Irrationality problems

Algebro-Geometric and Homotopical Methods

16 February 11:00 - 12:00

Alena Pirutka - Courant Institute of Mathematical Sciences

Let X be a projective algebraic variety, the set of solutions of a system of homogeneous polynomial equations. Several classical notions describe how "unconstrained" the solutions are, i.e., how close X is to projective space: there are notions of rational, unirational and stably rational varieties. Over the field of complex numbers, these notions coincide in dimensions one and two, but diverge in higher dimensions. In this talk I will discuss classical and recent advances in this area, examples and deformation properties.
Eric M. Friedlander
University of Southern California
Lars Hesselholt
University of Copenhagen
Paul Arne Østvaer
University of Oslo


Paul Arne Østvaer


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