SilverCardioid

A Dutch software developer who occasionally makes stuff outside of work, and even more occasionally puts it online.

Cardi…what?

An animation of three definitions of the cardioid: (1) rolling circles; (2) caustic or envelope of reflecting rays inside a circle (or equivalently of angle-doubling chords); and (3) inversion of a parabola through a circle.

A cardioid (car-dee-oid) is a mathematical curve resembling a rounded heart. It is the shape traced by a point on a circle rolling around another circle of the same size. It appears in several other places in (and beyond) maths, including in certain circle chords, inversions of parabolae, microphones and coffee cups. I decided to use it as a screen name after noticing its similiarity to the Frisian pompeblêd symbol.

This site’s logo is naturally based on the cardioid too, and references some of its other properties: its prominence in the Mandelbrot set fractal (where it’s conveniently oriented to fit the letter “C” in), as well as its evolute, another cardioid that is one third the size and faces the other way. (Hover on the banner image to see an animated construction of the shapes in the logo, or see a full-screen version.)

Project maintained by SilverCardioid Hosted on GitHub Pages — Midnight Theme