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arXiv · 1201.5367

Rigidity of group actions on homogeneous spaces, III

Uri Bader·Alex Furman·Alex Gorodnik·Barak Weiss
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Abstract

Consider homogeneous G/H and G/F, for an S-algebraic group G. A lattice {\Gamma} acts on the left strictly conservatively. The following rigidity results are obtained: morphisms, factors and joinings defined apriori only in the measurable category are in fact algebraically constrained. Arguing in an elementary fashion we manage to classify all the measurable {\Phi} commuting with the {\Gamma}-action: assuming ergodicity, we find they are algebraically defined.

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Uri Bader, Alex Furman, Alex Gorodnik, Barak Weiss. 2012-01-25. Rigidity of group actions on homogeneous spaces, III. https://doi.org/10.1215/00127094-2860021

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