Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Turbulence and Araki-Woods factors   Using Baire category techniques we prove that Araki-Woods factors are not
classifiable by countable structures. As a result, we obtain a far reaching
strengthening as well as a new proof of the well-known theorem of Woods that
the isomorphism problem for ITPFI factors is not smooth. We derive as a
consequence that the odometer actions of Z that preserve the measure class of a
finite non-atomic product measure are not classifiable up to orbit equivalence
by countable structures.

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The categories of this paper are: alg-geom
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The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
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The categories of this paper are: stat
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The categories of this paper are: econ
26
The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: ao-sci
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The categories of this paper are: eess
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The categories of this paper are: hep-th
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex