Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Physical Effects of the Gravitational $\Theta$-Parameter   We describe the effect of the gravitational $\Theta$-parameter on the
behavior of the stretched horizon of a black hole in $(3+1)$-dimensions. The
gravitational $\Theta$-term is a total derivative, however, it affects the
transport properties of the horizon. In particular, the horizon acquires a
third order parity violating, dimensionless transport coefficient which affects
the way localized perturbations scramble on the horizon. In the context of the
gauge/gravity duality, the $\Theta$-term induces a non-trivial contact term in
the energy-momentum tensor of a $(2+1)-$dimensional large-N gauge theory, which
admits a dual gravity description. As a consequence, the dual gauge theory in
the presence of the $\Theta$-term acquires the same third order parity
violating transport coefficient.

9
The categories of this paper are: nlin
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg