Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Three Inequivalent Mass-Degenerate Majorana Neutrinos and a Model of
  Their Splitting for Neutrino Oscillations   The mass matrix of three Majorana neutrinos of equal mass is not necessarily
proportional to the identity matrix, but expressible in terms of two angles and
one phase. We discuss how such a mass matrix may be stable or unstable against
radiative corrections. We then propose a model with additional explicit
breaking of the threefold degeneracy to account for the atmospheric neutrino
data, while the radiative breaking explains the solar neutrino data, using the
large-angle Mikheyev-Smirnov-Wolfenstein solution. Our model requires a nonzero
effective $\nu_e$ mass for neutrinoless double beta decay close to the present
experimental upper limit of 0.2 eV.

37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an