Constructions for infinitesimal group schemes
arXiv:0802.2918
Abstract
Let G be an infinitesimal group scheme over a field k of positive characteristic p. We introduce the global p-nilpotent operator , where V(G) is the scheme which represents 1-parameter subgroups of G. This operator applied to M encodes the local Jordan type of M, and leads to computational insights into the representation theory of G. For certain G-modules (including those of constant Jordan type), we employ the global p-nilpotent operator to associate various algebraic vector bundles on the projective scheme $\bP(G)$, the projectivization of the scheme of one-parameter subgroups of G. These vector bundles not only distinguish certain representations with the same local Jordan type, but also provide a method of constructing algebraic vector bundles on $\bP(G)$.
55 pages. This is a final version to appear in Transactions of the AMS. Significantly revised from the original preprint. In particular, last section is completely rewritten with some K_0 calculations added