Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Finite-temperature scalar fields and the cosmological constant in an
  Einstein universe   We study the back reaction effect of massless minimally coupled scalar field
at finite temperatures in the background of Einstein universe. Substituting for
the vacuum expectation value of the components of the energy-momentum tensor on
the RHS of the Einstein equation, we deduce a relationship between the radius
of the universe and its temperature. This relationship exhibit a maximum
temperature, below the Planck scale, at which the system changes its behaviour
drastically. The results are compared with the case of a conformally coupled
field. An investigation into the values of the cosmological constant exhibit a
remarkable difference between the conformally coupled case and the minimally
coupled one.

18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th
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The categories of this paper are: stat
30
The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int