Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-Riemannian acoustic black holes: Hawking radiation and Lorentz
  symmetry breaking   A non-Riemannian geometrical approach to the investigation of an acoustic
black hole in irrotational mean flows, based on the Lighthill vortex sound
theory is given. This additional example of analog gravity based on classical
fluids is used to investigate the acoustic Lorentz violation. An example is
given where the contortion vector is distributed along a ring inside the fluid
which can be gravitational analog of the torsion thick string spacetime defect.
It is found that the linear background flow velocity approximation, acoustic
Lorentz symmetry is breaking by the acoustic Cartan contortion in analogy to
the spontaneous gravitational Lorentz breaking in Riemann-Cartan spacetime
discovered recently by Kostelecky. We also show that although the acoustic
torsion contributes to the fiducial observer acceleration, it is not present in
Hawking radiation since is not presnt in the surface gravity of the acoustic
black hole.

35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess