Terence Tao on Nostr: In my most recent blog post ...

In my most recent blog post https://terrytao.wordpress.com/2024/12/19/quaternions-and-spherical-trigonometry/ I show how quaternions can be used to derive the equations of spherical trigonometry, and as an example derive the sunrise equation relating the time of sunrise or sunset to one's latitude and the declination of the Sun.