Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fermion masses and mixing angles from gauge symmetries   The structure of the quark and lepton masses and mixing angles provides one
of the few windows we have on the underlying physics generating the \sm. In an
attempt to identify the underlying symmetry group we look for the simplest
gauge extension of the SUSY standard model capable of generating the observed
structure. We show that the texture structure and hierarchical form found in
the (symmetric) quark and lepton mass matrices follows if one extends the gauge
group of the standard model to include an horizontal $U(1)$ gauge factor,
constrained by the need for anomaly cancellation. This $U(1)$ symmetry is
spontaneously broken slightly below the unification/string scale leaving as its
only remnant the observed structure of masses and mixings. Anomaly cancellation
is possible only in the context of superstring theories via the Green Schwarz
mechanism with $sin^2(\theta_W)=3/8$.

28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat