Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unitarity and Fermion Mass Generatation   Some years ago Appelquist and Chanowitz considered the scattering of
fermion--anti-fermion into a pair of longitudinal gauge bosons. Their
calculation established that unitarity implies that the physics giving mass to
a quark of mass $m_f$ must be below a mass scale of $16 \pi v^2 / m_f$ ($v=246$
GeV). This bound is a bit difficult to interpret, because the unitarity of
gauge boson scattering requires in any case that there be new physics, such as
a Higgs boson, with a mass lighter than this. This paper re-examines the
Appelquist-Chanowitz bound in order to clarify its meaning. This work uses toy
models with a singlet Higgs boson to unitarize gauge boson scattering, and
considers other possibilities for the new physics affecting the fermion mass.
This new physics has the effect of changing the Higgs
boson--fermion--anti-fermion coupling. New physics cannot significantly alter
this coupling unless it is substantially lighter than the Appelquist-Chanowitz
bound.

25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-ex