Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probabilistic interpretation of the wave function for the Bianchi I
  model   We compare two different approaches for quantization of the Bianchi I model:
a reduced phase space quantization, in which the isotropic Misner variables is
taken as time, and the Vilenkin proposal, in which a semiclassical
approximation is performed for the same variable. We outline the technical and
interpretative issues of these two methods and we demonstrate that they provide
equivalent results only if the dynamics is essentially dictated by the
isotropic matter contribution.

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The categories of this paper are: math
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The categories of this paper are: ao-sci
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: astro-ph
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The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg