Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Black holes, the Wheeler-DeWitt equation and the semi-classical
  approximation   The definition of matter states on spacelike hypersurfaces of a 1+1
dimensional black hole spacetime is considered. Because of small quantum
fluctuations in the mass of the black hole, the usual approximation of treating
the gravitational field as a classical background on which matter is quantized,
breaks down near the black hole horizon. On any hypersurface that captures both
infalling matter near the horizon and Hawking radiation, a semiclassical
calculation is inconsistent. An estimate of the size of correlations between
the matter and gravity states shows that they are so strong that a fluctuation
in the black hole mass of order exp[-M/M_{Planck}] produces a macroscopic
change in the matter state. (Talk given at the 7th Marcel Grossmann Meeting on
work in collaboration with E. Keski-Vakkuri, G. Lifschytz and S. Mathur.)

25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph