Simon Willison’s Weblog

2 items tagged “maths”

Google Image Charts: Mathematical (TeX) Formulas (via) I’m not sure when they added this, but you can now use the Google Charts Image API to render mathematical formulas, specified using TeX syntax. Wordpress.com and Wikipedia have both offered this feature for quite a while, but now you can use it anywhere on the Web. # 12th February 2010, 9:42 am

GPS and Relativity (via) GPS satellite clock ticks need an accuracy of 20-30 nanoseconds. The satellites move fast enough that their clocks fall behind by 7 microseconds a day due to time dilation, but orbit high enough that the curvature of spacetime due to the Earth’s mass puts them forward by another 45 microseconds. GPS receivers have to perform relativistic calculations to determine their location! # 11th January 2010, 9:17 am