
{
"cell_type": "code",
"execution_count": 24,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"if not keep_Delta:\n",
" # show(Ric.display_comp(only_nonredundant=True))\n",
" pass"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"Let us check that $g$ is a solution of the vacuum Einstein equation with the cosmological constant $\\Lambda = - 6 \\ell^2$:"
]
},
{
"cell_type": "code",
"execution_count": 25,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"Lambda = -6*l^2\n",
"if not keep_Delta:\n",
" # print(Ric == 2/3*Lambda*G)\n",
" pass"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"## String worldsheet"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"The string worldsheet as a 2-dimensional Lorentzian submanifold of $\\mathcal{M}$:"
]
},
{
"cell_type": "code",
"execution_count": 26,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"2-dimensional Lorentzian submanifold W immersed in the 5-dimensional Lorentzian manifold M\n"
]
}
],
"source": [
"W = Manifold(2, 'W', ambient=M, structure='Lorentzian', \n",
" latex_name=r'\\mathcal{W}')\n",
"print(W)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"Let us assume that the string worldsheet is parametrized by $(t,r)$:"
]
},
{
"cell_type": "code",
"execution_count": 27,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left(\\mathcal{W},(t, r)\\right)$$"
],
"text/plain": [
"Chart (W, (t, r))"
]
},
"execution_count": 27,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"XW. = W.chart(r't r:(0,+oo)')\n",
"XW"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"The string embedding in Kerr-AdS spacetime, as an expansion about a \n",
"straight string solution in AdS (Eq. (4.5) of the paper):"
]
},
{
"cell_type": "code",
"execution_count": 28,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\begin{array}{llcl} F:& \\mathcal{W} & \\longrightarrow & \\mathcal{M} \\\\ & \\left(t, r\\right) & \\longmapsto & \\left(t, r, {\\mu}, {\\phi}, {\\psi}\\right) = \\left(t, r, {\\left(a n + a\\right)}^{2} \\mu_{1}\\left(r\\right) + {\\mu_0}, a {\\ell}^{2} t + a \\phi_{1}\\left(r\\right) + {\\Phi_0}, a {\\ell}^{2} n t + a n \\psi_{1}\\left(r\\right) + {\\Psi_0}\\right) \\end{array}$$"
],
"text/plain": [
"F: W --> M\n",
" (t, r) |--> (t, r, mu, ph, ps) = (t, r, (a*n + a)^2*mu_1(r) + Mu0, a*l^2*t + a*phi_1(r) + Phi0, a*l^2*n*t + a*n*psi_1(r) + Psi0)"
]
},
"execution_count": 28,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Mu0 = var('Mu0', latex_name=r'\\mu_0', domain='real')\n",
"Phi0 = var('Phi0', latex_name=r'\\Phi_0', domain='real')\n",
"Psi0 = var('Psi0', latex_name=r'\\Psi_0', domain='real')\n",
"\n",
"cosTh0 = Mu0\n",
"sinTh0 = sqrt(1 - Mu0^2)\n",
"\n",
"mu_s = Mu0 + (a+b)^2*function('mu_1')(r)\n",
"ph_s = Phi0 + a*l^2*t + a*function('phi_1')(r)\n",
"ps_s = Psi0 + b*l^2*t + b*function('psi_1')(r)\n",
"\n",
"F = W.diff_map(M, {(XW, BL): [t, r, mu_s, ph_s, ps_s]}, name='F') \n",
"\n",
"W.set_embedding(F)\n",
"\n",
"F.display()"
]
},
{
"cell_type": "code",
"execution_count": 29,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left(\\begin{array}{rr}\n",
"1 & 0 \\\\\n",
"0 & 1 \\\\\n",
"0 & {\\left(a^{2} n^{2} + 2 \\, a^{2} n + a^{2}\\right)} \\frac{\\partial}{\\partial r}\\mu_{1}\\left(r\\right) \\\\\n",
"a {\\ell}^{2} & a \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right) \\\\\n",
"a {\\ell}^{2} n & a n \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)\n",
"\\end{array}\\right)$$"
],
"text/plain": [
"[ 1 0]\n",
"[ 0 1]\n",
"[ 0 (a^2*n^2 + 2*a^2*n + a^2)*diff(mu_1(r), r)]\n",
"[ a*l^2 a*diff(phi_1(r), r)]\n",
"[ a*l^2*n a*n*diff(psi_1(r), r)]"
]
},
"execution_count": 29,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"F.jacobian_matrix()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false,
"size": 4
},
"source": [
"### Induced metric on the string worldsheet"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Because of the bug [#27492](https://trac.sagemath.org/ticket/27492), which impedes parallel computations involving symbolic functions, such as $\\mu_1$, we switch back to serial computations:"
]
},
{
"cell_type": "code",
"execution_count": 30,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"Parallelism().set(nproc=1)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The metric on the string worldsheet $\\mathcal{W}$ is the metric $g$ induced by the spacetime metric $G$, i.e. the pullback of $G$ by the embedding $F$:"
]
},
{
"cell_type": "code",
"execution_count": 31,
"metadata": {
"collapsed": false,
"size": 4
},
"outputs": [
],
"source": [
"g = W.induced_metric()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"## Nambu-Goto action"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The determinant of $g$ is"
]
},
{
"cell_type": "code",
"execution_count": 32,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"detg = g.determinant().expr()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Expanding at fourth order in $a$ (will be required latter):"
]
},
{
"cell_type": "code",
"execution_count": 33,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"detg_a4 = detg.series(a, 5).truncate().simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 34,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"detg_a40 = detg_a4"
]
},
{
"cell_type": "code",
"execution_count": 35,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"detg_a4 = detg_a40"
]
},
{
"cell_type": "code",
"execution_count": 36,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"detg_a4 = detg_a4.subs({Xi_a: Xi_a_expr, Xi_b: Xi_b_expr, \n",
" Delta_r: Delta_r_expr, Delta_th: Delta_th_expr})\n",
"detg_a4 = detg_a4.subs({mu: mu_s})"
]
},
{
"cell_type": "code",
"execution_count": 37,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"detg_a4 = detg_a4.series(a, 5).truncate().simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 38,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left({\\mu_0}, a, {\\ell}, m, n, r\\right)$$"
],
"text/plain": [
"(Mu0, a, l, m, n, r)"
]
},
"execution_count": 38,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"detg_a4.variables()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"For the time being, only the expansion at second order in $a$ is required:"
]
},
{
"cell_type": "code",
"execution_count": 39,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"detg_a2 = detg_a4.series(a, 3).truncate().simplify_full()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The Nambu-Goto Lagrangian at second order in $a$:"
]
},
{
"cell_type": "code",
"execution_count": 40,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{{\\left(3 \\, {\\mu_0}^{2} a^{2} {\\ell}^{4} n^{2} - 3 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{4} - 2 \\, {\\ell}^{2}\\right)} r^{4} - {\\left({\\mu_0}^{2} - 1\\right)} a^{2} - {\\left(4 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} m - {\\mu_0}^{2} a^{2}\\right)} n^{2} + {\\left({\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{4} r^{8} + 2 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} r^{6} - 4 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} m r^{2} + 4 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} m^{2} - {\\left(4 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} m - {\\left({\\mu_0}^{2} - 1\\right)} a^{2}\\right)} r^{4}\\right)} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} - {\\left({\\mu_0}^{2} a^{2} {\\ell}^{4} n^{2} r^{8} + 2 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} n^{2} r^{6} - 4 \\, {\\mu_0}^{2} a^{2} m n^{2} r^{2} + 4 \\, {\\mu_0}^{2} a^{2} m^{2} n^{2} - {\\left(4 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} m - {\\mu_0}^{2} a^{2}\\right)} n^{2} r^{4}\\right)} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} + 4 \\, {\\left({\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} + 1\\right)} m - 2 \\, r^{2}}{2 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)}}$$"
],
"text/plain": [
"-1/2*((3*Mu0^2*a^2*l^4*n^2 - 3*(Mu0^2 - 1)*a^2*l^4 - 2*l^2)*r^4 - (Mu0^2 - 1)*a^2 - (4*Mu0^2*a^2*l^2*m - Mu0^2*a^2)*n^2 + ((Mu0^2 - 1)*a^2*l^4*r^8 + 2*(Mu0^2 - 1)*a^2*l^2*r^6 - 4*(Mu0^2 - 1)*a^2*m*r^2 + 4*(Mu0^2 - 1)*a^2*m^2 - (4*(Mu0^2 - 1)*a^2*l^2*m - (Mu0^2 - 1)*a^2)*r^4)*diff(phi_1(r), r)^2 - (Mu0^2*a^2*l^4*n^2*r^8 + 2*Mu0^2*a^2*l^2*n^2*r^6 - 4*Mu0^2*a^2*m*n^2*r^2 + 4*Mu0^2*a^2*m^2*n^2 - (4*Mu0^2*a^2*l^2*m - Mu0^2*a^2)*n^2*r^4)*diff(psi_1(r), r)^2 + 4*((Mu0^2 - 1)*a^2*l^2 + 1)*m - 2*r^2)/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 40,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"L_a2 = (sqrt(-detg_a2)).series(a, 3).truncate().simplify_full()\n",
"L_a2"
]
},
{
"cell_type": "code",
"execution_count": 41,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\mu_0}^{2} a^{2} {\\ell}^{4} n^{2} r^{8} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} - {\\mu_0}^{2} a^{2} {\\ell}^{4} r^{8} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + a^{2} {\\ell}^{4} r^{8} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + 2 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} n^{2} r^{6} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} - 4 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} m n^{2} r^{4} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} - 3 \\, {\\mu_0}^{2} a^{2} {\\ell}^{4} n^{2} r^{4} - 2 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} r^{6} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + 4 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} m r^{4} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + 3 \\, {\\mu_0}^{2} a^{2} {\\ell}^{4} r^{4} + 2 \\, a^{2} {\\ell}^{2} r^{6} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + {\\mu_0}^{2} a^{2} n^{2} r^{4} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} - 4 \\, a^{2} {\\ell}^{2} m r^{4} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} - 4 \\, {\\mu_0}^{2} a^{2} m n^{2} r^{2} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} - 3 \\, a^{2} {\\ell}^{4} r^{4} - {\\mu_0}^{2} a^{2} r^{4} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + 4 \\, {\\mu_0}^{2} a^{2} m^{2} n^{2} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} + 4 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} m n^{2} + 4 \\, {\\mu_0}^{2} a^{2} m r^{2} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} - 4 \\, {\\mu_0}^{2} a^{2} m^{2} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + a^{2} r^{4} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} - 4 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} m - 4 \\, a^{2} m r^{2} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} - {\\mu_0}^{2} a^{2} n^{2} + 2 \\, {\\ell}^{2} r^{4} + 4 \\, a^{2} m^{2} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + 4 \\, a^{2} {\\ell}^{2} m + {\\mu_0}^{2} a^{2} - a^{2} + 2 \\, r^{2} - 4 \\, m$$"
],
"text/plain": [
"Mu0^2*a^2*l^4*n^2*r^8*diff(psi_1(r), r)^2 - Mu0^2*a^2*l^4*r^8*diff(phi_1(r), r)^2 + a^2*l^4*r^8*diff(phi_1(r), r)^2 + 2*Mu0^2*a^2*l^2*n^2*r^6*diff(psi_1(r), r)^2 - 4*Mu0^2*a^2*l^2*m*n^2*r^4*diff(psi_1(r), r)^2 - 3*Mu0^2*a^2*l^4*n^2*r^4 - 2*Mu0^2*a^2*l^2*r^6*diff(phi_1(r), r)^2 + 4*Mu0^2*a^2*l^2*m*r^4*diff(phi_1(r), r)^2 + 3*Mu0^2*a^2*l^4*r^4 + 2*a^2*l^2*r^6*diff(phi_1(r), r)^2 + Mu0^2*a^2*n^2*r^4*diff(psi_1(r), r)^2 - 4*a^2*l^2*m*r^4*diff(phi_1(r), r)^2 - 4*Mu0^2*a^2*m*n^2*r^2*diff(psi_1(r), r)^2 - 3*a^2*l^4*r^4 - Mu0^2*a^2*r^4*diff(phi_1(r), r)^2 + 4*Mu0^2*a^2*m^2*n^2*diff(psi_1(r), r)^2 + 4*Mu0^2*a^2*l^2*m*n^2 + 4*Mu0^2*a^2*m*r^2*diff(phi_1(r), r)^2 - 4*Mu0^2*a^2*m^2*diff(phi_1(r), r)^2 + a^2*r^4*diff(phi_1(r), r)^2 - 4*Mu0^2*a^2*l^2*m - 4*a^2*m*r^2*diff(phi_1(r), r)^2 - Mu0^2*a^2*n^2 + 2*l^2*r^4 + 4*a^2*m^2*diff(phi_1(r), r)^2 + 4*a^2*l^2*m + Mu0^2*a^2 - a^2 + 2*r^2 - 4*m"
]
},
"execution_count": 41,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"L_a2.numerator()"
]
},
{
"cell_type": "code",
"execution_count": 42,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}2 \\, {\\ell}^{2} r^{4} + 2 \\, r^{2} - 4 \\, m$$"
],
"text/plain": [
"2*l^2*r^4 + 2*r^2 - 4*m"
]
},
"execution_count": 42,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"L_a2.denominator()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Euler-Lagrange equations"
]
},
{
"cell_type": "code",
"execution_count": 43,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"def euler_lagrange(lagr, qs, var):\n",
" r\"\"\"\n",
" Derive the Euler-Lagrange equations from a given Lagrangian.\n",
"\n",
" INPUT:\n",
"\n",
" - ``lagr`` -- symbolic expression representing the Lagrangian density\n",
" - ``qs`` -- either a single symbolic function or a list/tuple of\n",
" symbolic functions, representing the `q`'s; these functions must\n",
" appear in ``lagr`` up to at most their first derivatives\n",
" - ``var`` -- either a single variable, typically `t` (1-dimensional\n",
" problem) or a list/tuple of symbolic variables\n",
"\n",
" OUTPUT:\n",
"\n",
" - list of Euler-Lagrange equations; if only one function is involved, the\n",
" single Euler-Lagrannge equation is returned instead.\n",
"\n",
" \"\"\"\n",
" if not isinstance(qs, (list, tuple)):\n",
" qs = [qs]\n",
" if not isinstance(var, (list, tuple)):\n",
" var = [var]\n",
" n = len(qs)\n",
" d = len(var)\n",
" qv = [SR.var('qxxxx{}'.format(q)) for q in qs]\n",
" dqv = [[SR.var('qxxxx{}_{}'.format(q, v)) for v in var] for q in qs]\n",
" subs = {qs[i](*var): qv[i] for i in range(n)}\n",
" subs_inv = {qv[i]: qs[i](*var) for i in range(n)}\n",
" for i in range(n):\n",
" subs.update({diff(qs[i](*var), var[j]): dqv[i][j]\n",
" for j in range(d)})\n",
" subs_inv.update({dqv[i][j]: diff(qs[i](*var), var[j])\n",
" for j in range(d)})\n",
" lg = lagr.substitute(subs)\n",
" eqs = []\n",
" for i in range(n):\n",
" dLdq = diff(lg, qv[i]).simplify_full()\n",
" dLdq = dLdq.substitute(subs_inv)\n",
" ddL = 0\n",
" for j in range(d):\n",
" h = diff(lg, dqv[i][j]).simplify_full()\n",
" h = h.substitute(subs_inv)\n",
" ddL += diff(h, var[j])\n",
" eqs.append((dLdq - ddL).simplify_full() == 0)\n",
" if n == 1:\n",
" return eqs[0]\n",
" return eqs"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We compute the Euler-Lagrange equations at order $a^2$ for $\\phi_1$ and $\\psi_1$:"
]
},
{
"cell_type": "code",
"execution_count": 44,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left[2 \\, {\\left(2 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} r^{3} + {\\left({\\mu_0}^{2} - 1\\right)} a^{2} r\\right)} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right) + {\\left({\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} r^{4} + {\\left({\\mu_0}^{2} - 1\\right)} a^{2} r^{2} - 2 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} m\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\phi_{1}\\left(r\\right) = 0, -2 \\, {\\left(2 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} n^{2} r^{3} + {\\mu_0}^{2} a^{2} n^{2} r\\right)} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right) - {\\left({\\mu_0}^{2} a^{2} {\\ell}^{2} n^{2} r^{4} + {\\mu_0}^{2} a^{2} n^{2} r^{2} - 2 \\, {\\mu_0}^{2} a^{2} m n^{2}\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\psi_{1}\\left(r\\right) = 0\\right]$$"
],
"text/plain": [
"[2*(2*(Mu0^2 - 1)*a^2*l^2*r^3 + (Mu0^2 - 1)*a^2*r)*diff(phi_1(r), r) + ((Mu0^2 - 1)*a^2*l^2*r^4 + (Mu0^2 - 1)*a^2*r^2 - 2*(Mu0^2 - 1)*a^2*m)*diff(phi_1(r), r, r) == 0,\n",
" -2*(2*Mu0^2*a^2*l^2*n^2*r^3 + Mu0^2*a^2*n^2*r)*diff(psi_1(r), r) - (Mu0^2*a^2*l^2*n^2*r^4 + Mu0^2*a^2*n^2*r^2 - 2*Mu0^2*a^2*m*n^2)*diff(psi_1(r), r, r) == 0]"
]
},
"execution_count": 44,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eqs = euler_lagrange(L_a2, [phi_1, psi_1], r)\n",
"eqs"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"#### Solving the equation for $\\phi_1$ (Eq. (4.8))"
]
},
{
"cell_type": "code",
"execution_count": 45,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}2 \\, {\\left(2 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} r^{3} + {\\left({\\mu_0}^{2} - 1\\right)} a^{2} r\\right)} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right) + {\\left({\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} r^{4} + {\\left({\\mu_0}^{2} - 1\\right)} a^{2} r^{2} - 2 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} m\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\phi_{1}\\left(r\\right) = 0$$"
],
"text/plain": [
"2*(2*(Mu0^2 - 1)*a^2*l^2*r^3 + (Mu0^2 - 1)*a^2*r)*diff(phi_1(r), r) + ((Mu0^2 - 1)*a^2*l^2*r^4 + (Mu0^2 - 1)*a^2*r^2 - 2*(Mu0^2 - 1)*a^2*m)*diff(phi_1(r), r, r) == 0"
]
},
"execution_count": 45,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_phi1 = eqs[0]\n",
"eq_phi1"
]
},
{
"cell_type": "code",
"execution_count": 46,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}2 \\, {\\left(2 \\, {\\ell}^{2} r^{3} + r\\right)} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right) + {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\phi_{1}\\left(r\\right) = 0$$"
],
"text/plain": [
"2*(2*l^2*r^3 + r)*diff(phi_1(r), r) + (l^2*r^4 + r^2 - 2*m)*diff(phi_1(r), r, r) == 0"
]
},
"execution_count": 46,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_phi1 = (eq_phi1/(a^2*(Mu0^2-1))).simplify_full()\n",
"eq_phi1"
]
},
{
"cell_type": "code",
"execution_count": 47,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}K_{1} \\int \\frac{1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}\\,{d r} + K_{2}$$"
],
"text/plain": [
"_K1*integrate(1/(l^2*r^4 + r^2 - 2*m), r) + _K2"
]
},
"execution_count": 47,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"phi1_sol(r) = desolve(eq_phi1, phi_1(r), ivar=r)\n",
"phi1_sol(r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We recover Eqs. (4.8) with $K_1 = \\mathfrak{p}$ and $K_2=0$."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The symbolic constants $K_1$ and $K_2$ are actually denoted `_K1` and `_K2` by SageMath, as the `print` reveals:"
]
},
{
"cell_type": "code",
"execution_count": 48,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"_K1*integrate(1/(l^2*r^4 + r^2 - 2*m), r) + _K2\n"
]
}
],
"source": [
"print(phi1_sol(r))"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Hence we perform the substitutions with `SR.var('_K1')` and `SR.var('_K2')`:"
]
},
{
"cell_type": "code",
"execution_count": 49,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\mathfrak{p}} \\int \\frac{1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}\\,{d r}$$"
],
"text/plain": [
"pf*integrate(1/(l^2*r^4 + r^2 - 2*m), r)"
]
},
"execution_count": 49,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"pf = var(\"pf\", latex_name=r\"\\mathfrak{p}\")\n",
"phi1_sol(r) = phi1_sol(r).subs({SR.var('_K1'): pf, SR.var('_K2'): 0})\n",
"phi1_sol(r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"#### Solving the equation for $\\psi_1$ (Eq. (4.8))"
]
},
{
"cell_type": "code",
"execution_count": 50,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-2 \\, {\\left(2 \\, {\\mu_0}^{2} a^{2} {\\ell}^{2} n^{2} r^{3} + {\\mu_0}^{2} a^{2} n^{2} r\\right)} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right) - {\\left({\\mu_0}^{2} a^{2} {\\ell}^{2} n^{2} r^{4} + {\\mu_0}^{2} a^{2} n^{2} r^{2} - 2 \\, {\\mu_0}^{2} a^{2} m n^{2}\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\psi_{1}\\left(r\\right) = 0$$"
],
"text/plain": [
"-2*(2*Mu0^2*a^2*l^2*n^2*r^3 + Mu0^2*a^2*n^2*r)*diff(psi_1(r), r) - (Mu0^2*a^2*l^2*n^2*r^4 + Mu0^2*a^2*n^2*r^2 - 2*Mu0^2*a^2*m*n^2)*diff(psi_1(r), r, r) == 0"
]
},
"execution_count": 50,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_psi1 = eqs[1]\n",
"eq_psi1"
]
},
{
"cell_type": "code",
"execution_count": 51,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-2 \\, {\\left(2 \\, {\\ell}^{2} n^{2} r^{3} + n^{2} r\\right)} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right) - {\\left({\\ell}^{2} n^{2} r^{4} + n^{2} r^{2} - 2 \\, m n^{2}\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\psi_{1}\\left(r\\right) = 0$$"
],
"text/plain": [
"-2*(2*l^2*n^2*r^3 + n^2*r)*diff(psi_1(r), r) - (l^2*n^2*r^4 + n^2*r^2 - 2*m*n^2)*diff(psi_1(r), r, r) == 0"
]
},
"execution_count": 51,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_psi1 = (eq_psi1/(a^2*Mu0^2)).simplify_full()\n",
"eq_psi1"
]
},
{
"cell_type": "code",
"execution_count": 52,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}K_{1} \\int \\frac{1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}\\,{d r} + K_{2}$$"
],
"text/plain": [
"_K1*integrate(1/(l^2*r^4 + r^2 - 2*m), r) + _K2"
]
},
"execution_count": 52,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"psi1_sol(r) = desolve(eq_psi1, psi_1(r), ivar=r)\n",
"psi1_sol(r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We recover Eq. (4.8) with $K_1 = \\mathfrak{q}$ and $K_2=0$."
]
},
{
"cell_type": "code",
"execution_count": 53,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\mathfrak{q}} \\int \\frac{1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}\\,{d r}$$"
],
"text/plain": [
"qf*integrate(1/(l^2*r^4 + r^2 - 2*m), r)"
]
},
"execution_count": 53,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"qf = var('qf', latex_name=r\"\\mathfrak{q}\")\n",
"psi1_sol(r) = psi1_sol(r).subs({SR.var('_K1'): qf, SR.var('_K2'): 0})\n",
"psi1_sol(r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Nambu-Goto Lagrangian at fourth order in $a$"
]
},
{
"cell_type": "code",
"execution_count": 54,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"L_a4 = (sqrt(-detg_a4)).series(a, 5).truncate().simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 55,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"eqs = euler_lagrange(L_a4, [phi_1, psi_1, mu_1], r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### The equation for $\\mu_1$"
]
},
{
"cell_type": "code",
"execution_count": 56,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} - {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n^{4} + 3 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n^{3} - 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4}\\right)} r^{4} - 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n^{3} + {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m^{2} n^{2} + {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4}\\right)} r^{8} + 8 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m^{2} n + 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m^{2} + 2 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} n + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2}\\right)} r^{6} - {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} + {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n^{2} + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n\\right)} r^{4} - 4 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m n + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m\\right)} r^{2}\\right)} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} - {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m^{2} n^{4} + 8 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m^{2} n^{3} + 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m^{2} n^{2} + {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{4} n^{2}\\right)} r^{8} + 2 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} n^{2}\\right)} r^{6} - {\\left({\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n^{4} + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n^{3} + {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n^{2}\\right)} r^{4} - 4 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} m n^{2}\\right)} r^{2}\\right)} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4} {\\ell}^{2} m - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} a^{4}\\right)} n - 2 \\, {\\left(2 \\, {\\left(a^{4} {\\ell}^{4} n^{4} + 4 \\, a^{4} {\\ell}^{4} n^{3} + 6 \\, a^{4} {\\ell}^{4} n^{2} + 4 \\, a^{4} {\\ell}^{4} n + a^{4} {\\ell}^{4}\\right)} r^{7} + 3 \\, {\\left(a^{4} {\\ell}^{2} n^{4} + 4 \\, a^{4} {\\ell}^{2} n^{3} + 6 \\, a^{4} {\\ell}^{2} n^{2} + 4 \\, a^{4} {\\ell}^{2} n + a^{4} {\\ell}^{2}\\right)} r^{5} - {\\left(4 \\, a^{4} {\\ell}^{2} m + {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n^{4} - a^{4} + 4 \\, {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n^{3} + 6 \\, {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n^{2} + 4 \\, {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n\\right)} r^{3} - 2 \\, {\\left(a^{4} m n^{4} + 4 \\, a^{4} m n^{3} + 6 \\, a^{4} m n^{2} + 4 \\, a^{4} m n + a^{4} m\\right)} r\\right)} \\frac{\\partial}{\\partial r}\\mu_{1}\\left(r\\right) - {\\left(4 \\, a^{4} m^{2} n^{4} + 16 \\, a^{4} m^{2} n^{3} + {\\left(a^{4} {\\ell}^{4} n^{4} + 4 \\, a^{4} {\\ell}^{4} n^{3} + 6 \\, a^{4} {\\ell}^{4} n^{2} + 4 \\, a^{4} {\\ell}^{4} n + a^{4} {\\ell}^{4}\\right)} r^{8} + 24 \\, a^{4} m^{2} n^{2} + 16 \\, a^{4} m^{2} n + 2 \\, {\\left(a^{4} {\\ell}^{2} n^{4} + 4 \\, a^{4} {\\ell}^{2} n^{3} + 6 \\, a^{4} {\\ell}^{2} n^{2} + 4 \\, a^{4} {\\ell}^{2} n + a^{4} {\\ell}^{2}\\right)} r^{6} + 4 \\, a^{4} m^{2} - {\\left(4 \\, a^{4} {\\ell}^{2} m + {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n^{4} - a^{4} + 4 \\, {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n^{3} + 6 \\, {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n^{2} + 4 \\, {\\left(4 \\, a^{4} {\\ell}^{2} m - a^{4}\\right)} n\\right)} r^{4} - 4 \\, {\\left(a^{4} m n^{4} + 4 \\, a^{4} m n^{3} + 6 \\, a^{4} m n^{2} + 4 \\, a^{4} m n + a^{4} m\\right)} r^{2}\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\mu_{1}\\left(r\\right)}{{\\left({\\mu_0}^{2} - 1\\right)} {\\ell}^{2} r^{4} + {\\left({\\mu_0}^{2} - 1\\right)} r^{2} - 2 \\, {\\left({\\mu_0}^{2} - 1\\right)} m} = 0$$"
],
"text/plain": [
"-(4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4 - (4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n^4 + 3*((Mu0^3 - Mu0)*a^4*l^4*n^4 + 2*(Mu0^3 - Mu0)*a^4*l^4*n^3 - 2*(Mu0^3 - Mu0)*a^4*l^4*n - (Mu0^3 - Mu0)*a^4*l^4)*r^4 - 2*(4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n^3 + (4*(Mu0^3 - Mu0)*a^4*m^2*n^2 + ((Mu0^3 - Mu0)*a^4*l^4*n^2 + 2*(Mu0^3 - Mu0)*a^4*l^4*n + (Mu0^3 - Mu0)*a^4*l^4)*r^8 + 8*(Mu0^3 - Mu0)*a^4*m^2*n + 4*(Mu0^3 - Mu0)*a^4*m^2 + 2*((Mu0^3 - Mu0)*a^4*l^2*n^2 + 2*(Mu0^3 - Mu0)*a^4*l^2*n + (Mu0^3 - Mu0)*a^4*l^2)*r^6 - (4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4 + (4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n^2 + 2*(4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n)*r^4 - 4*((Mu0^3 - Mu0)*a^4*m*n^2 + 2*(Mu0^3 - Mu0)*a^4*m*n + (Mu0^3 - Mu0)*a^4*m)*r^2)*diff(phi_1(r), r)^2 - (4*(Mu0^3 - Mu0)*a^4*m^2*n^4 + 8*(Mu0^3 - Mu0)*a^4*m^2*n^3 + 4*(Mu0^3 - Mu0)*a^4*m^2*n^2 + ((Mu0^3 - Mu0)*a^4*l^4*n^4 + 2*(Mu0^3 - Mu0)*a^4*l^4*n^3 + (Mu0^3 - Mu0)*a^4*l^4*n^2)*r^8 + 2*((Mu0^3 - Mu0)*a^4*l^2*n^4 + 2*(Mu0^3 - Mu0)*a^4*l^2*n^3 + (Mu0^3 - Mu0)*a^4*l^2*n^2)*r^6 - ((4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n^4 + 2*(4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n^3 + (4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n^2)*r^4 - 4*((Mu0^3 - Mu0)*a^4*m*n^4 + 2*(Mu0^3 - Mu0)*a^4*m*n^3 + (Mu0^3 - Mu0)*a^4*m*n^2)*r^2)*diff(psi_1(r), r)^2 + 2*(4*(Mu0^3 - Mu0)*a^4*l^2*m - (Mu0^3 - Mu0)*a^4)*n - 2*(2*(a^4*l^4*n^4 + 4*a^4*l^4*n^3 + 6*a^4*l^4*n^2 + 4*a^4*l^4*n + a^4*l^4)*r^7 + 3*(a^4*l^2*n^4 + 4*a^4*l^2*n^3 + 6*a^4*l^2*n^2 + 4*a^4*l^2*n + a^4*l^2)*r^5 - (4*a^4*l^2*m + (4*a^4*l^2*m - a^4)*n^4 - a^4 + 4*(4*a^4*l^2*m - a^4)*n^3 + 6*(4*a^4*l^2*m - a^4)*n^2 + 4*(4*a^4*l^2*m - a^4)*n)*r^3 - 2*(a^4*m*n^4 + 4*a^4*m*n^3 + 6*a^4*m*n^2 + 4*a^4*m*n + a^4*m)*r)*diff(mu_1(r), r) - (4*a^4*m^2*n^4 + 16*a^4*m^2*n^3 + (a^4*l^4*n^4 + 4*a^4*l^4*n^3 + 6*a^4*l^4*n^2 + 4*a^4*l^4*n + a^4*l^4)*r^8 + 24*a^4*m^2*n^2 + 16*a^4*m^2*n + 2*(a^4*l^2*n^4 + 4*a^4*l^2*n^3 + 6*a^4*l^2*n^2 + 4*a^4*l^2*n + a^4*l^2)*r^6 + 4*a^4*m^2 - (4*a^4*l^2*m + (4*a^4*l^2*m - a^4)*n^4 - a^4 + 4*(4*a^4*l^2*m - a^4)*n^3 + 6*(4*a^4*l^2*m - a^4)*n^2 + 4*(4*a^4*l^2*m - a^4)*n)*r^4 - 4*(a^4*m*n^4 + 4*a^4*m*n^3 + 6*a^4*m*n^2 + 4*a^4*m*n + a^4*m)*r^2)*diff(mu_1(r), r, r))/((Mu0^2 - 1)*l^2*r^4 + (Mu0^2 - 1)*r^2 - 2*(Mu0^2 - 1)*m) == 0"
]
},
"execution_count": 56,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_mu1 = eqs[2]\n",
"eq_mu1"
]
},
{
"cell_type": "code",
"execution_count": 57,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\left({\\mu_0}^{2} - 1\\right)} {\\ell}^{2} r^{4} + {\\left({\\mu_0}^{2} - 1\\right)} r^{2} - 2 \\, {\\left({\\mu_0}^{2} - 1\\right)} m$$"
