Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Canonical quantization of the relativistic particle in static spacetimes   We perform the canonical quantization of a relativistic spinless particle
moving in a curved and static spacetime. We show that the classical theory
already describes at the same time both particle and antiparticle. The analyses
involves time-depending constraints and we are able to construct the
two-particle Hilbert space. The requirement of a static spacetime is necessary
in order to have a well defined Schr\"odinger equation and to avoid problems
with vacuum instabilities. The severe ordering ambiguities we found are in
essence the same ones of the well known non-relativistic case.

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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: econ
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The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
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The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph
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The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat