Extensions of pro-affine algebraic groups

Brian Lee Peterson

Vol. 77 (1978), No. 1, 189–231

DOI: 10.2140/pjm.1978.77.189

Abstract

Our objective is to make a series of reductions for the problem of computing Ext in the category of pro-affine algebraic groups over an algebraically closed field of characteristic zero, exploiting the notions of unipotence, reductiveness, and group coverings. After examining some of the properties of Ext in a more general categorical setting, due to G. Hochschild, we discuss the multiplicative character theory for our groups and obtain several consequences of simple connectedness before proceeding to the main objective.

Mathematical Subject Classification 2000

Primary: 14L25, 14L25

Secondary: 18G99

Milestones

Received: 14 July 1977

Published: 1 July 1978