The characteristic class and ramification of an l-adic etale sheaf
Algebraic Geometry
2010-05-18 v1
Abstract
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 (math.AG/0402010) and the other is the 0-cycle class defined by Kato for rank 1 sheaves.
Keywords
Cite
@article{arxiv.math/0604121,
title = {The characteristic class and ramification of an l-adic etale sheaf},
author = {Ahmed Abbes and Takeshi Saito},
journal= {arXiv preprint arXiv:math/0604121},
year = {2010}
}
Comments
45 pages, Latex