The second Lie algebra cohomology group and Weyl modules
The second Lie algebra cohomology group and Weyl modules
Dedicated to Gerhard Hochschild on the occasion of his 65th birthdayThe Lie algebra 1-cohomology of classical Lie algebras in characteristic p is nonzero at some modules.In fact, Hochschild showed that the restricted 1-cohomology is nonzero.Here I will systematically produce Weyl modules at which the (unrestricted) 2-cohomology is nonzero.This will provide …