Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Disclination classes, fractional excitations, and the melting of quantum
  liquid crystals   We consider how fractional excitations bound to a dislocation evolve as the
dislocation is separated into a pair of disclinations. We show that some
dislocation-bound excitations (such as Majorana modes and half-quantum
vortices) are possible only if the elementary dislocation consists of two
inequivalent disclinations, as is the case for stripes or square lattices but
not for triangular lattices. The existence of multiple inequivalent
disclination classes governs the two-dimensional melting of quantum liquid
crystals (i.e., nematics and hexatics), determining whether superfluidity and
orientational order can simultaneously vanish at a continuous transition.

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The categories of this paper are: alg-geom
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
1
The categories of this paper are: cs
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin