Unique ergodicity on compact homogeneous spaces
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Abstract:
Extending results of a number of authors, we prove that if $U$ is the unipotent radical of an $\mathbb {R}$-split solvable epimorphic subgroup of a real algebraic group $G$ which is generated by unipotents, then the action of $U$ on $G/\Gamma$ is uniquely ergodic for every cocompact lattice $\Gamma$ in $G$. This gives examples of uniquely ergodic and minimal two-dimensional flows on homogeneous spaces of arbitrarily high dimension. Our main tools are the Ratner classification of ergodic invariant measures for the action of a unipotent subgroup on a homogeneous space, and a simple lemma (the ‘Cone Lemma’) about representations of epimorphic subgroups.References
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Additional Information
- Barak Weiss
- Affiliation: Department of Mathematics, State University of New York at Stony Brook, Stony Brook, New York 11794
- MR Author ID: 335552
- ORCID: 0000-0002-9296-3343
- Email: barak@math.sunysb.edu
- Received by editor(s): April 22, 1999
- Published electronically: August 28, 2000
- Communicated by: Michael Handel
- © Copyright 2000 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 129 (2001), 585-592
- MSC (1991): Primary 22F30
- DOI: https://doi.org/10.1090/S0002-9939-00-05791-9
- MathSciNet review: 1800240