Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Near-Horizon Geometry of an Evaporating Black Hole   The near-horizon geometry of evaporation black holes is determined according
to the semi-classical Einstein equation. We consider spherically symmetric
configurations in which the collapsing star has already collapsed below the
Schwarzschild radius. The back-reaction of the vacuum energy-momentum,
including Hawking radiation, is taken into account. The vacuum energy-momentum
plays a crucial role in a small neighborhood of the apparent horizon, as it
appears at the leading order in the semi-classical Einstein equation. Our study
is focused on the time-dependent geometry in this region.

12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess