Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Metric of a tidally distorted, nonrotating black hole   The metric of a tidally distorted, nonrotating black hole is presented in a
light-cone coordinate system that penetrates the event horizon and possesses a
clear geometrical meaning. The metric is expressed as an expansion in powers of
r/R << 1, where r is a measure of distance from the black hole and R is the
local radius of curvature of the external spacetime; this is assumed to be much
larger than M, the mass of the black hole. The metric is calculated up to a
remainder of order (r/R)^4, and it depends on a family of tidal gravitational
fields which characterize the hole's local environment. The coordinate system
allows an easy identification of the event horizon, and expressions are derived
for its surface gravity and the rates at which the tidal interaction transfers
mass and angular momentum to the black hole.

1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat