Light: Wave or Particle?
by UltraViper34An interactive demonstration of the double-slit experiment — one of the most famous puzzles in physics. Light arrives as discrete particles (photons) that land at single points on the detector, but while traveling it behaves like a wave that interferes with itself. Fire one photon at a time, then a thousand at once, and watch how the interference pattern emerges only from the statistics of many.
Frequently asked
What is the double-slit experiment?
The double-slit experiment is a demonstration that light (and matter) exhibits both wave-like and particle-like properties. When a stream of particles is fired through two narrow slits, an interference pattern appears on the detector behind them — characteristic of waves, not particles. The mystery is that even single particles fired one at a time still produce an interference pattern when many are accumulated.
Why does this interactive demo matter?
Seeing the interference pattern emerge from the statistics of individual photon impacts makes wave-particle duality concrete in a way a textbook diagram can't. You can fire a single photon, see it land somewhere on the detector, and only after firing hundreds do the bright and dark bands of the interference pattern reveal themselves.
Can I make a physics simulation like this and host it?
Yes. ArcadeLab hosts any single-file HTML interactive content — physics simulations, math toys, data visualizations, explorables. Paste a complete HTML file at arcadelab.ai/publish and you get a permanent shareable URL. No signup, no build tools.
What technology is this built with?
It's a single self-contained HTML file using the browser's 2D canvas API. No frameworks, no build step, no external assets. The entire experiment fits in one document — which makes it remixable: anyone can view the source and modify it.