Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quasi-Periodic Oscillations in Relativistic Tori   Motivated by recent interesting work on p-mode oscillations in axisymmetric
hydrodynamic black-hole tori by Rezzolla, Zanotti, and collaborators, I explore
the robustness of these oscillations by means of two and three-dimensional
relativistic hydrodynamic and MHD simulations. The primary purpose of this
investigation is to determine how the amplitudes of these oscillations are
affected by the presence of known instabilities of black-hole tori, including
the Papaloizou-Pringle instability (PPI) and the magneto-rotational instability
(MRI). Both instabilities drive accretion at rates above those considered in
Rezzolla's work. The increased accretion can allow wave energy to leak out of
the torus into the hole. Furthermore, with the MRI, the presence of turbulence,
which is absent in the hydrodynamic simulations, can lead to turbulent damping
(or excitation) of modes. The current numerical results are preliminary, but
suggest that the PPI and MRI both significantly damp acoustic oscillations in
tori.

4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg