Bloch and Kato's exponential map: three explicit formulas

The purpose of this article is to give formulas for Bloch-Kato's exponential map and its dual for an absolutely crystalline p-adic representation V, in terms of the (phi,Gamma)-module associated to that representation. As a corollary of these computations, we can give a very simple (and slightly improved) description of Perrin-Riou's exponential map (which interpolates Bloch-Kato's exponentials for V(k)). This new description directly implies Perrin-Riou's reciprocity formula.Comment: 22 pages, in englis

A vanishing theorem for Fano varieties in positive characteristic

We prove a Kodaira-type vanishing theorem for the Witt vector sheaf on a Fano variety over a perfect field of characteristic p. As a corollary, we deduce that the number of rational points on a Fano variety over a finite field with q=p^n elements is congruent to 1 mod q. This refines a result of Esnault which say that the number is congruent to 1 mod p.Comment: A correct proof of the original vanishing theorem (mod torsion) has been given in the meanwhile by Esnault. This note strengthens that result slightl

Coleman Maps for Modular Forms at Supersingular Primes over Lubin-Tate Extensions

Given an elliptic curve with supersingular reduction at an odd prime p, Iovita and Pollack have generalised results of Kobayashi to define even and odd Coleman maps at p over Lubin-Tate extensions given by a formal group of height 1. We generalise this construction to modular forms of higher weights.Comment: Some really minor changes from the previous version, almost identical to the published versio