n-blocks collections on Fano manifolds and sheaves with regularity −∞

  • Edoardo Ballico Università di Trento
  • Francesco Malaspina Università di Torino
Keywords: m-block collection, Fano manifold, Coherent sheaves on a Fano manifold, Order of regularity

Abstract

Let X be a smooth Fano manifold equipped with a “ nice ” n-blocks collection in the sense of [3] and F a coherent sheaf on X . Assume that X is Fano and that all blocks are coherent sheaves. Here we prove that F has regularity −∞ in the sense of [3] if Supp(F) is finite, the converse being true under mild assumptions. The corresponding result is also true when X has a geometric collection in the sense of [2].

Author Biographies

Edoardo Ballico, Università di Trento
Dept. of Mathematics
38050 Povo (TN), Italy
Francesco Malaspina, Università di Torino
Università di Torino
via C. Alberto 10
10123 Torino, Italy
Published
2007-12-05
Section
Articoli