Cohen-Macaulay mod-ules on hypersurface singularities II.
The aim of these notes is to generalize Laumon’s construction [20] of automorphic sheaves corresponding to local systems on a smooth, projective curve to the case of local systems with indecomposable unipotent ramification at a finite set of points. To this end we need an extension of the notion of parabolic structure on vector bundles to coherent sheaves. Once we have defined this, a lot of arguments from the article “ On the geometric Langlands conjecture” by Frenkel, Gaitsgory and Vilonen [11]...
We prove that the category of Laumon 1-motives up to isogenies over a field of characteristic zero is of cohomological dimension . As a consequence this implies the same result for the category of formal Hodge structures of level (over ).
Let denote an ideal in a Noetherian ring R, and M a finitely generated R-module. We introduce the concept of the cohomological dimension filtration , where c = cd(,M) and denotes the largest submodule of M such that . Some properties of this filtration are investigated. In particular, if (R,) is local and c = dim M, we are able to determine the annihilator of the top local cohomology module , namely . As a consequence, there exists an ideal of R such that . This generalizes the main results...