AtomSim: A Browser-Based Atom Solver That Lets You Break Physics Rules

Robotnics · reddit · 2026-08-10

AtomSim is a web app that solves atoms from scratch and visualizes the results. It calculates hydrogen using closed-form math and uses a custom Hartree-Fock solver for real atoms like carbon and argon. Users can view the results as a 3D electron cloud, a 2D slice, a radial plot, an energy-level diagram, or an emission spectrum.

A standout feature is the ability to intentionally break physics: users can switch off the Pauli exclusion principle, disable electron exchange, or input a custom potential V(r) to see what emerges. The project operates on the rule that the model never quietly lies—every number displayed carries a tag indicating exactly how it was derived (e.g., exact, numerical, approximation, or counterfactual).

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