Transfer of ideals and quantization of small nilpotent orbits

Victor Protsak

Published 2008-02-14Version 1

We introduce and study a transfer map between ideals of the universal enveloping algebras of two members of a reductive dual pair of Lie algebras. Its definition is motivated by the approach to the real Howe duality through the theory of Capelli identities. We prove that this map provides a lower bound on the annihilators of theta lifts of representations with a fixed annihilator ideal. We also show that in the algebraic stable range, transfer respects the class of quantizations of nilpotent orbit closures. As an application, we explicitly describe quantizations of small nilpotent orbits of general linear and orthogonal Lie algebras and give presentations of certain rings of algebraic differential operators. We consider two algebraic versions of Howe duality and reformulate our results in terms of noncommutative Capelli identities.