Around 1985, Gérard Laumon gave a proof of the local factorization of the determinant of the Frobenius map acting on the cohomology of a curve. Shortly before Laumon's work, however, Deligne had developed a different approach to the problem, which is not well known today. In this talk, I would like to introduce Deligne's method to a wider audience, in the hope that its full potential has yet to be exploited. Its starting point is Deligne's symmetric Künneth formula and the acyclicity properties of the Abel-Jacobi morphism, which led to the first proof of the result in the tame case. (Understanding Deligne's method is one part of an ongoing project with Joël Riou.)
By Ofer Gabber
By Geordie Williamson
By Mark Kisin
By Yves André
By Dennis Gaitsgory
By Ofer Gabber
By Yakov Varshavsky
By Fabrice Orgogozo
By Takeshi Saito
By Ofer Gabber
By Stephen Coombes , Peter Liddle
By Victor Kleptsyn
By Jean Feydy
By Albert Schwarz
