Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Suppressing Proton Decay By Separating Quarks And Leptons   Arkani-Hamed and Schmaltz (AS) have shown that proton stability need not
originate from symmetries in a high energy theory. Instead the proton decay
rate is suppressed if quarks and leptons are spatially separated in a compact
extra dimension. This separation may be achieved by coupling five dimensional
fermions to a bulk scalar field with a non-trivial vacuum profile and requires
relationships between the associated quark and lepton Yukawa couplings. We
hypothesise that these relationships are the manifestation of an underlying
symmetry. We further show that the AS proposal may suggest that proton
stability \emph{is} the result of an underlying symmetry, though not
necessarily the traditional baryon number symmetry.

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The categories of this paper are: econ
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
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The categories of this paper are: q-fin
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-th
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The categories of this paper are: comp-gas
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph