4 papers
A symplectic approach to van den Ban's convexity theorem
Philip Foth, Michael Otto
Let G be a complex semisimple Lie group and τa complex antilinear involution that commutes with the Cartan involution. If H denotes the connected subgroup of τ-fixed points in G, a…
A refinement of the complex convexity theorem via symplectic techniques
Bernhard Kroetz, Michael Otto
We apply techniques from symplectic geometry to extend and give a new proof of the complex convexity theorem of Gindikin-Kroetz.
Lagrangian submanifolds and moment convexity
Bernhard Kroetz, Michael Otto
We consider a Hamiltonian torus action on a compact connected symplectic manifold M. For a certain class of Lagrangian submanifolds Q of M we show that the image of Q under the mom…
A Convexity property for the SO(2,C)-double coset decomposition of SL(2,C) and applications to spherical functions
Bernhard Kroetz, Michael Otto
We make a fine study of the SO(2,C)-double coset decomposition in SL(2,C) and give a full description of the intersection of the various cells with the complex crown Xi of SL(2,R)/…