Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Equivalence Principle and Field Quantization in Curved Spacetime   To comply with the equivalence principle, fields in curved spacetime can be
quantized only in the neighborhood of each point, where one can construct a
freely falling M i n k o w s k i frame with z e r o curvature. In each such
frame, the geometric forces of gravity can be replaced by a selfinteracting
spin-2 field, as proposed by Feynman in 1962. At a n y fixed distance $R$ from
a black hole, the vacuum in each freely falling volume element acts like a
thermal bath of all particles with Unruh temperature T_U=\hbar GM/2\pi c R^2.
At the horizon R=2GM/c^2, the falling vacua show the Hawking temperature
T_H=\hbar c^3/8\pi GMk_B.

11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