Bjorn Poonen Date and time: Wed, 03/26/2008 - 4:00pm Physics Building, Room 202 Cantrell Lectures Wednesday, March 26, 2008 4:00pm, Physics Bldg., Room 202 Title of talk: Solved and unsolved problems in number theory Abstract: I will survey a few of my favorite problems in number theory, such as Fermat's last theorem (solved) and the rectangular box problem (unsolved). Thursday, March 27, 2008 3:30pm, Boyd Graduate Studies Bldg., Room 328 Title of talk: Hilbert's tenth problem Abstract: Hilbert dreamed that someday we would have a general method for solving all diophantine equations, but in 1970 it was proved that no such method exists. By-products of the proof include connections to prime-producing polynomials and the Riemann hypothesis. Friday, March 28, 20083:30pm, Boyd Graduate Studies Bldg., Room 328 Title of talk: Undecidability everywhere Abstract: Undecidable problems exist in many other subjects, such as group theory and topology. There are also a few problems in number theory and algebraic geometry whose decidability status is not yet known.