Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mass Differences within Isotopic Multiplets in a SUSY Electro-weak
  Theory   Based on the idea that electromagnetism is responsible for the mass
differences within isotopic multiplets, and possibly also for the whole mass of
the electron, a supersymmetric gauge theoretical model based on the group
$SU(2)_{L} \times SU(2)_{R} \times U(1)_{Y}$ is constructed. Under some
reasonable assumptions to the SUSY particle spectrum, a correct sign for the
mass difference within an isotopic multiplet is obtained. This might provide a
possible scenario to understand the old puzzle of the proton-neutron mass
difference.

3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph