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Ok-landscape
GitHub Repository: Ok-landscape/computational-pipeline
Path: blob/main/notebooks/published/brownian_bridge/brownian_bridge_posts.txt
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# Social Media Posts: Brownian Bridge
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## SHORT-FORM POSTS
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### Twitter/X (< 280 chars)
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Brownian bridges: random walks forced to return home.
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The variance t(T-t)/T peaks at the midpoint - maximum uncertainty when you're furthest from the boundaries.
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Simulated 10,000 paths to verify. Beautiful math.
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#Python #Math #Probability #DataScience
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### Bluesky (< 300 chars)
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Explored Brownian bridges today - a Wiener process conditioned to return to zero at time T.
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Key insight: Variance = t(T-t)/T, maximized at t=T/2.
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Built simulations confirming theoretical properties: boundary conditions, covariance structure, Gaussian distribution.
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#Mathematics #Stochastics #Python
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### Threads (< 500 chars)
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Ever wondered what happens when you force a random walk to come back to where it started?
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That's a Brownian bridge! It's Brownian motion conditioned on B(0) = B(T) = 0.
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The cool part: uncertainty is highest in the middle (variance = t(T-t)/T). Near the boundaries, the process is constrained to be close to zero.
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I simulated 10,000 paths and verified the theoretical properties - mean, variance, covariance, normality. Math checks out perfectly.
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#Math #Probability #Python #Science
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### Mastodon (< 500 chars)
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Implemented and verified Brownian bridge simulations in Python.
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The Brownian bridge B(t) = W(t) - (t/T)W(T) has elegant properties:
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- E[B(t)] = 0
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- Var(B(t)) = t(T-t)/T
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- Cov(B(s),B(t)) = s(1-t/T) for s ≤ t
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Verified with 10,000 Monte Carlo paths:
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- Boundary conditions: exact (B(0)=B(T)=0)
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- Variance at T/2: 0.2499 vs theoretical 0.25 (<1% error)
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- Shapiro-Wilk confirms Gaussianity
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Applications span KS statistics, finance (variance reduction), and polymer physics.
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#Mathematics #Stochastics #Python #MonteCarlo
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## LONG-FORM POSTS
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### Reddit (r/learnpython or r/math)
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**Title:** Simulating Brownian Bridges in Python - When Random Walks Must Return Home
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**Body:**
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Ever heard of a Brownian bridge? It's one of those elegant mathematical objects that sounds fancy but has a simple intuition.
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**ELI5:** Imagine you're a drunk person doing a random walk, but you MUST end up exactly where you started. How does that constraint change your journey? That's the Brownian bridge.
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**The Math (in plain terms):**
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- Regular Brownian motion W(t) can wander anywhere
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- A Brownian bridge B(t) is conditioned to return to zero: B(0) = B(T) = 0
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- Formula: B(t) = W(t) - (t/T) × W(T)
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**Interesting Properties:**
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1. The mean is always zero
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2. Variance = t(T-t)/T - it's a parabola! Maximum uncertainty at the midpoint
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3. The process is Gaussian at every time point
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**What I Built:**
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- Simulated 10,000 sample paths
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- Verified boundary conditions (exact to machine precision)
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- Confirmed variance formula (<1% error)
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- Ran Shapiro-Wilk normality test (passed)
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**Why It Matters:**
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- Statistics: The Kolmogorov-Smirnov test uses Brownian bridge properties
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- Finance: Variance reduction in Monte Carlo pricing
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- Physics: Modeling constrained polymer chains
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The code uses numpy for simulation and scipy for statistical tests. Each path is generated by first simulating standard Brownian motion, then applying the bridge transformation.
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**View the full interactive notebook:** https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/brownian_bridge.ipynb
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### Facebook (< 500 chars)
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Just finished exploring one of my favorite mathematical objects: the Brownian bridge.
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Imagine a random walk that MUST return to its starting point. How does it behave? Turns out the uncertainty is highest in the middle of the journey - when you're furthest from the constraints.
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I simulated 10,000 random paths and verified the math. The theory matches perfectly with computation.
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This has real applications in statistics, finance, and even physics!
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Check out the interactive notebook: https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/brownian_bridge.ipynb
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### LinkedIn (< 1000 chars)
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Computational Verification of Brownian Bridge Properties
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Today I completed a comprehensive simulation study of Brownian bridges - a fundamental stochastic process with applications across quantitative finance, statistical testing, and physics.
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Key methodology:
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- Implemented direct construction: B(t) = W(t) - (t/T)W(T)
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- Generated 10,000 Monte Carlo sample paths
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- Verified theoretical properties against empirical estimates
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Results:
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- Boundary conditions: B(0) = B(T) = 0 (exact to machine precision)
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- Variance at midpoint: 0.2499 empirical vs 0.25 theoretical (<1% relative error)
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- Covariance structure: Confirmed Cov(B(s),B(t)) = s(1-t/T)
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- Shapiro-Wilk test: Confirms Gaussian marginal distributions
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This work demonstrates the importance of computational validation in stochastic analysis. The Brownian bridge appears in the Kolmogorov-Smirnov test, variance reduction techniques for Monte Carlo simulation, and models of constrained physical systems.
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Tools: Python, NumPy, SciPy, Matplotlib
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View the full analysis: https://cocalc.com/github/Ok-landscape/computational-pipeline/blob/main/notebooks/published/brownian_bridge.ipynb
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#QuantitativeFinance #Stochastics #Python #DataScience #Mathematics #MonteCarlo
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### Instagram (< 500 chars)
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Brownian Bridges: Random Walks That Come Home
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This visualization shows 20 sample paths of a Brownian bridge - random motion constrained to start and end at zero.
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The red shaded region? That's the theoretical uncertainty envelope.
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Notice how paths spread out in the middle but are forced together at the boundaries.
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Variance formula: t(T-t)/T
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Maximum uncertainty: exactly at the midpoint
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10,000 simulated paths confirm the math.
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Beautiful when theory meets computation.
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#mathematics #probability #dataviz #python #stochastics #coding #science #math #randomwalk #montecarlo
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