2 00 1 Computing the equivariant Euler characteristic of Zariski and étale sheaves on curves
نویسنده
چکیده
The object of this paper is to develop and prove an equivariant Grothendieck-OggShafarevich formula. Let k be an algebraically closed field, X a connected smooth projective curve over k and G a finite subgroup of Aut(X/k) of order n. Furthermore, let l 6= char(k) be a prime and F a constructible Fl-sheaf on the étale site Xét which carries a G-action compatible with the given G-action on X. The following task may be viewed as a Riemann-Roch problem: Compute the equivariant Euler characteristic
منابع مشابه
Computing the equivariant Euler characteristic of Zariski and étale sheaves on curves
We prove an equivariant Grothendieck-Ogg-Shafarevich formula. This formula may be viewed as an étale analogue of well-known formulas for Zariski sheaves which were proved by Ellingsrud/Lønsted and Nakajima and for which we give a new approach in this paper. Mathematics Subject Classification 2000. 14F20; 14L30; 14H30.
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تاریخ انتشار 2001