Dividing the Solar Year

A slice of the celestial pi.

The mean Tropical Year 365.24219 or 365.24217 days.

Mean Solar Crust

The solar calendars of the world organize the year into 365 days to approximate the Tropical Year. If it is important to keep the solar calendar in synch with the Tropical Year, then a leap day is added periodically.

The year is not a given, as there are various ways to measure and define the Earth’s orbit around the Sun relative to its rotation around its axis. If we use the ephemeris day, exactly 86,400 seconds, then the mean Tropical Year is 365.24219. If we use mean solar days, it works out to 365.24217.

the Peculiar Math That Could Underlie the Laws of Nature

New findings are fueling an old suspicion that fundamental particles and forces spring from strange eight-part numbers called “octonions.”

Reblog from Quanta Magazine

In 2014, a graduate student at the University of Waterloo, Canada, named Cohl Furey rented a car and drove six hours south to Pennsylvania State University, eager to talk to a physics professor there named Murat Günaydin. Furey had figured out how to build on a finding of Günaydin’s from 40 years earlier — a largely forgotten result that supported a powerful suspicion about fundamental physics and its relationship to pure math.