Oct 22, 2004 - Claremont, Calif. -

Have you ever wondered how different cultures counted the year and how calendars came about? Why do the Chinese New Year, the end of Ramandan, Deepavalik and Easter Sunday fall on different days each year?

The Gregorian Calendar is fairly simple, but the three others involve deep mathematical problems. There are simple rules of thumb that allow one to predict the date of Chinese New Year, the end of Ramadan and Deepavali with an error of, at most, one day.

Professor Helmer Aslaksen of the National University of Singapore will discuss the relationship between mathematics, astronomy and cultural aspects of the calendars at a free lecture "Heavenly Mathematics" in Galileo Hall at Harvey Mudd College, on Thursday, Oct. 28, at 7 p.m.