tirra

A tour of tirra

Sun, 09 Aug 2026 00:00:00 +0000

The demo note shows off most of the theme’s features in one place.

Callouts

[!note] Note Blockquotes that start with > [!type] render as a labeled callout. The supported types are note, info, tip, important, warning, alert, and error.

The Shape of Orbits

Mon, 02 Mar 2026 00:00:00 +0000

Two facts: force falls off as the inverse square, and angular momentum is conserved are enough to derive the whole family of orbits: circles, ellipses, parabolas, hyperbolas. This note walks the geometry step by step, no calculus of variations required.

Fourier, from First Principles

Thu, 15 Jan 2026 00:00:00 +0000

Every periodic signal is a sum of sines, the hard part is believing it, then finding the coefficients. This note builds the Fourier transform up from a single idea: sines of different frequencies are orthogonal, so you can pick each one out by taking a dot product.