01
Drag a source
Grab either glowing core and move it. As the separation grows the fringes crowd tighter; as the sources close, the bands spread wide open.
Two-Source InterferenceField 150
Two coherent point sources ripple outward across the field above. Where crest lands on crest they add into bright antinodes; where crest meets trough they cancel into black nulls. The double-slit, made continuous — drag either source and the whole fringe pattern re-knits in real time.
The sum of two waves / 01
Each source sends out concentric rings — crest, trough, crest — expanding at the speed of the medium. Alone, either one is featureless. Together, their rings cross, and at every crossing the two heights simply add.
Along certain curves the path from one source is exactly a whole number of wavelengths longer than the path from the other. There, crest always lands on crest: a bright antinodal line that never goes dark. Halfway between, the difference is half a wavelength — crest forever cancels trough — and the water lies perfectly still. Those still curves are the nulls, and they are hyperbolas.
The field above is that arithmetic, evaluated a million times a second: instantaneous height mapped to light, with the fixed skeleton of fringes glowing steady beneath the shimmer.
Crest on crest. The two waves reinforce to double amplitude — the brightest, most restless bands in the field.
A single expanding ring of phase. Teal traces the travelling crests as they sweep out from each source.
Crest on trough. The heights sum to zero and hold there — the dark hyperbolic lanes that never light.
How to read the field / 02
Grab either glowing core and move it. As the separation grows the fringes crowd tighter; as the sources close, the bands spread wide open.
The slider stretches or shortens every ripple at once. Longer waves throw broad, lazy fringes; shorter waves pack them dense.
Nothing you do moves a null off its hyperbola — the geometry is fixed by path difference. Only the spacing between them breathes.