Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutrino Mixing in a Democratic-Seesaw-Mass-Matrix Model   On the basis of a seesaw-type mass matrix model for quarks and leptons, $M_f
\simeq m_L M_F^{-1} m_R$, where $m_L\propto m_R$ are universal for $f=u,d,\nu$
and $e$ (up-quark-, down-quark-, neutrino- and charged lepton-sectors), and
$M_F$ has a form [(unit matrix)+(democratic-type matrix)], neutrino masses and
mixings are investigated. It is tried to understand a large
$\nu_\mu$-$\nu_\tau$ mixing, i.e., $\sin^2 2\theta_{23}\sim 1$, with $m_{\nu 1}
\ll m_{\nu 2} \sim m_{\nu 3}$, which has been suggested by the atmospheric
neutrino data.

9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph