The Double-Slit Experiment: Unveiling Quantum Mystery

This simulation demonstrates wave-particle duality. The histogram (particle count on the right) is built rapidly by a background Web Worker simulating many particles. A separate, fixed number of purely visual particles are simulated on the main thread for smooth animation (their speed is unaffected by "Sim Speed Multiplier").

Wave-like Behavior (Observer OFF)

Particles behave like waves, passing through both slits simultaneously and interfering, creating the characteristic interference pattern in the histogram.

Particle-like Behavior (Observer ON)

Observing which slit a particle uses forces it to act like a particle, going through only one slit. The interference pattern vanishes, replaced by two distinct clumps in the histogram.

Use Sim Speed Multiplier (affects worker only) and Sim Rate (Worker) to accelerate histogram accumulation. Changing any slider/toggle resets the simulation.

Path Integral Explorer

Illustrates Feynman's Path Integral formulation: a particle explores all possible paths simultaneously from A to B. Each path's "action" (simplified as length) determines its contribution. Paths near the least action path (bright green) contribute most. Drag A & B (paths update on release) or use sliders (paths update after you stop) to explore.