Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Black-hole dynamics in BHT massive gravity   Using an exact Vaidya-type null-dust solution, we study the area and entropy
laws for dynamical black holes defined by a future outer trapping horizon in
(2+1)-dimensional Bergshoeff-Hohm-Townsend (BHT) massive gravity. We consider
the theory admitting a degenerate (anti-)de Sitter vacuum and pure BHT gravity.
It is shown that, while the area of a black hole decreases by the injection of
a null dust with positive energy density in several cases, the Wald-Kodama
dynamical entropy always increases.

0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex