Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Probabilistic Representation of the Ground State Expectation of
  Fractional Powers of the Boson Number Operator   We give a formula in terms of a joint Gibbs measure on Brownian paths and the
measure of a random-time Poisson process of the ground state expectations of
fractional (in fact, any real) powers of the boson number operator in the
Nelson model. We use this representation to obtain tight two-sided bounds. As
applications, we discuss the polaron and translation invariant Nelson models.

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The categories of this paper are: nucl-th
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
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The categories of this paper are: cs
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
3
The categories of this paper are: physics
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The categories of this paper are: mtrl-th
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The categories of this paper are: stat
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The categories of this paper are: cond-mat
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The categories of this paper are: funct-an
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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph