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Ok-landscape
GitHub Repository: Ok-landscape/computational-pipeline
Path: blob/main/notebooks/published/character_theory/character_theory_posts.txt
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# Social Media Posts: Character Theory of Finite Groups
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# Generated from: notebooks/published/character_theory.ipynb
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## SHORT-FORM POSTS
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### TWITTER/X (< 280 chars)
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Character theory distills entire group representations into a single function: χ(g) = Tr(ρ(g)). We computed the character table of S₃ and verified orthogonality. Beautiful math in action!
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#Python #Math #GroupTheory #AbstractAlgebra
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### BLUESKY (< 300 chars)
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Exploring character theory: how traces of representation matrices encode the structure of finite groups. Built the complete character table of S₃ (symmetric group on 3 elements) and verified the orthogonality relations that make characters so powerful.
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#Math #GroupTheory #Python
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### THREADS (< 500 chars)
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Ever wondered how mathematicians compress an entire group representation into a single number?
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Character theory does exactly that! The character χ(g) = Tr(ρ(g)) captures essential info about how groups act on vector spaces.
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We explored S₃ (all permutations of 3 elements) and found:
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- 3 conjugacy classes
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- 3 irreducible representations
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- A beautiful orthonormality relation: ⟨χᵢ, χⱼ⟩ = δᵢⱼ
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The sum of squared degrees equals the group order: 1² + 1² + 2² = 6 = |S₃|
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### MASTODON (< 500 chars)
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Implemented character theory for finite groups in Python!
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Key results for S₃:
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• Characters are class functions: χ(xgx⁻¹) = χ(g)
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• First orthogonality: (1/|G|) Σ χᵢ(g)χⱼ(g)* = δᵢⱼ
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• Three irreducible reps: trivial (dim 1), sign (dim 1), standard (dim 2)
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• Sum of squares: 1² + 1² + 2² = 6 = |S₃| ✓
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The character table is a complete invariant encoding all representation-theoretic information.
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#Math #GroupTheory #RepresentationTheory #Python
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## LONG-FORM POSTS
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### REDDIT (r/learnpython or r/math)
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**Title:** Built a Character Table Calculator for Finite Groups in Python - Here's How Characters Reveal Group Structure
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**Body:**
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I just finished implementing character theory for the symmetric group S₃ and wanted to share what I learned!
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**What is character theory?**
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A character χ of a group representation ρ is simply the trace of the matrix: χ(g) = Tr(ρ(g)). This single number encodes essential information about how the group acts.
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**Why is this cool?**
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1. Characters are *class functions* - they're constant on conjugacy classes (elements related by conjugation)
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2. Irreducible characters form an orthonormal basis with respect to the inner product ⟨χᵢ, χⱼ⟩ = (1/|G|) Σ χᵢ(g)χⱼ(g)*
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3. The number of irreducible representations equals the number of conjugacy classes
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**Results for S₃:**
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S₃ has 6 elements and 3 conjugacy classes:
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- Identity: {e}
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- Transpositions: {(12), (13), (23)}
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- 3-cycles: {(123), (132)}
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The character table:
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| | e | (12) | (123) |
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|--|---|------|-------|
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| χ_trivial | 1 | 1 | 1 |
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| χ_sign | 1 | -1 | 1 |
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| χ_standard | 2 | 0 | -1 |
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The degrees satisfy: 1² + 1² + 2² = 6 = |S₃|
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**Applications:**
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- Molecular symmetry in chemistry
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- Particle physics (classifying bosons/fermions)
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- Generalized Fourier analysis on groups
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Check out the full interactive notebook with code and visualizations:
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https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/character_theory.ipynb
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### FACEBOOK (< 500 chars)
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Just explored one of the most elegant ideas in abstract algebra: character theory!
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The key insight: you can compress an entire group representation (matrices showing how a group acts) into a single function using traces.
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For the symmetric group S₃ (all ways to shuffle 3 objects), we found exactly 3 irreducible representations whose squared dimensions sum to 6 - the group's size!
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Math is beautiful when patterns like this emerge.
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Full notebook: https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/character_theory.ipynb
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### LINKEDIN (< 1000 chars)
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Applying Representation Theory: Building Character Tables with Python
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In my latest computational notebook, I explored character theory - a cornerstone of abstract algebra with applications spanning chemistry, physics, and data science.
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Key Technical Highlights:
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• Implemented group composition and conjugacy class detection algorithms
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• Constructed three irreducible representations of S₃: trivial, sign (parity), and the 2D standard representation
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• Verified orthogonality relations that make character theory computationally tractable
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• Visualized the character table and inner product matrix
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The character table of a finite group is a powerful invariant - it encodes:
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- Normal subgroup structure (kernels of characters)
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- Whether the group is abelian
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- Centralizer sizes via orthogonality
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Skills demonstrated: NumPy for linear algebra, algorithmic thinking for permutation groups, mathematical rigor in verification.
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Character theory underlies techniques in signal processing on graphs, molecular orbital theory, and quantum computing gate synthesis.
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View the interactive notebook: https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/character_theory.ipynb
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#Mathematics #Python #DataScience #ComputationalThinking #AbstractAlgebra
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### INSTAGRAM (< 500 chars)
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Character Theory of Finite Groups ✨
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What you're seeing: The character table of S₃ - a matrix encoding ALL essential information about how this group acts on vector spaces.
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The magic:
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→ 3 conjugacy classes = 3 irreducible representations
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→ 1² + 1² + 2² = 6 (group order!)
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→ Characters form an orthonormal basis
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The right panel shows perfect orthogonality - different characters are perpendicular, same character has length 1.
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Abstract algebra meets Python.
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#math #abstractalgebra #grouptheory #python #dataviz #science #coding
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