Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Echoes in brane worlds: ringing at a black hole--wormhole transition   Echoes are known as modifications of the usual quasinormal ringing of a black
hole at late times because of the deviation of space-time from the initial
black-hole geometry in a small region near its event horizon. We consider a
class of brane-world model solutions of the Shiromizu-Maeda-Sasaki equations,
which describe both black holes and wormholes and interpolate between them via
a continuous parameter. In this way the brane-world scenario provides a natural
model for wormholes mimicking the black hole behavior if the continuous
parameter is chosen near the threshold with a black-hole solution. We show that
in the vicinity of this threshold interpolating between black holes and
wormholes, quasinormal ringing of the wormholes at the initial stage is
indistinguishable from that of the black holes with nearby values of the above
parameter, but at later times the signal is modified by intensive echoes. We
notice that the black-hole mimickers that are wormholes near the threshold have
the largest quality factor and are therefore the best oscillators among the
considered examples.

26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn