Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Symmetry breaking, and the effect of matter density on neutrino
  oscillation   A proposal for the neutrino mass, based on neutrino-scalar field interaction,
is introduced. The scalar field is also non-minimally coupled to the Ricci
scalar and hence relates the neutrino mass to the matter density. In a dense
region, the scalar field obeys the $Z_2$ symmetry, and the neutrino is
massless. In a dilute region, the $Z_2$ symmetry breaks and neutrino acquires
mass from the non-vanishing expectation value of the scalar field. We consider
this scenario in the framework of a spherical dense object whose outside is a
dilute region. In this background, we study the neutrino flavors oscillation,
along with the consequences of the theory on oscillation length and MSW effect.
This preliminary model may shed some lights on the existing anomalies within
the neutrino data, concerning the different oscillating behavior of the
neutrinos in regions with different densities.

18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an