Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Prospect of the Zee model   The Zee model is one of promising models of neutrino mass generation
mechanism. However, the original Zee model is not on the framework of the
ground unification scenario, and moreover, it is recently pointed out that the
predicted value of $\sin^2 2\theta_{solar}$ must be satisfied the relation
$\sin^2 2\theta_{solar} > 0.99$. We discuss whether possible GUT versions of
the Zee model can be free from the severe constraint $\sin^2 2\theta_{solar}
>0.99$ or not. We will conclude that the following two models are promising: an
R-parity violating SUSY GUT model and an SO(10) model with a 126-plet scalar.

12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin