Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fermion mass hierarchy and non-hierarchical mass ratios in SU(5) x
  U(1)_F   We consider a SU(5) x U(1)_F GUT-flavor model in which the number of effects
that determine the charged fermions Yukawa matrices is much larger than the
number of observables, resulting in a hierarchical fermion spectrum with no
particular regularities. The GUT-flavor symmetry is broken by flavons in the
adjoint of SU(5), realizing a variant of the Froggatt-Nielsen mechanism that
gives rise to a large number of effective operators. By assuming a common mass
for the heavy fields and universality of the fundamental Yukawa couplings, we
reduce the number of free parameters to one. The observed fermion mass spectrum
is reproduced thanks to selection rules that discriminate among various
contributions. Bottom-tau Yukawa unification is preserved at leading order, but
there is no unification for the first two families. Interestingly, U(1)_F
charges alone do not determine the hierarchy, and can only give upper bounds on
the parametric suppression of the Yukawa operators.

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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
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The categories of this paper are: econ
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The categories of this paper are: q-bio
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-th
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The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
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The categories of this paper are: stat
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: physics
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The categories of this paper are: nlin
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The categories of this paper are: solv-int