Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Variational Multi-Time Green's Functions for Nonequilibrium Quantum
  Fields   The time-dependent variational principle proposed by Balian and Veneroni is
used to provide the best approximation to the generating functional for
multi-time Green's functions of a set of (bosonic) observables $Q_{\mu)$. By
suitably restricting the trial spaces, the computation of the two-time Green's
function, obtained by a second order expansion in the sources, is considerably
simplified. This leads to a tractable formalism suited to quantum fields out of
equilibrium. We propose an illustration on the finite temperature ${\bf\Phi^4}$
theory in curved space and coupled to gravity.

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The categories of this paper are: math
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
1
The categories of this paper are: cs
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The categories of this paper are: stat
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The categories of this paper are: hep-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: q-alg
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The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph