Journal of Convex Analysis 08 (2001), No. 2, 291--326
Copyright Heldermann Verlag 2001
Invariant Convex Sets in Operator Lie Algebras
Andreas Neumann
Fachbereich Mathematik, Technische Universität, Schlossgartenstr. 7, 64289 Darmstadt, Germany
We study the closed convex subsets of Lie algebras of bounded linear operators on a Hilbert space that are invariant under the corresponding group of unitary operators. We will give a family fj of convex functions such, that for each closed convex invariant set C there are real numbers cj satisfying C = { X : fj(X) ≤ cj for all j }.
[ Fulltext-pdf (884 KB)]