Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Black Hole Entropy is Thermodynamic Entropy   The comparison of geometrical properties of black holes with classical
thermodynamic variables reveals surprising parallels between the laws of black
hole mechanics and the laws of thermodynamics. Since Hawking's discovery that
black holes when coupled to quantum matter fields emit radiation at a
temperature proportional to their surface gravity, the idea that black holes
are genuine thermodynamic objects with a well-defined thermodynamic entropy has
become more and more popular. Surprisingly, arguments that justify this
assumption are both sparse and rarely convincing. Most of them rely on an
information-theoretic interpretation of entropy, which in itself is a highly
debated topic in the philosophy of physics. We discuss some of the pertinent
arguments that aim at establishing the identity of black hole surface area
(times a constant) and thermodynamic entropy and show why these arguments are
not satisfactory. We then present a simple model of a Black Hole Carnot cycle
to establish that black hole entropy is genuine thermodynamic entropy which
does not require an information-theoretic interpretation.

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The categories of this paper are: nucl-ex
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The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
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The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: funct-an
2
The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn