A note on restriction theorems for semistable sheaves

Abstract

We prove a new restriction theorem for semistable sheaves on varieties in all characteristics strengthening previous results. We also prove restriction theorem for strong semistability for varieties with some non-negativity constrains on the cotangent bundle (e.g., most of Fano and Calabi-Yau varieties).Comment: 12 pages, to appear in Mathematical Research Letters, appendix contained serious error pointed out by Trivedi and it is removed in this versio