Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurable Rigidity of actions on infinite measure homogeneous spaces,
  II   We consider the problems of measurable isomorphisms and joinings, measurable
centralizers and quotients for certain classes of ergodic group actions on
infinite measure spaces. Our main focus is on systems of algebraic origin:
actions of lattices and other discrete subgroups on homogeneous spaces G/H
where H is a sufficiently rich unimodular subgroup in a semi-simple group G. We
also consider actions of discrete subgroups of isometries Isom(X) of a pinched
negative curvature space X, acting on the space of horospheres Hor(X). For such
systems we prove that the only measurable isomorphisms, joinings, quotients
etc. are the obvious algebraic (or geometric) ones. This work was inspired by
the previous work of Shalom and Steger, but uses completely different
techniques which lead to more general results.

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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
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The categories of this paper are: cond-mat
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The categories of this paper are: supr-con
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The categories of this paper are: q-alg
1
The categories of this paper are: cs
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: alg-geom
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The categories of this paper are: plasm-ph
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: q-fin