Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Area scaling entropies for gravitating systems   The entropy of a spherically symmetric distribution of matter in
self-equilibrium is calculated. When gravitational effects are neglected, the
entropy of the system is proportional to its volume. As effects due to
gravitational self-interactions become more important, the entropy acquires a
correction term and is no longer purely volume scaling. In the limit that the
boundary of the system approaches its event horizon, the total entropy of the
system is proportional to its area. The scaling laws of the system's
thermodynamical quantities are identical to those of a black hole, even though
the system does not possess an event horizon.

33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
3
The categories of this paper are: physics
1
The categories of this paper are: cs