],
"text/plain": [
"(Mu0^2 - 1)*l^2*r^4 + (Mu0^2 - 1)*r^2 - 2*(Mu0^2 - 1)*m"
]
},
"execution_count": 57,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_mu1.lhs().denominator().simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 58,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"eq_mu1 = eq_mu1.lhs().numerator().simplify_full() == 0\n",
"#eq_mu1"
]
},
{
"cell_type": "code",
"execution_count": 59,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{4} - 3 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{3} - 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4}\\right)} r^{4} - 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{3} + {\\mu_0}^{3} - {\\left({\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4}\\right)} r^{8} + 2 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} n + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2}\\right)} r^{6} + 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m^{2} n^{2} - {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{2} + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n + {\\mu_0}\\right)} r^{4} + 8 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m^{2} n + 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m^{2} - 4 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m n + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m\\right)} r^{2}\\right)} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right)^{2} + {\\left({\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{2}\\right)} r^{8} + 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m^{2} n^{4} + 2 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} n^{2}\\right)} r^{6} + 8 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m^{2} n^{3} + 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m^{2} n^{2} - {\\left({\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{4} + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{3} + {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{2}\\right)} r^{4} - 4 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} m n^{2}\\right)} r^{2}\\right)} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)^{2} - 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n + 2 \\, {\\left(2 \\, {\\left({\\ell}^{4} n^{4} + 4 \\, {\\ell}^{4} n^{3} + 6 \\, {\\ell}^{4} n^{2} + 4 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{7} + 3 \\, {\\left({\\ell}^{2} n^{4} + 4 \\, {\\ell}^{2} n^{3} + 6 \\, {\\ell}^{2} n^{2} + 4 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{5} - {\\left({\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{4} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{3} + 4 \\, {\\ell}^{2} m + 6 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{3} - 2 \\, {\\left(m n^{4} + 4 \\, m n^{3} + 6 \\, m n^{2} + 4 \\, m n + m\\right)} r\\right)} \\frac{\\partial}{\\partial r}\\mu_{1}\\left(r\\right) + {\\left({\\left({\\ell}^{4} n^{4} + 4 \\, {\\ell}^{4} n^{3} + 6 \\, {\\ell}^{4} n^{2} + 4 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{8} + 2 \\, {\\left({\\ell}^{2} n^{4} + 4 \\, {\\ell}^{2} n^{3} + 6 \\, {\\ell}^{2} n^{2} + 4 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{6} + 4 \\, m^{2} n^{4} + 16 \\, m^{2} n^{3} - {\\left({\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{4} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{3} + 4 \\, {\\ell}^{2} m + 6 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{4} + 24 \\, m^{2} n^{2} + 16 \\, m^{2} n - 4 \\, {\\left(m n^{4} + 4 \\, m n^{3} + 6 \\, m n^{2} + 4 \\, m n + m\\right)} r^{2} + 4 \\, m^{2}\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\mu_{1}\\left(r\\right) - {\\mu_0} = 0$$"
],
"text/plain": [
"(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^4 - 3*((Mu0^3 - Mu0)*l^4*n^4 + 2*(Mu0^3 - Mu0)*l^4*n^3 - 2*(Mu0^3 - Mu0)*l^4*n - (Mu0^3 - Mu0)*l^4)*r^4 - 4*(Mu0^3 - Mu0)*l^2*m + 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^3 + Mu0^3 - (((Mu0^3 - Mu0)*l^4*n^2 + 2*(Mu0^3 - Mu0)*l^4*n + (Mu0^3 - Mu0)*l^4)*r^8 + 2*((Mu0^3 - Mu0)*l^2*n^2 + 2*(Mu0^3 - Mu0)*l^2*n + (Mu0^3 - Mu0)*l^2)*r^6 + 4*(Mu0^3 - Mu0)*m^2*n^2 - (4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + (4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^2 + 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n + Mu0)*r^4 + 8*(Mu0^3 - Mu0)*m^2*n + 4*(Mu0^3 - Mu0)*m^2 - 4*((Mu0^3 - Mu0)*m*n^2 + 2*(Mu0^3 - Mu0)*m*n + (Mu0^3 - Mu0)*m)*r^2)*diff(phi_1(r), r)^2 + (((Mu0^3 - Mu0)*l^4*n^4 + 2*(Mu0^3 - Mu0)*l^4*n^3 + (Mu0^3 - Mu0)*l^4*n^2)*r^8 + 4*(Mu0^3 - Mu0)*m^2*n^4 + 2*((Mu0^3 - Mu0)*l^2*n^4 + 2*(Mu0^3 - Mu0)*l^2*n^3 + (Mu0^3 - Mu0)*l^2*n^2)*r^6 + 8*(Mu0^3 - Mu0)*m^2*n^3 + 4*(Mu0^3 - Mu0)*m^2*n^2 - ((4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^4 + 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^3 + (4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^2)*r^4 - 4*((Mu0^3 - Mu0)*m*n^4 + 2*(Mu0^3 - Mu0)*m*n^3 + (Mu0^3 - Mu0)*m*n^2)*r^2)*diff(psi_1(r), r)^2 - 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n + 2*(2*(l^4*n^4 + 4*l^4*n^3 + 6*l^4*n^2 + 4*l^4*n + l^4)*r^7 + 3*(l^2*n^4 + 4*l^2*n^3 + 6*l^2*n^2 + 4*l^2*n + l^2)*r^5 - ((4*l^2*m - 1)*n^4 + 4*(4*l^2*m - 1)*n^3 + 4*l^2*m + 6*(4*l^2*m - 1)*n^2 + 4*(4*l^2*m - 1)*n - 1)*r^3 - 2*(m*n^4 + 4*m*n^3 + 6*m*n^2 + 4*m*n + m)*r)*diff(mu_1(r), r) + ((l^4*n^4 + 4*l^4*n^3 + 6*l^4*n^2 + 4*l^4*n + l^4)*r^8 + 2*(l^2*n^4 + 4*l^2*n^3 + 6*l^2*n^2 + 4*l^2*n + l^2)*r^6 + 4*m^2*n^4 + 16*m^2*n^3 - ((4*l^2*m - 1)*n^4 + 4*(4*l^2*m - 1)*n^3 + 4*l^2*m + 6*(4*l^2*m - 1)*n^2 + 4*(4*l^2*m - 1)*n - 1)*r^4 + 24*m^2*n^2 + 16*m^2*n - 4*(m*n^4 + 4*m*n^3 + 6*m*n^2 + 4*m*n + m)*r^2 + 4*m^2)*diff(mu_1(r), r, r) - Mu0 == 0"
]
},
"execution_count": 59,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_mu1 = (eq_mu1/a^4).simplify_full()\n",
"eq_mu1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We plug the solutions obtained previously for $\\phi_1(r)$ and $\\psi_1(r)$ in this equation:"
]
},
{
"cell_type": "code",
"execution_count": 60,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{4} - 3 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{3} - 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4}\\right)} r^{4} - 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{3} + {\\mu_0}^{3} - {\\left({\\mu_0}^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n - {\\mu_0}\\right)} {\\mathfrak{p}}^{2} + {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{2}\\right)} {\\mathfrak{q}}^{2} - 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n + 2 \\, {\\left(2 \\, {\\left({\\ell}^{4} n^{4} + 4 \\, {\\ell}^{4} n^{3} + 6 \\, {\\ell}^{4} n^{2} + 4 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{7} + 3 \\, {\\left({\\ell}^{2} n^{4} + 4 \\, {\\ell}^{2} n^{3} + 6 \\, {\\ell}^{2} n^{2} + 4 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{5} - {\\left({\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{4} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{3} + 4 \\, {\\ell}^{2} m + 6 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{3} - 2 \\, {\\left(m n^{4} + 4 \\, m n^{3} + 6 \\, m n^{2} + 4 \\, m n + m\\right)} r\\right)} \\frac{\\partial}{\\partial r}\\mu_{1}\\left(r\\right) + {\\left({\\left({\\ell}^{4} n^{4} + 4 \\, {\\ell}^{4} n^{3} + 6 \\, {\\ell}^{4} n^{2} + 4 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{8} + 2 \\, {\\left({\\ell}^{2} n^{4} + 4 \\, {\\ell}^{2} n^{3} + 6 \\, {\\ell}^{2} n^{2} + 4 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{6} + 4 \\, m^{2} n^{4} + 16 \\, m^{2} n^{3} - {\\left({\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{4} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{3} + 4 \\, {\\ell}^{2} m + 6 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{4} + 24 \\, m^{2} n^{2} + 16 \\, m^{2} n - 4 \\, {\\left(m n^{4} + 4 \\, m n^{3} + 6 \\, m n^{2} + 4 \\, m n + m\\right)} r^{2} + 4 \\, m^{2}\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\mu_{1}\\left(r\\right) - {\\mu_0} = 0$$"
],
"text/plain": [
"(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^4 - 3*((Mu0^3 - Mu0)*l^4*n^4 + 2*(Mu0^3 - Mu0)*l^4*n^3 - 2*(Mu0^3 - Mu0)*l^4*n - (Mu0^3 - Mu0)*l^4)*r^4 - 4*(Mu0^3 - Mu0)*l^2*m + 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^3 + Mu0^3 - (Mu0^3 + (Mu0^3 - Mu0)*n^2 + 2*(Mu0^3 - Mu0)*n - Mu0)*pf^2 + ((Mu0^3 - Mu0)*n^4 + 2*(Mu0^3 - Mu0)*n^3 + (Mu0^3 - Mu0)*n^2)*qf^2 - 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n + 2*(2*(l^4*n^4 + 4*l^4*n^3 + 6*l^4*n^2 + 4*l^4*n + l^4)*r^7 + 3*(l^2*n^4 + 4*l^2*n^3 + 6*l^2*n^2 + 4*l^2*n + l^2)*r^5 - ((4*l^2*m - 1)*n^4 + 4*(4*l^2*m - 1)*n^3 + 4*l^2*m + 6*(4*l^2*m - 1)*n^2 + 4*(4*l^2*m - 1)*n - 1)*r^3 - 2*(m*n^4 + 4*m*n^3 + 6*m*n^2 + 4*m*n + m)*r)*diff(mu_1(r), r) + ((l^4*n^4 + 4*l^4*n^3 + 6*l^4*n^2 + 4*l^4*n + l^4)*r^8 + 2*(l^2*n^4 + 4*l^2*n^3 + 6*l^2*n^2 + 4*l^2*n + l^2)*r^6 + 4*m^2*n^4 + 16*m^2*n^3 - ((4*l^2*m - 1)*n^4 + 4*(4*l^2*m - 1)*n^3 + 4*l^2*m + 6*(4*l^2*m - 1)*n^2 + 4*(4*l^2*m - 1)*n - 1)*r^4 + 24*m^2*n^2 + 16*m^2*n - 4*(m*n^4 + 4*m*n^3 + 6*m*n^2 + 4*m*n + m)*r^2 + 4*m^2)*diff(mu_1(r), r, r) - Mu0 == 0"
]
},
"execution_count": 60,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_mu1 = eq_mu1.substitute_function(phi_1, phi1_sol).substitute_function(psi_1, psi1_sol)\n",
"eq_mu1 = eq_mu1.simplify_full()\n",
"eq_mu1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Check of Eq. (4.9)"
]
},
{
"cell_type": "code",
"execution_count": 61,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{4} - 3 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{3} - 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4}\\right)} r^{4} - 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m + 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{3} + {\\mu_0}^{3} - {\\left({\\mu_0}^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{2} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n - {\\mu_0}\\right)} {\\mathfrak{p}}^{2} + {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{4} + 2 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{3} + {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{2}\\right)} {\\mathfrak{q}}^{2} - 2 \\, {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n + 2 \\, {\\left(2 \\, {\\left({\\ell}^{4} n^{4} + 4 \\, {\\ell}^{4} n^{3} + 6 \\, {\\ell}^{4} n^{2} + 4 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{7} + 3 \\, {\\left({\\ell}^{2} n^{4} + 4 \\, {\\ell}^{2} n^{3} + 6 \\, {\\ell}^{2} n^{2} + 4 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{5} - {\\left({\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{4} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{3} + 4 \\, {\\ell}^{2} m + 6 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{3} - 2 \\, {\\left(m n^{4} + 4 \\, m n^{3} + 6 \\, m n^{2} + 4 \\, m n + m\\right)} r\\right)} \\frac{\\partial}{\\partial r}\\mu_{1}\\left(r\\right) + {\\left({\\left({\\ell}^{4} n^{4} + 4 \\, {\\ell}^{4} n^{3} + 6 \\, {\\ell}^{4} n^{2} + 4 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{8} + 2 \\, {\\left({\\ell}^{2} n^{4} + 4 \\, {\\ell}^{2} n^{3} + 6 \\, {\\ell}^{2} n^{2} + 4 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{6} + 4 \\, m^{2} n^{4} + 16 \\, m^{2} n^{3} - {\\left({\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{4} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{3} + 4 \\, {\\ell}^{2} m + 6 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 4 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{4} + 24 \\, m^{2} n^{2} + 16 \\, m^{2} n - 4 \\, {\\left(m n^{4} + 4 \\, m n^{3} + 6 \\, m n^{2} + 4 \\, m n + m\\right)} r^{2} + 4 \\, m^{2}\\right)} \\frac{\\partial^{2}}{(\\partial r)^{2}}\\mu_{1}\\left(r\\right) - {\\mu_0}$$"
],
"text/plain": [
"(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^4 - 3*((Mu0^3 - Mu0)*l^4*n^4 + 2*(Mu0^3 - Mu0)*l^4*n^3 - 2*(Mu0^3 - Mu0)*l^4*n - (Mu0^3 - Mu0)*l^4)*r^4 - 4*(Mu0^3 - Mu0)*l^2*m + 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^3 + Mu0^3 - (Mu0^3 + (Mu0^3 - Mu0)*n^2 + 2*(Mu0^3 - Mu0)*n - Mu0)*pf^2 + ((Mu0^3 - Mu0)*n^4 + 2*(Mu0^3 - Mu0)*n^3 + (Mu0^3 - Mu0)*n^2)*qf^2 - 2*(4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n + 2*(2*(l^4*n^4 + 4*l^4*n^3 + 6*l^4*n^2 + 4*l^4*n + l^4)*r^7 + 3*(l^2*n^4 + 4*l^2*n^3 + 6*l^2*n^2 + 4*l^2*n + l^2)*r^5 - ((4*l^2*m - 1)*n^4 + 4*(4*l^2*m - 1)*n^3 + 4*l^2*m + 6*(4*l^2*m - 1)*n^2 + 4*(4*l^2*m - 1)*n - 1)*r^3 - 2*(m*n^4 + 4*m*n^3 + 6*m*n^2 + 4*m*n + m)*r)*diff(mu_1(r), r) + ((l^4*n^4 + 4*l^4*n^3 + 6*l^4*n^2 + 4*l^4*n + l^4)*r^8 + 2*(l^2*n^4 + 4*l^2*n^3 + 6*l^2*n^2 + 4*l^2*n + l^2)*r^6 + 4*m^2*n^4 + 16*m^2*n^3 - ((4*l^2*m - 1)*n^4 + 4*(4*l^2*m - 1)*n^3 + 4*l^2*m + 6*(4*l^2*m - 1)*n^2 + 4*(4*l^2*m - 1)*n - 1)*r^4 + 24*m^2*n^2 + 16*m^2*n - 4*(m*n^4 + 4*m*n^3 + 6*m*n^2 + 4*m*n + m)*r^2 + 4*m^2)*diff(mu_1(r), r, r) - Mu0"
]
},
"execution_count": 61,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"lhs = eq_mu1.lhs()\n",
"lhs = lhs.simplify_full()\n",
"lhs"
]
},
{
"cell_type": "code",
"execution_count": 62,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)}^{2} {\\left(n + 1\\right)}^{4}$$"
],
"text/plain": [
"(l^2*r^4 + r^2 - 2*m)^2*(n + 1)^4"
]
},
"execution_count": 62,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s = lhs.coefficient(diff(mu_1(r), r, 2)) # coefficient of mu_1''\n",
"s.factor()"
]
},
{
"cell_type": "code",
"execution_count": 63,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{{\\left({\\mu_0}^{3} - {\\mu_0}\\right)} n^{2} {\\mathfrak{q}}^{2} - 3 \\, {\\left({\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4} n^{2} - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{4}\\right)} r^{4} - 4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m + {\\mu_0}^{3} + {\\left(4 \\, {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\ell}^{2} m - {\\mu_0}^{3} + {\\mu_0}\\right)} n^{2} - {\\left({\\mu_0}^{3} - {\\mu_0}\\right)} {\\mathfrak{p}}^{2} + 2 \\, {\\left(2 \\, {\\left({\\ell}^{4} n^{2} + 2 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{7} + 3 \\, {\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{5} - {\\left(4 \\, {\\ell}^{2} m + {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 2 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{3} - 2 \\, {\\left(m n^{2} + 2 \\, m n + m\\right)} r\\right)} \\frac{\\partial}{\\partial r}\\mu_{1}\\left(r\\right) - {\\mu_0}}{{\\left({\\ell}^{4} n^{2} + 2 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{8} + 2 \\, {\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{6} - {\\left(4 \\, {\\ell}^{2} m + {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n^{2} + 2 \\, {\\left(4 \\, {\\ell}^{2} m - 1\\right)} n - 1\\right)} r^{4} + 4 \\, m^{2} n^{2} + 8 \\, m^{2} n - 4 \\, {\\left(m n^{2} + 2 \\, m n + m\\right)} r^{2} + 4 \\, m^{2}}$$"
],
"text/plain": [
"((Mu0^3 - Mu0)*n^2*qf^2 - 3*((Mu0^3 - Mu0)*l^4*n^2 - (Mu0^3 - Mu0)*l^4)*r^4 - 4*(Mu0^3 - Mu0)*l^2*m + Mu0^3 + (4*(Mu0^3 - Mu0)*l^2*m - Mu0^3 + Mu0)*n^2 - (Mu0^3 - Mu0)*pf^2 + 2*(2*(l^4*n^2 + 2*l^4*n + l^4)*r^7 + 3*(l^2*n^2 + 2*l^2*n + l^2)*r^5 - (4*l^2*m + (4*l^2*m - 1)*n^2 + 2*(4*l^2*m - 1)*n - 1)*r^3 - 2*(m*n^2 + 2*m*n + m)*r)*diff(mu_1(r), r) - Mu0)/((l^4*n^2 + 2*l^4*n + l^4)*r^8 + 2*(l^2*n^2 + 2*l^2*n + l^2)*r^6 - (4*l^2*m + (4*l^2*m - 1)*n^2 + 2*(4*l^2*m - 1)*n - 1)*r^4 + 4*m^2*n^2 + 8*m^2*n - 4*(m*n^2 + 2*m*n + m)*r^2 + 4*m^2)"
]
},
"execution_count": 63,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s1 = (lhs/s - diff(mu_1(r), r, 2)).simplify_full()\n",
"s1"
]
},
{
"cell_type": "code",
"execution_count": 64,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{2 \\, {\\left(2 \\, {\\ell}^{2} r^{2} + 1\\right)} r}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}$$"
],
"text/plain": [
"2*(2*l^2*r^2 + 1)*r/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 64,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"b1 = s1.coefficient(diff(mu_1(r), r)).factor()\n",
"b1"
]
},
{
"cell_type": "code",
"execution_count": 65,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{{\\left(3 \\, {\\ell}^{4} n^{2} r^{4} - 3 \\, {\\ell}^{4} r^{4} - 4 \\, {\\ell}^{2} m n^{2} - n^{2} {\\mathfrak{q}}^{2} + 4 \\, {\\ell}^{2} m + n^{2} + {\\mathfrak{p}}^{2} - 1\\right)} {\\left({\\mu_0} + 1\\right)} {\\left({\\mu_0} - 1\\right)} {\\mu_0}}{{\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)}^{2} {\\left(n + 1\\right)}^{2}}$$"
],
"text/plain": [
"-(3*l^4*n^2*r^4 - 3*l^4*r^4 - 4*l^2*m*n^2 - n^2*qf^2 + 4*l^2*m + n^2 + pf^2 - 1)*(Mu0 + 1)*(Mu0 - 1)*Mu0/((l^2*r^4 + r^2 - 2*m)^2*(n + 1)^2)"
]
},
"execution_count": 65,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"b2 = (s1 - b1*diff(mu_1(r), r)).simplify_full().factor()\n",
"b2"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The equation for $\\mu_1$ is thus:"
]
},
{
"cell_type": "code",
"execution_count": 66,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{2 \\, {\\left(2 \\, {\\ell}^{2} r^{2} + 1\\right)} r \\frac{\\partial}{\\partial r}\\mu_{1}\\left(r\\right)}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m} - \\frac{{\\left(3 \\, {\\ell}^{4} n^{2} r^{4} - 3 \\, {\\ell}^{4} r^{4} - 4 \\, {\\ell}^{2} m n^{2} - n^{2} {\\mathfrak{q}}^{2} + 4 \\, {\\ell}^{2} m + n^{2} + {\\mathfrak{p}}^{2} - 1\\right)} {\\left({\\mu_0} + 1\\right)} {\\left({\\mu_0} - 1\\right)} {\\mu_0}}{{\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)}^{2} {\\left(n + 1\\right)}^{2}} + \\frac{\\partial^{2}}{(\\partial r)^{2}}\\mu_{1}\\left(r\\right) = 0$$"
],
"text/plain": [
"2*(2*l^2*r^2 + 1)*r*diff(mu_1(r), r)/(l^2*r^4 + r^2 - 2*m) - (3*l^4*n^2*r^4 - 3*l^4*r^4 - 4*l^2*m*n^2 - n^2*qf^2 + 4*l^2*m + n^2 + pf^2 - 1)*(Mu0 + 1)*(Mu0 - 1)*Mu0/((l^2*r^4 + r^2 - 2*m)^2*(n + 1)^2) + diff(mu_1(r), r, r) == 0"
]
},
"execution_count": 66,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_mu1 = diff(mu_1(r), r, 2) + b1*diff(mu_1(r), r) + b2 == 0\n",
"eq_mu1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us define\n",
"$$ \\Theta_2 := 2 \\Theta_0$$"
]
},
{
"cell_type": "code",
"execution_count": 67,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"Th2 = var('Th2', latex_name=r'\\Theta_2', \n",
" domain='real')"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Given that \n",
"$$ \\mu_1(r) = - \\sin\\Theta_0 \\; \\theta_1(r) = - \\sqrt{1-\\mu_0^2} \\; \\theta_1(r)$$\n",
"and\n",
"$$\\sin2\\Theta_0 = 2\\mu_0\\sqrt{1-\\mu_0^2},$$\n",
"we get the equation for $\\Upsilon := \\theta_1' = - \\frac{\\mu_1'}{\\sqrt{1 - \\mu_0}}$:"
]
},
{
"cell_type": "code",
"execution_count": 68,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{2 \\, {\\left(2 \\, {\\ell}^{2} r^{2} + 1\\right)} r \\Upsilon\\left(r\\right)}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m} - \\frac{{\\left(3 \\, {\\ell}^{4} n^{2} r^{4} - 3 \\, {\\ell}^{4} r^{4} - 4 \\, {\\ell}^{2} m n^{2} - n^{2} {\\mathfrak{q}}^{2} + 4 \\, {\\ell}^{2} m + n^{2} + {\\mathfrak{p}}^{2} - 1\\right)} \\sin\\left({\\Theta_2}\\right)}{2 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)}^{2} {\\left(n + 1\\right)}^{2}} + \\frac{\\partial}{\\partial r}\\Upsilon\\left(r\\right) = 0$$"
],
"text/plain": [
"2*(2*l^2*r^2 + 1)*r*Y(r)/(l^2*r^4 + r^2 - 2*m) - 1/2*(3*l^4*n^2*r^4 - 3*l^4*r^4 - 4*l^2*m*n^2 - n^2*qf^2 + 4*l^2*m + n^2 + pf^2 - 1)*sin(Th2)/((l^2*r^4 + r^2 - 2*m)^2*(n + 1)^2) + diff(Y(r), r) == 0"
]
},
"execution_count": 68,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y = function('Y', latex_name=r'\\Upsilon')\n",
"eq_Y = diff(Y(r), r) + b1*Y(r) \\\n",
" - (b2/(2*(1-Mu0^2)*Mu0)*sin(Th2)).factor() == 0\n",
"eq_Y"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"This agrees with Eq. (4.9) of the paper."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Solving the equation for $\\Upsilon := \\theta_1'$"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We use the function `desolve` to solve the differential equation for $\\Upsilon$:"
]
},
{
"cell_type": "code",
"execution_count": 69,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"Y_sol(r) = desolve(eq_Y, Y(r), ivar=r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The solution involves an integral that SageMath is not capable to evaluate with the default integrator. Trying to display `Y_sol` would make SageMath hang. Instead, we print `Y_sol` to get the unvaluated form of the integral, in order to compute it by means of FriCAS:"
]
},
{
"cell_type": "code",
"execution_count": 70,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1/2*(2*_C + 3*(l^2*n*sin(Th2) - l^2*sin(Th2))*r/(n + 1) - integrate((n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 + 3*(l^2*n^2 - l^2)*r^2 - pf^2 + 1)/(l^2*r^4 + r^2 - 2*m), r)*sin(Th2)/(n^2 + 2*n + 1))/(l^2*r^4 + r^2 - 2*m)\n"
]
}
],
"source": [
"print(Y_sol(r))"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The solution involves some constant, denoted `_C` by SageMath. We rename it `C_1` and \n",
"rewrite the above solution as"
]
},
{
"cell_type": "code",
"execution_count": 71,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{2 \\, C_{1} + \\frac{3 \\, {\\left({\\ell}^{2} n \\sin\\left({\\Theta_2}\\right) - {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} r}{n + 1} - \\frac{{\\rm Integ}\\left(r\\right) \\sin\\left({\\Theta_2}\\right)}{n^{2} + 2 \\, n + 1}}{2 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)}}$$"
],
"text/plain": [
"1/2*(2*C_1 + 3*(l^2*n*sin(Th2) - l^2*sin(Th2))*r/(n + 1) - Integ(r)*sin(Th2)/(n^2 + 2*n + 1))/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 71,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"C_1 = var('C_1')\n",
"Integ(r) = function('Integ')(r)\n",
"Y_sol0(r) = 1/2*(2*C_1 + 3*(l^2*n*sin(Th2) - l^2*sin(Th2))*r/(n + 1) \\\n",
" - Integ(r)*sin(Th2)/(n^2 + 2*n + 1))/(l^2*r^4 + r^2 - 2*m)\n",
"Y_sol0(r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"`Integ(r)` represents the integral $I(r)$, whose integrand, $F(r)$ say, is read from the\n",
"output of `print(Y_sol(r))`:"
]
},
{
"cell_type": "code",
"execution_count": 72,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{2} m - {\\left(2 \\, {\\ell}^{2} m + 1\\right)} n^{2} + 3 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} r^{2} - {\\mathfrak{p}}^{2} + 1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}$$"
],
"text/plain": [
"(n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 + 3*(l^2*n^2 - l^2)*r^2 - pf^2 + 1)/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 72,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"F(r) = (n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 + 3*(l^2*n^2 - l^2)*r^2 - pf^2 + 1) \\\n",
" /(l^2*r^4 + r^2 - 2*m)\n",
"F(r)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We split the integral in two parts:\n",
"$$ I(r) = F_1 \\; s_1(r) + F_2 \\; s_2(r)$$\n",
"with \n",
"$$ s_1(r) := \\int^r \\frac{\\bar{r}^2}{\\ell^2 \\bar{r}^4 + \\bar{r}^2 - 2m} \\, \\mathrm{d}\\bar{r}, \\qquad s_2(r) := \\int^r \\frac{\\mathrm{d}\\bar{r}}{\\ell^2 \\bar{r}^4 + \\bar{r}^2 - 2m} $$\n",
"and"
]
},
{
"cell_type": "code",
"execution_count": 73,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}3 \\, {\\ell}^{2} n^{2} - 3 \\, {\\ell}^{2}$$"
],
"text/plain": [
"3*l^2*n^2 - 3*l^2"
]
},
"execution_count": 73,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"F1 = 3*(l^2*n^2 - l^2)\n",
"F1"
]
},
{
"cell_type": "code",
"execution_count": 74,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{2} m - {\\left(2 \\, {\\ell}^{2} m + 1\\right)} n^{2} - {\\mathfrak{p}}^{2} + 1$$"
],
"text/plain": [
"n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 - pf^2 + 1"
]
},
"execution_count": 74,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"F2 = n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 - pf^2 + 1\n",
"F2"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Check:"
]
},
{
"cell_type": "code",
"execution_count": 75,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\mathrm{True}$$"
],
"text/plain": [
"True"
]
},
"execution_count": 75,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"bool(F(r) == F1*r^2/(l^2*r^4 + r^2 - 2*m) + F2/(l^2*r^4 + r^2 - 2*m))"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us evaluate $s_1(r)$ by means of FriCAS:"
]
},
{
"cell_type": "code",
"execution_count": 76,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{1}{2} \\, \\sqrt{\\frac{1}{2}} \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}} \\log\\left(\\frac{\\sqrt{\\frac{1}{2}} {\\left(8 \\, {\\ell}^{4} m + {\\ell}^{2}\\right)} \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + r\\right) - \\frac{1}{2} \\, \\sqrt{\\frac{1}{2}} \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}} \\log\\left(-\\frac{\\sqrt{\\frac{1}{2}} {\\left(8 \\, {\\ell}^{4} m + {\\ell}^{2}\\right)} \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + r\\right) - \\frac{1}{2} \\, \\sqrt{\\frac{1}{2}} \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} - 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}} \\log\\left(\\frac{\\sqrt{\\frac{1}{2}} {\\left(8 \\, {\\ell}^{4} m + {\\ell}^{2}\\right)} \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} - 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + r\\right) + \\frac{1}{2} \\, \\sqrt{\\frac{1}{2}} \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} - 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}} \\log\\left(-\\frac{\\sqrt{\\frac{1}{2}} {\\left(8 \\, {\\ell}^{4} m + {\\ell}^{2}\\right)} \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{4} m + {\\ell}^{2}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} - 1}{8 \\, {\\ell}^{4} m + {\\ell}^{2}}}}{\\sqrt{8 \\, {\\ell}^{6} m + {\\ell}^{4}}} + r\\right)$$"
],
"text/plain": [
"1/2*sqrt(1/2)*sqrt(-((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) + 1)/(8*l^4*m + l^2))*log(sqrt(1/2)*(8*l^4*m + l^2)*sqrt(-((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) + 1)/(8*l^4*m + l^2))/sqrt(8*l^6*m + l^4) + r) - 1/2*sqrt(1/2)*sqrt(-((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) + 1)/(8*l^4*m + l^2))*log(-sqrt(1/2)*(8*l^4*m + l^2)*sqrt(-((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) + 1)/(8*l^4*m + l^2))/sqrt(8*l^6*m + l^4) + r) - 1/2*sqrt(1/2)*sqrt(((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) - 1)/(8*l^4*m + l^2))*log(sqrt(1/2)*(8*l^4*m + l^2)*sqrt(((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) - 1)/(8*l^4*m + l^2))/sqrt(8*l^6*m + l^4) + r) + 1/2*sqrt(1/2)*sqrt(((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) - 1)/(8*l^4*m + l^2))*log(-sqrt(1/2)*(8*l^4*m + l^2)*sqrt(((8*l^4*m + l^2)/sqrt(8*l^6*m + l^4) - 1)/(8*l^4*m + l^2))/sqrt(8*l^6*m + l^4) + r)"
]
},
"execution_count": 76,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s1 = integrate(r^2/(l^2*r^4 + r^2 - 2*m), r, algorithm='fricas')\n",
"s1"
]
},
{
"cell_type": "code",
"execution_count": 77,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{\\sqrt{2} \\sqrt{8 \\, {\\ell}^{2} m - \\sqrt{8 \\, {\\ell}^{2} m + 1} + 1} \\log\\left(\\frac{\\sqrt{2} {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell} r - \\sqrt{8 \\, {\\ell}^{2} m - \\sqrt{8 \\, {\\ell}^{2} m + 1} + 1}}{\\sqrt{2} {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell} r + \\sqrt{8 \\, {\\ell}^{2} m - \\sqrt{8 \\, {\\ell}^{2} m + 1} + 1}}\\right) + \\sqrt{2} \\sqrt{-8 \\, {\\ell}^{2} m - \\sqrt{8 \\, {\\ell}^{2} m + 1} - 1} \\log\\left(\\frac{\\sqrt{2} {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell} r + \\sqrt{-8 \\, {\\ell}^{2} m - \\sqrt{8 \\, {\\ell}^{2} m + 1} - 1}}{\\sqrt{2} {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell} r - \\sqrt{-8 \\, {\\ell}^{2} m - \\sqrt{8 \\, {\\ell}^{2} m + 1} - 1}}\\right)}{4 \\, {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{3}{4}} {\\ell}}$$"
],
"text/plain": [
"1/4*(sqrt(2)*sqrt(8*l^2*m - sqrt(8*l^2*m + 1) + 1)*log((sqrt(2)*(8*l^2*m + 1)^(1/4)*l*r - sqrt(8*l^2*m - sqrt(8*l^2*m + 1) + 1))/(sqrt(2)*(8*l^2*m + 1)^(1/4)*l*r + sqrt(8*l^2*m - sqrt(8*l^2*m + 1) + 1))) + sqrt(2)*sqrt(-8*l^2*m - sqrt(8*l^2*m + 1) - 1)*log((sqrt(2)*(8*l^2*m + 1)^(1/4)*l*r + sqrt(-8*l^2*m - sqrt(8*l^2*m + 1) - 1))/(sqrt(2)*(8*l^2*m + 1)^(1/4)*l*r - sqrt(-8*l^2*m - sqrt(8*l^2*m + 1) - 1))))/((8*l^2*m + 1)^(3/4)*l)"
]
},
"execution_count": 77,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s1 = s1.canonicalize_radical().simplify_log()\n",
"s1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Check:"
]
},
{
"cell_type": "code",
"execution_count": 78,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{r^{2}}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}$$"
],
"text/plain": [
"r^2/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 78,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"diff(s1, r).simplify_full()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Similarly, we evaluate $s_2(r)$ by means of FriCAS:"
]
},
{
"cell_type": "code",
"execution_count": 79,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{1}{4} \\, \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1}{8 \\, {\\ell}^{2} m^{2} + m}} \\log\\left(2 \\, {\\ell}^{2} r + \\frac{1}{2} \\, {\\left(8 \\, {\\ell}^{2} m - \\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1\\right)} \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1}{8 \\, {\\ell}^{2} m^{2} + m}}\\right) + \\frac{1}{4} \\, \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1}{8 \\, {\\ell}^{2} m^{2} + m}} \\log\\left(2 \\, {\\ell}^{2} r - \\frac{1}{2} \\, {\\left(8 \\, {\\ell}^{2} m - \\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1\\right)} \\sqrt{\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1}{8 \\, {\\ell}^{2} m^{2} + m}}\\right) - \\frac{1}{4} \\, \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} - 1}{8 \\, {\\ell}^{2} m^{2} + m}} \\log\\left(2 \\, {\\ell}^{2} r + \\frac{1}{2} \\, {\\left(8 \\, {\\ell}^{2} m + \\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1\\right)} \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} - 1}{8 \\, {\\ell}^{2} m^{2} + m}}\\right) + \\frac{1}{4} \\, \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} - 1}{8 \\, {\\ell}^{2} m^{2} + m}} \\log\\left(2 \\, {\\ell}^{2} r - \\frac{1}{2} \\, {\\left(8 \\, {\\ell}^{2} m + \\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} + 1\\right)} \\sqrt{-\\frac{\\frac{8 \\, {\\ell}^{2} m^{2} + m}{\\sqrt{8 \\, {\\ell}^{2} m^{3} + m^{2}}} - 1}{8 \\, {\\ell}^{2} m^{2} + m}}\\right)$$"
],
"text/plain": [
"-1/4*sqrt(((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)/(8*l^2*m^2 + m))*log(2*l^2*r + 1/2*(8*l^2*m - (8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)*sqrt(((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)/(8*l^2*m^2 + m))) + 1/4*sqrt(((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)/(8*l^2*m^2 + m))*log(2*l^2*r - 1/2*(8*l^2*m - (8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)*sqrt(((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)/(8*l^2*m^2 + m))) - 1/4*sqrt(-((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) - 1)/(8*l^2*m^2 + m))*log(2*l^2*r + 1/2*(8*l^2*m + (8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)*sqrt(-((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) - 1)/(8*l^2*m^2 + m))) + 1/4*sqrt(-((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) - 1)/(8*l^2*m^2 + m))*log(2*l^2*r - 1/2*(8*l^2*m + (8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) + 1)*sqrt(-((8*l^2*m^2 + m)/sqrt(8*l^2*m^3 + m^2) - 1)/(8*l^2*m^2 + m)))"
]
},
"execution_count": 79,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2 = integrate(1/(l^2*r^4 + r^2 - 2*m), r, algorithm='fricas')\n",
"s2"
]
},
{
"cell_type": "code",
"execution_count": 80,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{\\sqrt{-8 \\, {\\ell}^{2} m + \\sqrt{8 \\, {\\ell}^{2} m + 1} - 1} \\log\\left(\\frac{4 \\, {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell}^{2} \\sqrt{m} r - \\sqrt{-8 \\, {\\ell}^{2} m + \\sqrt{8 \\, {\\ell}^{2} m + 1} - 1} {\\left(\\sqrt{8 \\, {\\ell}^{2} m + 1} + 1\\right)}}{4 \\, {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell}^{2} \\sqrt{m} r + \\sqrt{-8 \\, {\\ell}^{2} m + \\sqrt{8 \\, {\\ell}^{2} m + 1} - 1} {\\left(\\sqrt{8 \\, {\\ell}^{2} m + 1} + 1\\right)}}\\right) + \\sqrt{8 \\, {\\ell}^{2} m + \\sqrt{8 \\, {\\ell}^{2} m + 1} + 1} \\log\\left(\\frac{4 \\, {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell}^{2} \\sqrt{m} r - \\sqrt{8 \\, {\\ell}^{2} m + \\sqrt{8 \\, {\\ell}^{2} m + 1} + 1} {\\left(\\sqrt{8 \\, {\\ell}^{2} m + 1} - 1\\right)}}{4 \\, {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{1}{4}} {\\ell}^{2} \\sqrt{m} r + \\sqrt{8 \\, {\\ell}^{2} m + \\sqrt{8 \\, {\\ell}^{2} m + 1} + 1} {\\left(\\sqrt{8 \\, {\\ell}^{2} m + 1} - 1\\right)}}\\right)}{4 \\, {\\left(8 \\, {\\ell}^{2} m + 1\\right)}^{\\frac{3}{4}} \\sqrt{m}}$$"
],
"text/plain": [
"1/4*(sqrt(-8*l^2*m + sqrt(8*l^2*m + 1) - 1)*log((4*(8*l^2*m + 1)^(1/4)*l^2*sqrt(m)*r - sqrt(-8*l^2*m + sqrt(8*l^2*m + 1) - 1)*(sqrt(8*l^2*m + 1) + 1))/(4*(8*l^2*m + 1)^(1/4)*l^2*sqrt(m)*r + sqrt(-8*l^2*m + sqrt(8*l^2*m + 1) - 1)*(sqrt(8*l^2*m + 1) + 1))) + sqrt(8*l^2*m + sqrt(8*l^2*m + 1) + 1)*log((4*(8*l^2*m + 1)^(1/4)*l^2*sqrt(m)*r - sqrt(8*l^2*m + sqrt(8*l^2*m + 1) + 1)*(sqrt(8*l^2*m + 1) - 1))/(4*(8*l^2*m + 1)^(1/4)*l^2*sqrt(m)*r + sqrt(8*l^2*m + sqrt(8*l^2*m + 1) + 1)*(sqrt(8*l^2*m + 1) - 1))))/((8*l^2*m + 1)^(3/4)*sqrt(m))"
]
},
"execution_count": 80,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2 = s2.canonicalize_radical().simplify_log()\n",
"s2"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Check:"
]
},
{
"cell_type": "code",
"execution_count": 81,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}$$"
],
"text/plain": [
"1/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 81,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"diff(s2, r).simplify_full()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"In the above expressions for $s_1(r)$ and $s_2(r)$ there appears $\\sqrt{1 + 8 \\ell^2 m}$,\n",
"which can be rewritten\n",
"$$\n",
" \\sqrt{1 + 8 \\ell^2 m} = 2 \\ell^2 r_H^2 + 1 \n",
"$$\n",
"where $r_H$ is the positive root of $\\ell^2 r_H^4 + r_H^2 - 2m = 0$. More precisely, we perform the following substitution:\n",
"$$\n",
" m = \\frac{1}{2} r_H^2 (\\ell^2 r_H^2 + 1)\n",
"$$"
]
},
{
"cell_type": "code",
"execution_count": 82,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{{\\ell} {r_H} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right) + i \\, \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} \\log\\left(\\frac{{\\ell} r - i \\, \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}{{\\ell} r + i \\, \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right)}{2 \\, {\\left(2 \\, {\\ell}^{3} {r_H}^{2} + {\\ell}\\right)}}$$"
],
"text/plain": [
"-1/2*(l*rH*log((r + rH)/(r - rH)) + I*sqrt(l^2*rH^2 + 1)*log((l*r - I*sqrt(l^2*rH^2 + 1))/(l*r + I*sqrt(l^2*rH^2 + 1))))/(2*l^3*rH^2 + l)"
]
},
"execution_count": 82,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"rH = var('rH', latex_name=r'r_H', domain='real')\n",
"assume(rH > 0)\n",
"m_rH = rH^2*(l^2*rH^2 + 1)/2\n",
"s1 = s1.subs({m: m_rH}).canonicalize_radical().simplify_log()\n",
"s1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"In the second $\\log$, we recognize the $\\mathrm{arccot}$ function, via the identity\n",
"$$\n",
" \\mathrm{arccot}\\, x = \\frac{i}{2} \\ln\\left( \\frac{x - i}{x + i} \\right) . \n",
"$$\n",
"Given that $\\mathrm{arccot}\\, x = \\pi/2 - \\mathrm{arctan}\\, x$, we use this identity as\n",
"$$\n",
"i \\ln\\left( \\frac{x - i}{x + i} \\right) = - 2 \\, \\mathrm{arctan}(x) + \\pi\n",
"$$"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Thus, we perform the following substitution, disregarding the additive constant $\\pi$:"
]
},
{
"cell_type": "code",
"execution_count": 83,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{{\\ell} {r_H} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right) - 2 \\, \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right)}{2 \\, {\\left(2 \\, {\\ell}^{3} {r_H}^{2} + {\\ell}\\right)}}$$"
],
"text/plain": [
"-1/2*(l*rH*log((r + rH)/(r - rH)) - 2*sqrt(l^2*rH^2 + 1)*arctan(l*r/sqrt(l^2*rH^2 + 1)))/(2*l^3*rH^2 + l)"
]
},
"execution_count": 83,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s1 = s1.subs({I*sqrt(l^2*rH^2 + 1)*log((l*r - I*sqrt(l^2*rH^2 + 1))/(l*r + I*sqrt(l^2*rH^2 + 1))):\n",
" -2*sqrt(l^2*rH^2 + 1)*atan(l*r/sqrt(l^2*rH^2 + 1))})\n",
"s1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us check that we have indeed a primitive of $r\\mapsto \\frac{r^2}{\\ell^2 r^4 + r^2 - 2m}$:"
]
},
{
"cell_type": "code",
"execution_count": 84,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{r^{2}}{{\\ell}^{2} r^{4} - {\\ell}^{2} {r_H}^{4} + r^{2} - {r_H}^{2}}$$"
],
"text/plain": [
"r^2/(l^2*r^4 - l^2*rH^4 + r^2 - rH^2)"
]
},
"execution_count": 84,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Ds1 = diff(s1, r).simplify_full()\n",
"Ds1"
]
},
{
"cell_type": "code",
"execution_count": 85,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{r^{2}}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}$$"
],
"text/plain": [
"r^2/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 85,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"rH_m = sqrt(sqrt(1 + 8*l^2*m) - 1)/(sqrt(2)*l)\n",
"Ds1.subs({rH: rH_m}).simplify_full()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Similarly, let us express $s_2$ in terms of $r_H$:"
]
},
{
"cell_type": "code",
"execution_count": 86,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{i \\, {\\ell} {r_H} \\log\\left(\\frac{-i \\, {\\ell}^{2} {r_H}^{2} + \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} r - i}{i \\, {\\ell}^{2} {r_H}^{2} + \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} r + i}\\right) + \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} \\log\\left(\\frac{r - {r_H}}{r + {r_H}}\\right)}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{3} + {r_H}\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}$$"
],
"text/plain": [
"1/2*(I*l*rH*log((-I*l^2*rH^2 + sqrt(l^2*rH^2 + 1)*l*r - I)/(I*l^2*rH^2 + sqrt(l^2*rH^2 + 1)*l*r + I)) + sqrt(l^2*rH^2 + 1)*log((r - rH)/(r + rH)))/((2*l^2*rH^3 + rH)*sqrt(l^2*rH^2 + 1))"
]
},
"execution_count": 86,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2 = s2.subs({m: m_rH}).canonicalize_radical().simplify_log()\n",
"s2"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Again, we use the identity\n",
"$$\n",
"i \\ln\\left( \\frac{x - i}{x + i} \\right) = - 2 \\, \\mathrm{arctan}(x) + \\pi\n",
"$$\n",
"to rewrite $s_2$ as"
]
},
{
"cell_type": "code",
"execution_count": 87,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{2 \\, {\\ell} {r_H} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right) - \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} \\log\\left(\\frac{r - {r_H}}{r + {r_H}}\\right)}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{3} + {r_H}\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}$$"
],
"text/plain": [
"-1/2*(2*l*rH*arctan(l*r/sqrt(l^2*rH^2 + 1)) - sqrt(l^2*rH^2 + 1)*log((r - rH)/(r + rH)))/((2*l^2*rH^3 + rH)*sqrt(l^2*rH^2 + 1))"
]
},
"execution_count": 87,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2 = s2.subs({I*l*rH*log((-I*l^2*rH^2 + sqrt(l^2*rH^2 + 1)*l*r - I)/(I*l^2*rH^2 + sqrt(l^2*rH^2 + 1)*l*r + I)):\n",
" -2*l*rH*atan(l*r/sqrt(l^2*rH^2 + 1))})\n",
"s2"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us also replace $\\ln\\left(\\frac{r - r_H}{r + r_H}\\right)$ by $-\\ln\\left(\\frac{r + r_H}{r - r_H}\\right)$\n",
"in order to have the same log term as in $s_1(r)$:"
]
},
{
"cell_type": "code",
"execution_count": 88,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{2 \\, {\\ell} {r_H} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right) + \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right)}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{3} + {r_H}\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}$$"
],
"text/plain": [
"-1/2*(2*l*rH*arctan(l*r/sqrt(l^2*rH^2 + 1)) + sqrt(l^2*rH^2 + 1)*log((r + rH)/(r - rH)))/((2*l^2*rH^3 + rH)*sqrt(l^2*rH^2 + 1))"
]
},
"execution_count": 88,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2 = s2.subs({log((r - rH)/(r + rH)): - log((r + rH)/(r - rH))})\n",
"s2"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us check that we have indeed a primitive of $r\\mapsto \\frac{1}{\\ell^2 r^4 + r^2 - 2m}$:"
]
},
{
"cell_type": "code",
"execution_count": 89,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{1}{{\\ell}^{2} r^{4} - {\\ell}^{2} {r_H}^{4} + r^{2} - {r_H}^{2}}$$"
],
"text/plain": [
"1/(l^2*r^4 - l^2*rH^4 + r^2 - rH^2)"
]
},
"execution_count": 89,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Ds2 = diff(s2, r).simplify_full()\n",
"Ds2"
]
},
{
"cell_type": "code",
"execution_count": 90,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}$$"
],
"text/plain": [
"1/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 90,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Ds2.subs({rH: rH_m}).simplify_full()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The full integral is thus"
]
},
{
"cell_type": "code",
"execution_count": 91,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{{\\left(n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{2} m - {\\left(2 \\, {\\ell}^{2} m + 1\\right)} n^{2} + 3 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} {r_H}^{2} - {\\mathfrak{p}}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right) - 2 \\, {\\left(3 \\, {\\left({\\ell}^{3} n^{2} - {\\ell}^{3}\\right)} {r_H}^{3} - {\\left({\\ell} n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{3} m - 2 \\, {\\left({\\ell}^{3} m + 2 \\, {\\ell}\\right)} n^{2} - {\\ell} {\\mathfrak{p}}^{2} + 4 \\, {\\ell}\\right)} {r_H}\\right)} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right)}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{3} + {r_H}\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}$$"
],
"text/plain": [
"-1/2*((n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 + 3*(l^2*n^2 - l^2)*rH^2 - pf^2 + 1)*sqrt(l^2*rH^2 + 1)*log((r + rH)/(r - rH)) - 2*(3*(l^3*n^2 - l^3)*rH^3 - (l*n^2*qf^2 + 2*l^3*m - 2*(l^3*m + 2*l)*n^2 - l*pf^2 + 4*l)*rH)*arctan(l*r/sqrt(l^2*rH^2 + 1)))/((2*l^2*rH^3 + rH)*sqrt(l^2*rH^2 + 1))"
]
},
"execution_count": 91,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Integ0 = (F1*s1 + F2*s2).simplify_full()\n",
"Integ0"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"so that the solution is"
]
},
{
"cell_type": "code",
"execution_count": 92,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{2 \\, {\\left(3 \\, {\\left({\\ell}^{3} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{3} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}^{3} - {\\left({\\ell} n^{2} {\\mathfrak{q}}^{2} \\sin\\left({\\Theta_2}\\right) + 2 \\, {\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) - {\\ell} {\\mathfrak{p}}^{2} \\sin\\left({\\Theta_2}\\right) - 2 \\, {\\left({\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) + 2 \\, {\\ell} \\sin\\left({\\Theta_2}\\right)\\right)} n^{2} + 4 \\, {\\ell} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}\\right)} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right) - \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(4 \\, {\\left(2 \\, C_{1} {\\ell}^{2} n^{2} + 4 \\, C_{1} {\\ell}^{2} n + 2 \\, C_{1} {\\ell}^{2} + 3 \\, {\\left({\\ell}^{4} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{4} \\sin\\left({\\Theta_2}\\right)\\right)} r\\right)} {r_H}^{3} + 2 \\, {\\left(2 \\, C_{1} n^{2} + 4 \\, C_{1} n + 3 \\, {\\left({\\ell}^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} r + 2 \\, C_{1}\\right)} {r_H} + {\\left(n^{2} {\\mathfrak{q}}^{2} \\sin\\left({\\Theta_2}\\right) + 2 \\, {\\ell}^{2} m \\sin\\left({\\Theta_2}\\right) - {\\left(2 \\, {\\ell}^{2} m \\sin\\left({\\Theta_2}\\right) + \\sin\\left({\\Theta_2}\\right)\\right)} n^{2} + 3 \\, {\\left({\\ell}^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}^{2} - {\\mathfrak{p}}^{2} \\sin\\left({\\Theta_2}\\right) + \\sin\\left({\\Theta_2}\\right)\\right)} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right)\\right)}}{4 \\, \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(2 \\, {\\left(2 \\, {\\ell}^{2} m n^{2} - {\\left({\\ell}^{4} n^{2} + 2 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{4} + 4 \\, {\\ell}^{2} m n + 2 \\, {\\ell}^{2} m - {\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{2}\\right)} {r_H}^{3} - {\\left({\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{4} - 2 \\, m n^{2} + {\\left(n^{2} + 2 \\, n + 1\\right)} r^{2} - 4 \\, m n - 2 \\, m\\right)} {r_H}\\right)}}$$"
],
"text/plain": [
"1/4*(2*(3*(l^3*n^2*sin(Th2) - l^3*sin(Th2))*rH^3 - (l*n^2*qf^2*sin(Th2) + 2*l^3*m*sin(Th2) - l*pf^2*sin(Th2) - 2*(l^3*m*sin(Th2) + 2*l*sin(Th2))*n^2 + 4*l*sin(Th2))*rH)*arctan(l*r/sqrt(l^2*rH^2 + 1)) - sqrt(l^2*rH^2 + 1)*(4*(2*C_1*l^2*n^2 + 4*C_1*l^2*n + 2*C_1*l^2 + 3*(l^4*n^2*sin(Th2) - l^4*sin(Th2))*r)*rH^3 + 2*(2*C_1*n^2 + 4*C_1*n + 3*(l^2*n^2*sin(Th2) - l^2*sin(Th2))*r + 2*C_1)*rH + (n^2*qf^2*sin(Th2) + 2*l^2*m*sin(Th2) - (2*l^2*m*sin(Th2) + sin(Th2))*n^2 + 3*(l^2*n^2*sin(Th2) - l^2*sin(Th2))*rH^2 - pf^2*sin(Th2) + sin(Th2))*log((r + rH)/(r - rH))))/(sqrt(l^2*rH^2 + 1)*(2*(2*l^2*m*n^2 - (l^4*n^2 + 2*l^4*n + l^4)*r^4 + 4*l^2*m*n + 2*l^2*m - (l^2*n^2 + 2*l^2*n + l^2)*r^2)*rH^3 - ((l^2*n^2 + 2*l^2*n + l^2)*r^4 - 2*m*n^2 + (n^2 + 2*n + 1)*r^2 - 4*m*n - 2*m)*rH))"
]
},
"execution_count": 92,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y_sol(r) = Y_sol0(r).subs({Integ(r): Integ0}).simplify_full()\n",
"Y_sol(r)"
]
},
{
"cell_type": "code",
"execution_count": 93,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-2 \\, {\\left(3 \\, {\\left({\\ell}^{3} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{3} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}^{3} - {\\left({\\ell} n^{2} {\\mathfrak{q}}^{2} \\sin\\left({\\Theta_2}\\right) + 2 \\, {\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) - {\\ell} {\\mathfrak{p}}^{2} \\sin\\left({\\Theta_2}\\right) - 2 \\, {\\left({\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) + 2 \\, {\\ell} \\sin\\left({\\Theta_2}\\right)\\right)} n^{2} + 4 \\, {\\ell} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}\\right)} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right) + \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(4 \\, {\\left(2 \\, C_{1} {\\ell}^{2} n^{2} + 4 \\, C_{1} {\\ell}^{2} n + 2 \\, C_{1} {\\ell}^{2} + 3 \\, {\\left({\\ell}^{4} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{4} \\sin\\left({\\Theta_2}\\right)\\right)} r\\right)} {r_H}^{3} + 2 \\, {\\left(2 \\, C_{1} n^{2} + 4 \\, C_{1} n + 3 \\, {\\left({\\ell}^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} r + 2 \\, C_{1}\\right)} {r_H} + {\\left(n^{2} {\\mathfrak{q}}^{2} \\sin\\left({\\Theta_2}\\right) + 2 \\, {\\ell}^{2} m \\sin\\left({\\Theta_2}\\right) - {\\left(2 \\, {\\ell}^{2} m \\sin\\left({\\Theta_2}\\right) + \\sin\\left({\\Theta_2}\\right)\\right)} n^{2} + 3 \\, {\\left({\\ell}^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}^{2} - {\\mathfrak{p}}^{2} \\sin\\left({\\Theta_2}\\right) + \\sin\\left({\\Theta_2}\\right)\\right)} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right)\\right)}$$"
],
"text/plain": [
"-2*(3*(l^3*n^2*sin(Th2) - l^3*sin(Th2))*rH^3 - (l*n^2*qf^2*sin(Th2) + 2*l^3*m*sin(Th2) - l*pf^2*sin(Th2) - 2*(l^3*m*sin(Th2) + 2*l*sin(Th2))*n^2 + 4*l*sin(Th2))*rH)*arctan(l*r/sqrt(l^2*rH^2 + 1)) + sqrt(l^2*rH^2 + 1)*(4*(2*C_1*l^2*n^2 + 4*C_1*l^2*n + 2*C_1*l^2 + 3*(l^4*n^2*sin(Th2) - l^4*sin(Th2))*r)*rH^3 + 2*(2*C_1*n^2 + 4*C_1*n + 3*(l^2*n^2*sin(Th2) - l^2*sin(Th2))*r + 2*C_1)*rH + (n^2*qf^2*sin(Th2) + 2*l^2*m*sin(Th2) - (2*l^2*m*sin(Th2) + sin(Th2))*n^2 + 3*(l^2*n^2*sin(Th2) - l^2*sin(Th2))*rH^2 - pf^2*sin(Th2) + sin(Th2))*log((r + rH)/(r - rH)))"
]
},
"execution_count": 93,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y_sol(r).numerator().simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 94,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}4 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(n + 1\\right)}^{2} {r_H}$$"
],
"text/plain": [
"4*(l^2*r^4 + r^2 - 2*m)*(2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)*(n + 1)^2*rH"
]
},
"execution_count": 94,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y_sol(r).denominator().factor()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us check that `Y_sol` is indeed a solution of the differential equation for $\\Upsilon$:"
]
},
{
"cell_type": "code",
"execution_count": 95,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}0 = 0$$"
],
"text/plain": [
"0 == 0"
]
},
"execution_count": 95,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"eq_Y.substitute_function(Y, Y_sol).subs({rH: rH_m}).simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 96,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1/4*(2*(3*(l^3*n^2*sin(Th2) - l^3*sin(Th2))*rH^3 - (l*n^2*qf^2*sin(Th2) + 2*l^3*m*sin(Th2) - l*pf^2*sin(Th2) - 2*(l^3*m*sin(Th2) + 2*l*sin(Th2))*n^2 + 4*l*sin(Th2))*rH)*arctan(l*r/sqrt(l^2*rH^2 + 1)) - sqrt(l^2*rH^2 + 1)*(4*(2*C_1*l^2*n^2 + 4*C_1*l^2*n + 2*C_1*l^2 + 3*(l^4*n^2*sin(Th2) - l^4*sin(Th2))*r)*rH^3 + 2*(2*C_1*n^2 + 4*C_1*n + 3*(l^2*n^2*sin(Th2) - l^2*sin(Th2))*r + 2*C_1)*rH + (n^2*qf^2*sin(Th2) + 2*l^2*m*sin(Th2) - (2*l^2*m*sin(Th2) + sin(Th2))*n^2 + 3*(l^2*n^2*sin(Th2) - l^2*sin(Th2))*rH^2 - pf^2*sin(Th2) + sin(Th2))*log((r + rH)/(r - rH))))/(sqrt(l^2*rH^2 + 1)*(2*(2*l^2*m*n^2 - (l^4*n^2 + 2*l^4*n + l^4)*r^4 + 4*l^2*m*n + 2*l^2*m - (l^2*n^2 + 2*l^2*n + l^2)*r^2)*rH^3 - ((l^2*n^2 + 2*l^2*n + l^2)*r^4 - 2*m*n^2 + (n^2 + 2*n + 1)*r^2 - 4*m*n - 2*m)*rH))\n"
]
}
],
"source": [
"print(Y_sol(r))"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Check of Eq. (4.10) (expression of $\\theta'_1 = \\Upsilon$)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The term involving the constant $C_1$ agrees with that of Eq. (4.10):"
]
},
{
"cell_type": "code",
"execution_count": 97,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{1}{{\\ell}^{2} r^{4} + r^{2} - 2 \\, m}$$"
],
"text/plain": [
"1/(l^2*r^4 + r^2 - 2*m)"
]
},
"execution_count": 97,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s = Y_sol(r).coefficient(C_1).simplify_full()\n",
"s"
]
},
{
"cell_type": "code",
"execution_count": 98,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\mathrm{True}$$"
],
"text/plain": [
"True"
]
},
"execution_count": 98,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"fr4 = l^2*r^4 + r^2 - 2*m\n",
"bool(s == 1/fr4)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us remove it from $\\Upsilon$ and divide the result by $\\sin(2\\Theta_0)$:"
]
},
{
"cell_type": "code",
"execution_count": 99,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{2 \\, {\\left(3 \\, {\\left({\\ell}^{3} n^{2} - {\\ell}^{3}\\right)} {r_H}^{3} - {\\left({\\ell} n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{3} m - 2 \\, {\\left({\\ell}^{3} m + 2 \\, {\\ell}\\right)} n^{2} - {\\ell} {\\mathfrak{p}}^{2} + 4 \\, {\\ell}\\right)} {r_H}\\right)} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right) - {\\left(12 \\, {\\left({\\ell}^{4} n^{2} - {\\ell}^{4}\\right)} r {r_H}^{3} + 6 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} r {r_H} + {\\left(n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{2} m - {\\left(2 \\, {\\ell}^{2} m + 1\\right)} n^{2} + 3 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} {r_H}^{2} - {\\mathfrak{p}}^{2} + 1\\right)} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right)\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}{4 \\, \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(2 \\, {\\left(2 \\, {\\ell}^{2} m n^{2} - {\\left({\\ell}^{4} n^{2} + 2 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{4} + 4 \\, {\\ell}^{2} m n + 2 \\, {\\ell}^{2} m - {\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{2}\\right)} {r_H}^{3} - {\\left({\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{4} - 2 \\, m n^{2} + {\\left(n^{2} + 2 \\, n + 1\\right)} r^{2} - 4 \\, m n - 2 \\, m\\right)} {r_H}\\right)}}$$"
],
"text/plain": [
"1/4*(2*(3*(l^3*n^2 - l^3)*rH^3 - (l*n^2*qf^2 + 2*l^3*m - 2*(l^3*m + 2*l)*n^2 - l*pf^2 + 4*l)*rH)*arctan(l*r/sqrt(l^2*rH^2 + 1)) - (12*(l^4*n^2 - l^4)*r*rH^3 + 6*(l^2*n^2 - l^2)*r*rH + (n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 + 3*(l^2*n^2 - l^2)*rH^2 - pf^2 + 1)*log((r + rH)/(r - rH)))*sqrt(l^2*rH^2 + 1))/(sqrt(l^2*rH^2 + 1)*(2*(2*l^2*m*n^2 - (l^4*n^2 + 2*l^4*n + l^4)*r^4 + 4*l^2*m*n + 2*l^2*m - (l^2*n^2 + 2*l^2*n + l^2)*r^2)*rH^3 - ((l^2*n^2 + 2*l^2*n + l^2)*r^4 - 2*m*n^2 + (n^2 + 2*n + 1)*r^2 - 4*m*n - 2*m)*rH))"
]
},
"execution_count": 99,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y1 = ((Y_sol(r) - s*C_1)/sin(Th2)).simplify_full()\n",
"Y1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The coefficient of the arctan term is"
]
},
{
"cell_type": "code",
"execution_count": 100,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{{\\left(3 \\, {\\ell}^{2} n^{2} {r_H}^{2} + 2 \\, {\\ell}^{2} m n^{2} - n^{2} {\\mathfrak{q}}^{2} - 3 \\, {\\ell}^{2} {r_H}^{2} - 2 \\, {\\ell}^{2} m + 4 \\, n^{2} + {\\mathfrak{p}}^{2} - 4\\right)} {\\ell}}{2 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(n + 1\\right)}^{2}}$$"
],
"text/plain": [
"-1/2*(3*l^2*n^2*rH^2 + 2*l^2*m*n^2 - n^2*qf^2 - 3*l^2*rH^2 - 2*l^2*m + 4*n^2 + pf^2 - 4)*l/((l^2*r^4 + r^2 - 2*m)*(2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)*(n + 1)^2)"
]
},
"execution_count": 100,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s = Y1.coefficient(arctan(l*r/sqrt(l^2*rH^2 + 1))).simplify_full().factor()\n",
"s"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The numerator of this term agrees with Eq. (4.10):"
]
},
{
"cell_type": "code",
"execution_count": 101,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-{\\left({\\ell}^{4} n^{2} {r_H}^{4} - {\\ell}^{4} {r_H}^{4} + 4 \\, {\\ell}^{2} n^{2} {r_H}^{2} - n^{2} {\\mathfrak{q}}^{2} - 4 \\, {\\ell}^{2} {r_H}^{2} + 4 \\, n^{2} + {\\mathfrak{p}}^{2} - 4\\right)} {\\ell}$$"
],
"text/plain": [
"-(l^4*n^2*rH^4 - l^4*rH^4 + 4*l^2*n^2*rH^2 - n^2*qf^2 - 4*l^2*rH^2 + 4*n^2 + pf^2 - 4)*l"
]
},
"execution_count": 101,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s.numerator().subs({m: m_rH}).factor()"
]
},
{
"cell_type": "code",
"execution_count": 102,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\mathrm{True}$$"
],
"text/plain": [
"True"
]
},
"execution_count": 102,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"bool(s.numerator().subs({m: m_rH}) \n",
" == l*((1 - n^2)*(l^2*rH^2 + 2)^2 - pf^2 + n^2*qf^2))"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The denominator agrees with Eq. (4.10) as well:"
]
},
{
"cell_type": "code",
"execution_count": 103,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}2 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(n + 1\\right)}^{2}$$"
],
"text/plain": [
"2*(l^2*r^4 + r^2 - 2*m)*(2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)*(n + 1)^2"
]
},
"execution_count": 103,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s.denominator()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us remove the arctan term from $\\Upsilon$:"
]
},
{
"cell_type": "code",
"execution_count": 104,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{12 \\, {\\left({\\ell}^{4} n^{2} - {\\ell}^{4}\\right)} r {r_H}^{3} + 6 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} r {r_H} + {\\left(n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{2} m - {\\left(2 \\, {\\ell}^{2} m + 1\\right)} n^{2} + 3 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} {r_H}^{2} - {\\mathfrak{p}}^{2} + 1\\right)} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right)}{4 \\, {\\left(2 \\, {\\left(2 \\, {\\ell}^{2} m n^{2} - {\\left({\\ell}^{4} n^{2} + 2 \\, {\\ell}^{4} n + {\\ell}^{4}\\right)} r^{4} + 4 \\, {\\ell}^{2} m n + 2 \\, {\\ell}^{2} m - {\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{2}\\right)} {r_H}^{3} - {\\left({\\left({\\ell}^{2} n^{2} + 2 \\, {\\ell}^{2} n + {\\ell}^{2}\\right)} r^{4} - 2 \\, m n^{2} + {\\left(n^{2} + 2 \\, n + 1\\right)} r^{2} - 4 \\, m n - 2 \\, m\\right)} {r_H}\\right)}}$$"
],
"text/plain": [
"-1/4*(12*(l^4*n^2 - l^4)*r*rH^3 + 6*(l^2*n^2 - l^2)*r*rH + (n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 + 3*(l^2*n^2 - l^2)*rH^2 - pf^2 + 1)*log((r + rH)/(r - rH)))/(2*(2*l^2*m*n^2 - (l^4*n^2 + 2*l^4*n + l^4)*r^4 + 4*l^2*m*n + 2*l^2*m - (l^2*n^2 + 2*l^2*n + l^2)*r^2)*rH^3 - ((l^2*n^2 + 2*l^2*n + l^2)*r^4 - 2*m*n^2 + (n^2 + 2*n + 1)*r^2 - 4*m*n - 2*m)*rH)"
]
},
"execution_count": 104,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y2 = (Y1 - s*arctan(l*r/sqrt(l^2*rH^2 + 1))).simplify_full()\n",
"Y2"
]
},
{
"cell_type": "code",
"execution_count": 105,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}12 \\, {\\left({\\ell}^{4} n^{2} - {\\ell}^{4}\\right)} r {r_H}^{3} + 6 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} r {r_H} + {\\left(n^{2} {\\mathfrak{q}}^{2} + 2 \\, {\\ell}^{2} m - {\\left(2 \\, {\\ell}^{2} m + 1\\right)} n^{2} + 3 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} {r_H}^{2} - {\\mathfrak{p}}^{2} + 1\\right)} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right)$$"
],
"text/plain": [
"12*(l^4*n^2 - l^4)*r*rH^3 + 6*(l^2*n^2 - l^2)*r*rH + (n^2*qf^2 + 2*l^2*m - (2*l^2*m + 1)*n^2 + 3*(l^2*n^2 - l^2)*rH^2 - pf^2 + 1)*log((r + rH)/(r - rH))"
]
},
"execution_count": 105,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y2.numerator().simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 106,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}4 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} {\\left(n + 1\\right)}^{2} {r_H}$$"
],
"text/plain": [
"4*(l^2*r^4 + r^2 - 2*m)*(2*l^2*rH^2 + 1)*(n + 1)^2*rH"
]
},
"execution_count": 106,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y2.denominator().factor()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The coefficient of the log term is"
]
},
{
"cell_type": "code",
"execution_count": 107,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{3 \\, {\\ell}^{2} n^{2} {r_H}^{2} - 2 \\, {\\ell}^{2} m n^{2} + n^{2} {\\mathfrak{q}}^{2} - 3 \\, {\\ell}^{2} {r_H}^{2} + 2 \\, {\\ell}^{2} m - n^{2} - {\\mathfrak{p}}^{2} + 1}{4 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} {\\left(n + 1\\right)}^{2} {r_H}}$$"
],
"text/plain": [
"1/4*(3*l^2*n^2*rH^2 - 2*l^2*m*n^2 + n^2*qf^2 - 3*l^2*rH^2 + 2*l^2*m - n^2 - pf^2 + 1)/((l^2*r^4 + r^2 - 2*m)*(2*l^2*rH^2 + 1)*(n + 1)^2*rH)"
]
},
"execution_count": 107,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s = Y2.coefficient(log((r + rH)/(r - rH))).simplify_full().factor()\n",
"s"
]
},
{
"cell_type": "code",
"execution_count": 108,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-{\\ell}^{4} n^{2} {r_H}^{4} + {\\ell}^{4} {r_H}^{4} + 2 \\, {\\ell}^{2} n^{2} {r_H}^{2} + n^{2} {\\mathfrak{q}}^{2} - 2 \\, {\\ell}^{2} {r_H}^{2} - n^{2} - {\\mathfrak{p}}^{2} + 1$$"
],
"text/plain": [
"-l^4*n^2*rH^4 + l^4*rH^4 + 2*l^2*n^2*rH^2 + n^2*qf^2 - 2*l^2*rH^2 - n^2 - pf^2 + 1"
]
},
"execution_count": 108,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s.numerator().subs({m: m_rH}).factor()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Check against Eq. (4.10):"
]
},
{
"cell_type": "code",
"execution_count": 109,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\mathrm{True}$$"
],
"text/plain": [
"True"
]
},
"execution_count": 109,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"bool(s.numerator().subs({m: m_rH}) == (1 - n^2)*(l^2*rH^2 - 1)^2 - pf^2 + n^2*qf^2)"
]
},
{
"cell_type": "code",
"execution_count": 110,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}4 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} {\\left(n + 1\\right)}^{2} {r_H}$$"
],
"text/plain": [
"4*(l^2*r^4 + r^2 - 2*m)*(2*l^2*rH^2 + 1)*(n + 1)^2*rH"
]
},
"execution_count": 110,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s.denominator()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Given that \n",
"$$ \\mathrm{artanh}\\, x = \\frac{1}{2} \\ln\\left( \\frac{1 + x}{1 - x} \\right) $$\n",
"we have\n",
"$$\n",
" \\ln \\left( \\frac{x + 1}{x - 1} \\right) = 2\\, \\mathrm{artanh}\\left(\\frac{1}{x}\\right)\n",
"$$"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Hence the term in $\\ln\\left(\\frac{r + r_H}{r - r_H}\\right)$ agrees with the corresponding term in Eq. (4.10)."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Finally, the last term in $\\Upsilon$ is"
]
},
{
"cell_type": "code",
"execution_count": 111,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{3 \\, {\\ell}^{2} {\\left(n - 1\\right)} r}{2 \\, {\\left({\\ell}^{2} r^{4} + r^{2} - 2 \\, m\\right)} {\\left(n + 1\\right)}}$$"
],
"text/plain": [
"3/2*l^2*(n - 1)*r/((l^2*r^4 + r^2 - 2*m)*(n + 1))"
]
},
"execution_count": 111,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"Y3 = (Y2 - s*log((r + rH)/(r - rH))).simplify_full()\n",
"Y3.factor()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"This term agrees with Eq. (4.10), given the simplification \n",
"$\\frac{1 - n^2}{(1 + n)^2} = -\\frac{n - 1}{n + 1}$."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"**Conclusion:** we have full agreement with Eq. (4.10)."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Conjugate momenta"
]
},
{
"cell_type": "code",
"execution_count": 112,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
"def conjugate_momenta(lagr, qs, var):\n",
" r\"\"\"\n",
" Compute the conjugate momenta from a given Lagrangian.\n",
"\n",
" INPUT:\n",
"\n",
" - ``lagr`` -- symbolic expression representing the Lagrangian density\n",
" - ``qs`` -- either a single symbolic function or a list/tuple of\n",
" symbolic functions, representing the `q`'s; these functions must\n",
" appear in ``lagr`` up to at most their first derivatives\n",
" - ``var`` -- either a single variable, typically `t` (1-dimensional\n",
" problem) or a list/tuple of symbolic variables; in the latter case the\n",
" time coordinate must the first one\n",
"\n",
" OUTPUT:\n",
"\n",
" - list of conjugate momenta; if only one function is involved, the\n",
" single conjugate momentum is returned instead.\n",
"\n",
" \"\"\"\n",
" if not isinstance(qs, (list, tuple)):\n",
" qs = [qs]\n",
" if not isinstance(var, (list, tuple)):\n",
" var = [var]\n",
" n = len(qs)\n",
" d = len(var)\n",
" dqvt = [SR.var('qxxxx{}_t'.format(q)) for q in qs]\n",
" subs = {diff(qs[i](*var), var[0]): dqvt[i] for i in range(n)}\n",
" subs_inv = {dqvt[i]: diff(qs[i](*var), var[0]) for i in range(n)}\n",
" lg = lagr.substitute(subs)\n",
" ps = [diff(lg, dotq).simplify_full().substitute(subs_inv) for dotq in dqvt]\n",
" if n == 1:\n",
" return ps[0]\n",
" return ps"
]
},
{
"cell_type": "code",
"execution_count": 113,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\left[-{\\left({\\mu_0}^{2} - 1\\right)} a^{2} {\\ell}^{2} r^{4} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right) - {\\left({\\mu_0}^{2} - 1\\right)} a^{2} r^{2} \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right) + 2 \\, {\\left({\\mu_0}^{2} - 1\\right)} a^{2} m \\frac{\\partial}{\\partial r}\\phi_{1}\\left(r\\right), {\\mu_0}^{2} a^{2} {\\ell}^{2} n^{2} r^{4} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right) + {\\mu_0}^{2} a^{2} n^{2} r^{2} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right) - 2 \\, {\\mu_0}^{2} a^{2} m n^{2} \\frac{\\partial}{\\partial r}\\psi_{1}\\left(r\\right)\\right]$$"
],
"text/plain": [
"[-(Mu0^2 - 1)*a^2*l^2*r^4*diff(phi_1(r), r) - (Mu0^2 - 1)*a^2*r^2*diff(phi_1(r), r) + 2*(Mu0^2 - 1)*a^2*m*diff(phi_1(r), r),\n",
" Mu0^2*a^2*l^2*n^2*r^4*diff(psi_1(r), r) + Mu0^2*a^2*n^2*r^2*diff(psi_1(r), r) - 2*Mu0^2*a^2*m*n^2*diff(psi_1(r), r)]"
]
},
"execution_count": 113,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"pis = conjugate_momenta(L_a2, [phi_1, psi_1], r)\n",
"pis"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Check of Eq. (4.15):"
]
},
{
"cell_type": "code",
"execution_count": 114,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-{\\left({\\mu_0}^{2} - 1\\right)} a {\\mathfrak{p}}$$"
],
"text/plain": [
"-(Mu0^2 - 1)*a*pf"
]
},
"execution_count": 114,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"pi_phi_r = (pis[0]/a).substitute_function(phi_1, phi1_sol).simplify_full()\n",
"pi_phi_r"
]
},
{
"cell_type": "code",
"execution_count": 115,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}{\\mu_0}^{2} a n^{2} {\\mathfrak{q}}$$"
],
"text/plain": [
"Mu0^2*a*n^2*qf"
]
},
"execution_count": 115,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"pi_psi_r = (pis[1]/a).substitute_function(psi_1, psi1_sol).simplify_full()\n",
"pi_psi_r"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"### Check of Eq. (4.14):"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We start from $\\pi^r_\\theta$ as given by Eq. (4.13):"
]
},
{
"cell_type": "code",
"execution_count": 116,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{2 \\, {\\left(3 \\, {\\left(a^{2} {\\ell}^{3} n^{2} \\sin\\left({\\Theta_2}\\right) - a^{2} {\\ell}^{3} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}^{3} - {\\left(a^{2} {\\ell} n^{2} {\\mathfrak{q}}^{2} \\sin\\left({\\Theta_2}\\right) + 2 \\, a^{2} {\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) - a^{2} {\\ell} {\\mathfrak{p}}^{2} \\sin\\left({\\Theta_2}\\right) + 4 \\, a^{2} {\\ell} \\sin\\left({\\Theta_2}\\right) - 2 \\, {\\left(a^{2} {\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) + 2 \\, a^{2} {\\ell} \\sin\\left({\\Theta_2}\\right)\\right)} n^{2}\\right)} {r_H}\\right)} \\arctan\\left(\\frac{{\\ell} r}{\\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}\\right) - \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(4 \\, {\\left(2 \\, C_{1} a^{2} {\\ell}^{2} n^{2} + 4 \\, C_{1} a^{2} {\\ell}^{2} n + 2 \\, C_{1} a^{2} {\\ell}^{2} + 3 \\, {\\left(a^{2} {\\ell}^{4} n^{2} \\sin\\left({\\Theta_2}\\right) - a^{2} {\\ell}^{4} \\sin\\left({\\Theta_2}\\right)\\right)} r\\right)} {r_H}^{3} + 2 \\, {\\left(2 \\, C_{1} a^{2} n^{2} + 4 \\, C_{1} a^{2} n + 2 \\, C_{1} a^{2} + 3 \\, {\\left(a^{2} {\\ell}^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - a^{2} {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} r\\right)} {r_H} + {\\left(a^{2} n^{2} {\\mathfrak{q}}^{2} \\sin\\left({\\Theta_2}\\right) + 2 \\, a^{2} {\\ell}^{2} m \\sin\\left({\\Theta_2}\\right) - a^{2} {\\mathfrak{p}}^{2} \\sin\\left({\\Theta_2}\\right) - {\\left(2 \\, a^{2} {\\ell}^{2} m \\sin\\left({\\Theta_2}\\right) + a^{2} \\sin\\left({\\Theta_2}\\right)\\right)} n^{2} + 3 \\, {\\left(a^{2} {\\ell}^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - a^{2} {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}^{2} + a^{2} \\sin\\left({\\Theta_2}\\right)\\right)} \\log\\left(\\frac{r + {r_H}}{r - {r_H}}\\right)\\right)}}{4 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{3} + {r_H}\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}$$"
],
"text/plain": [
"-1/4*(2*(3*(a^2*l^3*n^2*sin(Th2) - a^2*l^3*sin(Th2))*rH^3 - (a^2*l*n^2*qf^2*sin(Th2) + 2*a^2*l^3*m*sin(Th2) - a^2*l*pf^2*sin(Th2) + 4*a^2*l*sin(Th2) - 2*(a^2*l^3*m*sin(Th2) + 2*a^2*l*sin(Th2))*n^2)*rH)*arctan(l*r/sqrt(l^2*rH^2 + 1)) - sqrt(l^2*rH^2 + 1)*(4*(2*C_1*a^2*l^2*n^2 + 4*C_1*a^2*l^2*n + 2*C_1*a^2*l^2 + 3*(a^2*l^4*n^2*sin(Th2) - a^2*l^4*sin(Th2))*r)*rH^3 + 2*(2*C_1*a^2*n^2 + 4*C_1*a^2*n + 2*C_1*a^2 + 3*(a^2*l^2*n^2*sin(Th2) - a^2*l^2*sin(Th2))*r)*rH + (a^2*n^2*qf^2*sin(Th2) + 2*a^2*l^2*m*sin(Th2) - a^2*pf^2*sin(Th2) - (2*a^2*l^2*m*sin(Th2) + a^2*sin(Th2))*n^2 + 3*(a^2*l^2*n^2*sin(Th2) - a^2*l^2*sin(Th2))*rH^2 + a^2*sin(Th2))*log((r + rH)/(r - rH))))/((2*l^2*rH^3 + rH)*sqrt(l^2*rH^2 + 1))"
]
},
"execution_count": 116,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"pi_theta = (fr4*(a + b)^2*Y_sol(r)).simplify_full()\n",
"pi_theta "
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let us perform an expansion in $1/r$ for $r\\rightarrow +\\infty$:"
]
},
{
"cell_type": "code",
"execution_count": 117,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{3}{2} \\, {\\left(a^{2} {\\ell}^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - a^{2} {\\ell}^{2} \\sin\\left({\\Theta_2}\\right)\\right)} r + \\frac{3 \\, {\\left(a^{2} n^{2} \\sin\\left({\\Theta_2}\\right) - a^{2} \\sin\\left({\\Theta_2}\\right)\\right)}}{2 \\, r} + \\frac{\\pi a^{2} {\\ell} n^{2} {\\mathfrak{q}}^{2} \\sin\\left({\\Theta_2}\\right) + 2 \\, \\pi a^{2} {\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) - \\pi a^{2} {\\ell} {\\mathfrak{p}}^{2} \\sin\\left({\\Theta_2}\\right) + 4 \\, \\pi a^{2} {\\ell} \\sin\\left({\\Theta_2}\\right) - 2 \\, {\\left(\\pi a^{2} {\\ell}^{3} m \\sin\\left({\\Theta_2}\\right) + 2 \\, \\pi a^{2} {\\ell} \\sin\\left({\\Theta_2}\\right)\\right)} n^{2} - 3 \\, {\\left(\\pi a^{2} {\\ell}^{3} n^{2} \\sin\\left({\\Theta_2}\\right) - \\pi a^{2} {\\ell}^{3} \\sin\\left({\\Theta_2}\\right)\\right)} {r_H}^{2} + 4 \\, {\\left(C_{1} a^{2} n^{2} + 2 \\, C_{1} a^{2} n + C_{1} a^{2} + 2 \\, {\\left(C_{1} a^{2} {\\ell}^{2} n^{2} + 2 \\, C_{1} a^{2} {\\ell}^{2} n + C_{1} a^{2} {\\ell}^{2}\\right)} {r_H}^{2}\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}{4 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}$$"
],
"text/plain": [
"3/2*(a^2*l^2*n^2*sin(Th2) - a^2*l^2*sin(Th2))*r + 3/2*(a^2*n^2*sin(Th2) - a^2*sin(Th2))/r + 1/4*(pi*a^2*l*n^2*qf^2*sin(Th2) + 2*pi*a^2*l^3*m*sin(Th2) - pi*a^2*l*pf^2*sin(Th2) + 4*pi*a^2*l*sin(Th2) - 2*(pi*a^2*l^3*m*sin(Th2) + 2*pi*a^2*l*sin(Th2))*n^2 - 3*(pi*a^2*l^3*n^2*sin(Th2) - pi*a^2*l^3*sin(Th2))*rH^2 + 4*(C_1*a^2*n^2 + 2*C_1*a^2*n + C_1*a^2 + 2*(C_1*a^2*l^2*n^2 + 2*C_1*a^2*l^2*n + C_1*a^2*l^2)*rH^2)*sqrt(l^2*rH^2 + 1))/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1))"
]
},
"execution_count": 117,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"assume(l > 0)\n",
"\n",
"u = var('u')\n",
"assume(u > 0)\n",
"s = pi_theta.subs({r: 1/u}).simplify_log()\n",
"s = s.taylor(u, 0, 2)\n",
"s = s.subs({u: 1/r})\n",
"s"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We consider $\\frac{\\pi^r_\\theta}{(a^2/2)\\sin(2\\Theta_0)}$:"
]
},
{
"cell_type": "code",
"execution_count": 118,
"metadata": {
"collapsed": false,
"scrolled": true
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{3 \\, \\pi {\\ell}^{3} n^{2} {r_H}^{2}}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} - \\frac{\\pi {\\ell}^{3} m n^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} + 3 \\, {\\ell}^{2} n^{2} r + \\frac{4 \\, C_{1} {\\ell}^{2} n^{2} {r_H}^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{\\pi {\\ell} n^{2} {\\mathfrak{q}}^{2}}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} + \\frac{3 \\, \\pi {\\ell}^{3} {r_H}^{2}}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} + \\frac{8 \\, C_{1} {\\ell}^{2} n {r_H}^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{\\pi {\\ell}^{3} m}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} - 3 \\, {\\ell}^{2} r + \\frac{4 \\, C_{1} {\\ell}^{2} {r_H}^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} - \\frac{2 \\, \\pi {\\ell} n^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} - \\frac{\\pi {\\ell} {\\mathfrak{p}}^{2}}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} + \\frac{3 \\, n^{2}}{r} + \\frac{2 \\, C_{1} n^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{2 \\, \\pi {\\ell}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}} + \\frac{4 \\, C_{1} n}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} - \\frac{3}{r} + \\frac{2 \\, C_{1}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)}$$"
],
"text/plain": [
"-3/2*pi*l^3*n^2*rH^2/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) - pi*l^3*m*n^2/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) + 3*l^2*n^2*r + 4*C_1*l^2*n^2*rH^2/((2*l^2*rH^2 + 1)*sin(Th2)) + 1/2*pi*l*n^2*qf^2/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) + 3/2*pi*l^3*rH^2/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) + 8*C_1*l^2*n*rH^2/((2*l^2*rH^2 + 1)*sin(Th2)) + pi*l^3*m/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) - 3*l^2*r + 4*C_1*l^2*rH^2/((2*l^2*rH^2 + 1)*sin(Th2)) - 2*pi*l*n^2/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) - 1/2*pi*l*pf^2/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) + 3*n^2/r + 2*C_1*n^2/((2*l^2*rH^2 + 1)*sin(Th2)) + 2*pi*l/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1)) + 4*C_1*n/((2*l^2*rH^2 + 1)*sin(Th2)) - 3/r + 2*C_1/((2*l^2*rH^2 + 1)*sin(Th2))"
]
},
"execution_count": 118,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s1 = (s/(a^2/2*sin(Th2))).expand()\n",
"s1"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The term in factor of $C_1$ is"
]
},
{
"cell_type": "code",
"execution_count": 119,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{4 \\, {\\ell}^{2} n^{2} {r_H}^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{8 \\, {\\ell}^{2} n {r_H}^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{4 \\, {\\ell}^{2} {r_H}^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{2 \\, n^{2}}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{4 \\, n}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)} + \\frac{2}{{\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sin\\left({\\Theta_2}\\right)}$$"
],
"text/plain": [
"4*l^2*n^2*rH^2/((2*l^2*rH^2 + 1)*sin(Th2)) + 8*l^2*n*rH^2/((2*l^2*rH^2 + 1)*sin(Th2)) + 4*l^2*rH^2/((2*l^2*rH^2 + 1)*sin(Th2)) + 2*n^2/((2*l^2*rH^2 + 1)*sin(Th2)) + 4*n/((2*l^2*rH^2 + 1)*sin(Th2)) + 2/((2*l^2*rH^2 + 1)*sin(Th2))"
]
},
"execution_count": 119,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s1.coefficient(C_1)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"It is a constant term, of the type $\\tilde{C}_1/\\sin(2\\Theta_0)$, in agreement with Eq. (4.14).\n",
"We remove it from the main term:"
]
},
{
"cell_type": "code",
"execution_count": 120,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{12 \\, {\\left({\\ell}^{4} n^{2} - {\\ell}^{4} + {\\left({\\ell}^{6} n^{2} - {\\ell}^{6}\\right)} r^{2}\\right)} {r_H}^{4} + 6 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} r^{2} + 18 \\, {\\left({\\ell}^{2} n^{2} + {\\left({\\ell}^{4} n^{2} - {\\ell}^{4}\\right)} r^{2} - {\\ell}^{2}\\right)} {r_H}^{2} + 6 \\, n^{2} - \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(3 \\, {\\left(\\pi {\\ell}^{3} n^{2} - \\pi {\\ell}^{3}\\right)} r {r_H}^{2} - {\\left(\\pi {\\ell} n^{2} {\\mathfrak{q}}^{2} + 2 \\, \\pi {\\ell}^{3} m - \\pi {\\ell} {\\mathfrak{p}}^{2} - 2 \\, {\\left(\\pi {\\ell}^{3} m + 2 \\, \\pi {\\ell}\\right)} n^{2} + 4 \\, \\pi {\\ell}\\right)} r\\right)} - 6}{2 \\, {\\left(2 \\, {\\ell}^{4} r {r_H}^{4} + 3 \\, {\\ell}^{2} r {r_H}^{2} + r\\right)}}$$"
],
"text/plain": [
"1/2*(12*(l^4*n^2 - l^4 + (l^6*n^2 - l^6)*r^2)*rH^4 + 6*(l^2*n^2 - l^2)*r^2 + 18*(l^2*n^2 + (l^4*n^2 - l^4)*r^2 - l^2)*rH^2 + 6*n^2 - sqrt(l^2*rH^2 + 1)*(3*(pi*l^3*n^2 - pi*l^3)*r*rH^2 - (pi*l*n^2*qf^2 + 2*pi*l^3*m - pi*l*pf^2 - 2*(pi*l^3*m + 2*pi*l)*n^2 + 4*pi*l)*r) - 6)/(2*l^4*r*rH^4 + 3*l^2*r*rH^2 + r)"
]
},
"execution_count": 120,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2 = (s1 - s1.coefficient(C_1)*C_1).simplify_full()\n",
"s2"
]
},
{
"cell_type": "code",
"execution_count": 121,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}12 \\, {\\left({\\ell}^{4} n^{2} - {\\ell}^{4} + {\\left({\\ell}^{6} n^{2} - {\\ell}^{6}\\right)} r^{2}\\right)} {r_H}^{4} + 6 \\, {\\left({\\ell}^{2} n^{2} - {\\ell}^{2}\\right)} r^{2} + 18 \\, {\\left({\\ell}^{2} n^{2} + {\\left({\\ell}^{4} n^{2} - {\\ell}^{4}\\right)} r^{2} - {\\ell}^{2}\\right)} {r_H}^{2} + 6 \\, n^{2} - \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\left(3 \\, {\\left(\\pi {\\ell}^{3} n^{2} - \\pi {\\ell}^{3}\\right)} r {r_H}^{2} - {\\left(\\pi {\\ell} n^{2} {\\mathfrak{q}}^{2} + 2 \\, \\pi {\\ell}^{3} m - \\pi {\\ell} {\\mathfrak{p}}^{2} - 2 \\, {\\left(\\pi {\\ell}^{3} m + 2 \\, \\pi {\\ell}\\right)} n^{2} + 4 \\, \\pi {\\ell}\\right)} r\\right)} - 6$$"
],
"text/plain": [
"12*(l^4*n^2 - l^4 + (l^6*n^2 - l^6)*r^2)*rH^4 + 6*(l^2*n^2 - l^2)*r^2 + 18*(l^2*n^2 + (l^4*n^2 - l^4)*r^2 - l^2)*rH^2 + 6*n^2 - sqrt(l^2*rH^2 + 1)*(3*(pi*l^3*n^2 - pi*l^3)*r*rH^2 - (pi*l*n^2*qf^2 + 2*pi*l^3*m - pi*l*pf^2 - 2*(pi*l^3*m + 2*pi*l)*n^2 + 4*pi*l)*r) - 6"
]
},
"execution_count": 121,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2.numerator().simplify_full()"
]
},
{
"cell_type": "code",
"execution_count": 122,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} {\\left({\\ell}^{2} {r_H}^{2} + 1\\right)} r$$"
],
"text/plain": [
"2*(2*l^2*rH^2 + 1)*(l^2*rH^2 + 1)*r"
]
},
"execution_count": 122,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2.denominator().factor()"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Let divide both the numerator and denominator by $r$:"
]
},
{
"cell_type": "code",
"execution_count": 123,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}12 \\, {\\ell}^{6} n^{2} r {r_H}^{4} - 12 \\, {\\ell}^{6} r {r_H}^{4} + 18 \\, {\\ell}^{4} n^{2} r {r_H}^{2} + \\frac{12 \\, {\\ell}^{4} n^{2} {r_H}^{4}}{r} - 3 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} n^{2} {r_H}^{2} - 2 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} m n^{2} - 18 \\, {\\ell}^{4} r {r_H}^{2} - \\frac{12 \\, {\\ell}^{4} {r_H}^{4}}{r} + \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} n^{2} {\\mathfrak{q}}^{2} + 3 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} {r_H}^{2} + 2 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} m + 6 \\, {\\ell}^{2} n^{2} r + \\frac{18 \\, {\\ell}^{2} n^{2} {r_H}^{2}}{r} - 4 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} n^{2} - \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} {\\mathfrak{p}}^{2} - 6 \\, {\\ell}^{2} r - \\frac{18 \\, {\\ell}^{2} {r_H}^{2}}{r} + 4 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} + \\frac{6 \\, n^{2}}{r} - \\frac{6}{r}$$"
],
"text/plain": [
"12*l^6*n^2*r*rH^4 - 12*l^6*r*rH^4 + 18*l^4*n^2*r*rH^2 + 12*l^4*n^2*rH^4/r - 3*pi*sqrt(l^2*rH^2 + 1)*l^3*n^2*rH^2 - 2*pi*sqrt(l^2*rH^2 + 1)*l^3*m*n^2 - 18*l^4*r*rH^2 - 12*l^4*rH^4/r + pi*sqrt(l^2*rH^2 + 1)*l*n^2*qf^2 + 3*pi*sqrt(l^2*rH^2 + 1)*l^3*rH^2 + 2*pi*sqrt(l^2*rH^2 + 1)*l^3*m + 6*l^2*n^2*r + 18*l^2*n^2*rH^2/r - 4*pi*sqrt(l^2*rH^2 + 1)*l*n^2 - pi*sqrt(l^2*rH^2 + 1)*l*pf^2 - 6*l^2*r - 18*l^2*rH^2/r + 4*pi*sqrt(l^2*rH^2 + 1)*l + 6*n^2/r - 6/r"
]
},
"execution_count": 123,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2n = (s2.numerator()/r).expand()\n",
"s2n"
]
},
{
"cell_type": "code",
"execution_count": 124,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} {\\left({\\ell}^{2} {r_H}^{2} + 1\\right)}$$"
],
"text/plain": [
"2*(2*l^2*rH^2 + 1)*(l^2*rH^2 + 1)"
]
},
"execution_count": 124,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s2d = (s2.denominator()/r).factor()\n",
"s2d"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The coefficient of the term in $r$ is"
]
},
{
"cell_type": "code",
"execution_count": 125,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}3 \\, {\\ell}^{2} {\\left(n + 1\\right)} {\\left(n - 1\\right)}$$"
],
"text/plain": [
"3*l^2*(n + 1)*(n - 1)"
]
},
"execution_count": 125,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s = s2n.coefficient(r).factor()\n",
"s/s2d"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"This is in agreement with Eq. (4.14)."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"We remove it:"
]
},
{
"cell_type": "code",
"execution_count": 126,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\frac{12 \\, {\\ell}^{4} n^{2} {r_H}^{4}}{r} - 3 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} n^{2} {r_H}^{2} - 2 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} m n^{2} - \\frac{12 \\, {\\ell}^{4} {r_H}^{4}}{r} + \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} n^{2} {\\mathfrak{q}}^{2} + 3 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} {r_H}^{2} + 2 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} m + \\frac{18 \\, {\\ell}^{2} n^{2} {r_H}^{2}}{r} - 4 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} n^{2} - \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} {\\mathfrak{p}}^{2} - \\frac{18 \\, {\\ell}^{2} {r_H}^{2}}{r} + 4 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} + \\frac{6 \\, n^{2}}{r} - \\frac{6}{r}$$"
],
"text/plain": [
"12*l^4*n^2*rH^4/r - 3*pi*sqrt(l^2*rH^2 + 1)*l^3*n^2*rH^2 - 2*pi*sqrt(l^2*rH^2 + 1)*l^3*m*n^2 - 12*l^4*rH^4/r + pi*sqrt(l^2*rH^2 + 1)*l*n^2*qf^2 + 3*pi*sqrt(l^2*rH^2 + 1)*l^3*rH^2 + 2*pi*sqrt(l^2*rH^2 + 1)*l^3*m + 18*l^2*n^2*rH^2/r - 4*pi*sqrt(l^2*rH^2 + 1)*l*n^2 - pi*sqrt(l^2*rH^2 + 1)*l*pf^2 - 18*l^2*rH^2/r + 4*pi*sqrt(l^2*rH^2 + 1)*l + 6*n^2/r - 6/r"
]
},
"execution_count": 126,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s3n = (s2n - s*r).simplify_full().expand()\n",
"s3n"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The coefficient of the term in $1/r$ is"
]
},
{
"cell_type": "code",
"execution_count": 127,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}3 \\, {\\left(n + 1\\right)} {\\left(n - 1\\right)}$$"
],
"text/plain": [
"3*(n + 1)*(n - 1)"
]
},
"execution_count": 127,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s = s3n.coefficient(r^(-1)).factor()\n",
"s/s2d"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"This is in agreement with Eq. (4.14)."
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"Finally the remaining term is"
]
},
{
"cell_type": "code",
"execution_count": 128,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-3 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} n^{2} {r_H}^{2} - 2 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} m n^{2} + \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} n^{2} {\\mathfrak{q}}^{2} + 3 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} {r_H}^{2} + 2 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}^{3} m - 4 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} n^{2} - \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell} {\\mathfrak{p}}^{2} + 4 \\, \\pi \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}$$"
],
"text/plain": [
"-3*pi*sqrt(l^2*rH^2 + 1)*l^3*n^2*rH^2 - 2*pi*sqrt(l^2*rH^2 + 1)*l^3*m*n^2 + pi*sqrt(l^2*rH^2 + 1)*l*n^2*qf^2 + 3*pi*sqrt(l^2*rH^2 + 1)*l^3*rH^2 + 2*pi*sqrt(l^2*rH^2 + 1)*l^3*m - 4*pi*sqrt(l^2*rH^2 + 1)*l*n^2 - pi*sqrt(l^2*rH^2 + 1)*l*pf^2 + 4*pi*sqrt(l^2*rH^2 + 1)*l"
]
},
"execution_count": 128,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s4n = (s3n - s/r).simplify_full().expand()\n",
"s4n"
]
},
{
"cell_type": "code",
"execution_count": 129,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\pi {\\left(3 \\, {\\ell}^{2} n^{2} {r_H}^{2} + 2 \\, {\\ell}^{2} m n^{2} - n^{2} {\\mathfrak{q}}^{2} - 3 \\, {\\ell}^{2} {r_H}^{2} - 2 \\, {\\ell}^{2} m + 4 \\, n^{2} + {\\mathfrak{p}}^{2} - 4\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1} {\\ell}$$"
],
"text/plain": [
"-pi*(3*l^2*n^2*rH^2 + 2*l^2*m*n^2 - n^2*qf^2 - 3*l^2*rH^2 - 2*l^2*m + 4*n^2 + pf^2 - 4)*sqrt(l^2*rH^2 + 1)*l"
]
},
"execution_count": 129,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s4n.factor()"
]
},
{
"cell_type": "code",
"execution_count": 130,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}-\\frac{\\pi {\\left({\\ell}^{4} n^{2} {r_H}^{4} - {\\ell}^{4} {r_H}^{4} + 4 \\, {\\ell}^{2} n^{2} {r_H}^{2} - n^{2} {\\mathfrak{q}}^{2} - 4 \\, {\\ell}^{2} {r_H}^{2} + 4 \\, n^{2} + {\\mathfrak{p}}^{2} - 4\\right)} {\\ell}}{2 \\, {\\left(2 \\, {\\ell}^{2} {r_H}^{2} + 1\\right)} \\sqrt{{\\ell}^{2} {r_H}^{2} + 1}}$$"
],
"text/plain": [
"-1/2*pi*(l^4*n^2*rH^4 - l^4*rH^4 + 4*l^2*n^2*rH^2 - n^2*qf^2 - 4*l^2*rH^2 + 4*n^2 + pf^2 - 4)*l/((2*l^2*rH^2 + 1)*sqrt(l^2*rH^2 + 1))"
]
},
"execution_count": 130,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"s = (s4n.factor()/s2d).subs({m: m_rH}).factor()\n",
"s"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"The denominator clearly agrees with Eq. (4.14); the numerator agrees as well:"
]
},
{
"cell_type": "code",
"execution_count": 131,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/html": [
""
],
"text/latex": [
"$$\\newcommand{\\Bold}[1]{\\mathbf{#1}}\\mathrm{True}$$"
],
"text/plain": [
"True"
]
},
"execution_count": 131,
"metadata": {
},
"output_type": "execute_result"
}
],
"source": [
"bool(s.numerator()/(pi*l) == (1 - n^2)*(l^2*rH^2 + 2)^2 - pf^2 + n^2*qf^2)"
]
},
{
"cell_type": "markdown",
"metadata": {
"collapsed": false
},
"source": [
"**Conclusion:** we have full agreement with Eq. (4.14)."
]
},
{
"cell_type": "code",
"execution_count": 0,
"metadata": {
"collapsed": false
},
"outputs": [
],
"source": [
]
}
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