What happens behind the videos: the rules of each little world, how a collision becomes a note, and the checks we run before anything goes out.
How a payantha Short is made
Physics first, music second: how a simulation decides every note, why a note waits for the right frame, and what we measure before a video goes out.
How we check that a melody is public domain
The two-part test every song passes before we use it, the tricky cases (Für Elise, Canon in D, Carol of the Bells, Korobeiniki) and why we never use recordings.
Why a circle of light draws a heart
Put a lamp on the edge of a round mirror and the reflected light draws a heart by itself. The physics behind our heart video, with a demo you can run.
The ellipse trick: every ray arrives at once
Light leaving one focus of an elliptical mirror reaches the other focus after exactly the same distance, whatever its direction. Why, with a demo.
What our viewers taught us, in numbers
Lessons from publishing physics Shorts: why a repeated picture stalls, why long endings lose people, and why viewers spot bounces that look steered.