DMM (Derived category, Mirror symmetry and McKay correspondence) seminar

Speaker: Dmitry Kaledin (Steklov)
Title: Witt vectors as a polynomial functor
Date (JST): Mon, Jan 31, 2011, 14:00 - 17:00
Place: Seminar Room A
Abstract: I want to revisit the classical construction of Witt vectors from a modern point of view. In particular, I will introduce a certain
two-parameter generalization of the Witt vectors functor, and I will use it to construct a version of the de Rham-Witt complex of Deligne and Illusie valid for any non-commutative algebra. In the process of doing so, I will also introduce a new computation-free construction of the product of Witt vectors; surprisingly, it uses Tate residue and the well-known central extension of Date-Jimbo-Kashiwara-Miwa. Since Witt vectors are somewhat esoteric for people not working in positive characteristic, I will not assume any familiarity with the subject at all and give all the necessary background.
Remarks: break at 15:00-15:30