Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Boulware State and the Generalised Second Law of Thermodynamics   We show that the appropriate vacuum state for the interior of a box with
reflecting walls being lowered adiabatically into a Schwarzschild black hole is
the Boulware state. This is concordant with the results of Unruh and Wald, who
used a different approach to obtain the stress-energy inside the box. Some
comments about an entropy bound for ordinary matter, as first conjectured by
Bekenstein, are presented.

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The categories of this paper are: chem-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: nlin
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: acc-phys
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The categories of this paper are: cmp-lg
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The categories of this paper are: physics
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The categories of this paper are: q-alg
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The categories of this paper are: hep-th
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The categories of this paper are: q-fin
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The categories of this paper are: stat
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph