# FELLESKOLLOKVIUM FREDAG 13. OKTOBER 2006

## Helmer Aslaksen : "Highlights of Mathematics in Astronomy and Art."

For many years I was dreaming about the opportunity to teach a multi-disciplinary mathematics course that could make students appreciate the beauty and relevance of mathematics. In 2001 the National University of Singapore introduced a General Education Requirement, and I introduced two new courses: "Heavenly Mathematics & Cultural Astronomy" and "Mathematics in Art and Architecture".

The main goal of my courses is to show that mathematics can answer fascinating questions about astronomy and arts. In this talk I will give some samples of such topics.

Most astronomy books are written from a "high-northern-latitude-centric" point of view. I will start by discussing the motion of the Sun and the Moon from a "hemispherically-correct" point of view. Which day does the Sun rise earliest in San Francisco, Singapore or Sydney? How do you tell the difference between a waxing crescent Moon and a waning crescent Moon in San Francisco, Singapore or Sydney? What is "wrong" with the Singapore flag from an astronomical point of view? Why do clocks go clockwise? What does the orbit of the Moon around the Sun look like?

In Singapore we use the Chinese, Muslim, Indian and Gregorian calendar to determine public holidays. How to determine the date of Chinese New Year and Ramadan?

We all know that perspective in paining involves mathematics, but the relationship turns out to involve a subtle combination of mathematics, physiology and psychology. What will a sphere look like when painted in perspective? Why have many scholars suspected that Johannes Vermeer (1632-1675) used a camera obscura?

I hope that this talk will make you more conscious of the mathematics of the world around you, and give you knowledge that you will enjoy sharing with others for the rest of your life.

Biographical information:

Associate Professor Helmer Aslaksen was born in Oslo, Norway, and did his undergraduate degree at the University of Oslo. After receiving his Ph.D. at the University of California, Berkeley, he joined the Department of Mathematics at the National University of Singapore in 1989.

His interests include geometry, Lie groups, and the relationship between mathematics and astronomy and art.

He has been academic advisor for the exhibitions Art Figures: Mathematics in Art at the Singapore Art Museum and The Dating Game - Calendars and Time in Asia at the Asian Civilisation Museum and for the TV series Ancient Chinese Inventions on the Discovery Channel. He was also on the Program Committee and a judge for The Great Science Challenge, a TV Science Quiz for secondary school students.

He has an extensive web site, including a highly ranked page on the Chinese calendar.

At the National University of Singapore he has introduced two General Education Modules, Heavenly Mathematics:Cultural Astronomy and Mathematics in Art and Architecture.

In 2004 he was awarded the Outstanding Educator Award at the National University of Singapore.

1430-1530 i pausearealet i 7. etage
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