Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lambda<0 Quantum Gravity in 2+1 Dimensions I: Quantum States and Stringy
  S-Matrix   We consider the theory of pure gravity in 2+1 dimensions, with negative
cosmological constant. The theory contains simple matter in the form of point
particles; the later are classically described as lines of conical
singularities. We propose a formalism in which quantum amplitudes for process
involving black holes and point particles are obtained as Liouville field
theory (LFT) correlation functions on Riemann surfaces X. Point particles are
described by LFT vertex operators, black holes (asymptotic regions) are in
correspondence with boundaries of X. We analyze two examples: the amplitude for
emission of a particle by the BTZ black hole, and the amplitude of black hole
creation by two point particles. We then define an inner product between
quantum states. The value of this inner product can be interpreted as the
amplitude for one set of point particles to go into another set producing black
holes. The full particle S-matrix is then given by the sum of all such
amplitudes. This S-matrix is that of a non-critical string theory, with the
world-sheet CFT being essentially the Liouville theory. Lambda<0 quantum
gravity in 2+1 dimensions is thus a string theory.

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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: cond-mat
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn
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The categories of this paper are: physics
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The categories of this paper are: astro-ph
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
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The categories of this paper are: econ
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The categories of this paper are: atom-ph
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The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
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The categories of this paper are: nucl-ex