Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Adiabatic Vacua and Hadamard States for Scalar Quantum Fields on Curved
  Spacetime   Quasifree states of a linear Klein-Gordon quantum field on globally
hyperbolic spacetime manifolds are considered. Using techniques from the theory
of pseudodifferential operators and wavefront sets on manifolds a criterion for
a state to be an Hadamard state is developed. It is shown that ground- and
KMS-states on certain static spacetimes and adiabatic vacuum states on
Robertson-Walker spaces are Hadamard states. Finally, the problem of
constructing Hadamard states on arbitrary curved spacetimes is solved in
principle.

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The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph