Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum gravitational collapse as a Dirac particle on the half-line   We show that the quantum dynamics of a thin spherical shell in general
relativity is equivalent to the Coulomb-Dirac equation on the half line. The
Hamiltonian has a one-parameter family of self-adjoint extensions with a
discrete energy spectrum $|E| < m$, and a continuum of scattering states for
$|E|>m$, where $m$ is the rest mass of the shell and $E$ is the
Arnowitt-Deser-Misner mass. For sufficiently large $m$, the ground state energy
level is negative. This suggests that classical positivity of energy does not
survive quantization. The scattering states provide a realization of
singularity avoidance. We speculate on the consequences of these results for
black hole radiation.

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The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex
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The categories of this paper are: physics
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The categories of this paper are: nlin
21
The categories of this paper are: adap-org
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The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex