Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fermion Mass Hierarchy in Six Dimensional SO(10) Grand Unified Theory on
  a $T^2/Z_2$ Orbifold   We suggest a simple supersymmetric SO(10) grand unified theory in 6
dimensions which produces the suitable fermion mass hierarchies. The 5th and
6th dimensional coordinates are compactified on a $T^2/Z_2$ orbifold. The gauge
and Higgs fields propagate in 6 dimensions while ordinal chiral matter fields
are localized in 4 dimensions. The orbifolding and boundary conditions realize
the gauge symmetry reduction,
  $SU(3)_C\times SU(2)_L \times U(1)_Y \times U(1)_X$, and the triplet-doublet
mass splitting. We introduce extra three sets of vector-like heavy fields: two
sets propagate in 6 dimensions and chiral fields which couple to them are
defined as the 1st generation, and one set propagates in 5 dimensions and
chiral fields which couple to them are defined as the 2nd generation. The
suitable fermion mass hierarchies are generated by integrating out these
vector-like heavy fields.

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The categories of this paper are: nucl-th
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The categories of this paper are: quant-ph
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
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The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
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The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
2
The categories of this paper are: math
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The categories of this paper are: eess
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The categories of this paper are: q-fin
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The categories of this paper are: bayes-an
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-th