Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Neutrino Mass Matrix - New Developments   With the recent experimental advance in our precise knowledge of the neutrino
oscillation parameters, the correct form of the 3 X 3 neutrino mass matrix is
now approximately known. I discuss how this may be obtained from symmetry
principles, using as examples the finite groups A_4 and Z_4, predicting as a
result three nearly degenerate Majorana neutrino masses in the 0.2 eV range.

24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an