Pentagrama Myrificum, old wine into new wineskins

School of Mathematics Colloquium
Thursday, February 4, 2010 - 11:05am for 1 hour (actually 50 minutes)
Skiles 269
Sergei Tabachnikov – Penn State University
Guillermo Goldsztein

Please Note: Refreshments at 4PM in Skiles 236

The Pentagram map is a projectively natural iteration on plane polygons. Computer experiments show that the Pentagram map has quasi-periodic behavior. I shall explain that the Pentagram map is a completely integrable system whose continuous limit is the Boussinesq equation, a well known integrable system of soliton type. As a by-product, I shall demonstrate new configuration theorems of classical projective geometry.