February 16, 2026
Pretty dots, meltdown plots
Show HN: 2D Coulomb Gas Simulator
Hypnotic electron dots wow the crowd—until iPhones start crying
TLDR: A viral demo shows repelling dots settling into a neat, low‑energy pattern—beautiful and educational. The comments split between pure awe and practical warnings about phone‑freezing settings, plus a nerdy debate over “real” 2D physics and a requested toggle to compare force rules, highlighting both wonder and performance pitfalls.
A Show HN demo of swirling dots—think tiny charged marbles that all push away from each other—has the internet staring slack‑jawed. The creator’s 2D simulator hunts for the calmest, lowest‑energy layout (a fancy math thing called a Fekete configuration), and it’s rooted in real physics that shows up in everything from the fractional quantum Hall effect to superconductors. Translation: smart science, prettier screens.
But the vibe split fast. One camp can’t stop gushing—“mesmerizing” and “beautiful” are everywhere. The other camp? Waving a big red flag: crank up the animation smoothness and some phones freeze. One iPhone/Safari user claims the sim “breaks your phone,” prompting a wave of “Reduce particles!” PSAs and a mini‑meme about the world’s first “ASMR physics app that doubles as a stress test.”
Then came the nerd‑splainer thunder: in true 2D land, the push‑away force follows 1/r, not the usual 1/r² from high‑school physics. Cue calls for a toggle to compare both worlds, with one commenter saying they had to drop to 1,000 particles on mobile just to keep things moving. It’s part art piece, part lesson in physics, and part Safari boss fight—and the crowd is loving the drama as much as the dots.
Key Points
- •The simulator models a 2D Coulomb gas with electrons experiencing pairwise repulsion under an external potential.
- •Configuration energy is defined by the two-dimensional log-gas Hamiltonian.
- •The tool minimizes the Hamiltonian, approximating the zero-temperature Fekete configuration rather than sampling at finite temperature.
- •A 2017 result indicates the particle density near the boundary follows an erfc distribution.
- •Such Hamiltonians arise in diverse areas like the fractional quantum Hall effect, Hele-Shaw/Laplacian growth, and superconducting vortices.