The characteristic class and ramification of an l-adic etale sheaf
成果类型：
Article
署名作者：
Abbes, Ahmed; Saito, Takeshi
署名单位：
Universite Paris 13; Centre National de la Recherche Scientifique (CNRS); University of Tokyo
刊物名称：
INVENTIONES MATHEMATICAE
ISSN/ISSBN：
0020-9910
DOI：
10.1007/s00222-007-0040-7
发表日期：
2007
页码：
567-612
关键词：
摘要：
We introduce the characteristic class of an l-adic etale sheaf using a cohomological pairing due to Verdier (SGA5). As a consequence of the Lefschetz-Verdier trace formula, its trace computes the Euler-Poincare characteristic of the sheaf. We compare the characteristic class to two other invariants arising from ramification theory. One is the Swan class of Kato-Saito [17] and the other is the 0-cycle class defined by Kato for rank 1 sheaves in [16].