Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: GUTs and Exceptional Branes in F-theory - II: Experimental Predictions   We consider realizations of GUT models in F-theory. Adopting a bottom up
approach, the assumption that the dynamics of the GUT model can in principle
decouple from Planck scale physics leads to a surprisingly predictive
framework. An internal U(1) hypercharge flux Higgses the GUT group directly to
the MSSM or to a flipped GUT model, a mechanism unavailable in heterotic
models. This new ingredient automatically addresses a number of puzzles present
in traditional GUT models. The internal U(1) hyperflux allows us to solve the
doublet-triplet splitting problem, and explains the qualitative features of the
distorted GUT mass relations for lighter generations due to the Aharanov-Bohm
effect. These models typically come with nearly exact global symmetries which
prevent bare mu terms and also forbid dangerous baryon number violating
operators. Strong curvature around our brane leads to a repulsion mechanism for
Landau wave functions for neutral fields. This leads to large hierarchies of
the form exp(-c/B^(2*g)) where c and g are order one parameters and B ~
M_(GUT)/(M_(pl)*alpha_(GUT)). This effect can simultaneously generate a viably
small mu term as well as an acceptable Dirac neutrino mass on the order of 0.5
* 10^(-2 +/- 0.5) eV. In another scenario, we find a modified seesaw mechanism
which predicts that the light neutrinos have masses in the expected range while
the Majorana mass term for the heavy neutrinos is ~ 3 * 10^(12 +/- 1.5) GeV.
Communicating supersymmetry breaking to the MSSM can be elegantly realized
through gauge mediation. In one scenario, the same repulsion mechanism also
leads to messenger masses which are naturally much lighter than the GUT scale.

19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con