Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Volume dependent extension of Kerr-Newman black hole thermodynamics   We show that the Hawking--Bekenstein entropy formula is modified by a factor
of $8/3$ if one also considers a work term in the 1st law of thermodynamics by
a pressure stemming from the Hawking radiation. We give an intuitive definition
for the corresponding thermodynamical volume by the implicit definition
$\epsilon=Mc^2/V$, which is the average energy density of the Hawking
radiation. This volume scales as $V \sim M^5$, agreeing with other suggestions.
As a result the corresponding Smarr relation describes an extensive entropy and
a stable effective equation of state $S(E,V)\sim E^{3/4}V^{1/4}$. These results
pertain for charged and rotating Kerr-Newman black holes.

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The categories of this paper are: atom-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg
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The categories of this paper are: stat
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The categories of this paper are: solv-int
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The categories of this paper are: econ
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
9
The categories of this paper are: nlin