0 10 80 56 v 2 1 2 Fe b 20 02 Past and future gauge in numerical relativity

- th / 0 20 20 56 v 1 1 9 Fe b 20 02 Comment on “ Spectroscopy with Random and Displaced Random Ensemble ”

/ 05 02 20 0 v 1 2 2 Fe b 20 05 Flux and Freund - Rubin Superpotentials in M - theory

We discuss the effective action for weak G2 compactifications of M-theory. The presence of fluxes acts as a source for the the axions and drives the Freund-Rubin parameter to zero. The result is a stable non-supersymmetric vacuum with a negative cosmological constant. We also give the superpotential which generates the effective potential and discuss a simple model which aims to incorporate the...

ar X iv : g r - qc / 0 20 10 59 v 2 2 8 Fe b 20 02 Gravitation and the Local Symmetry Group of Space - Time

According to general relativity, the interaction of a matter field with gravitation requires the simultaneous introduction of a tetrad field, which is a field related to translations, and a spin connection, which is a field assuming values in the Lie algebra of the Lorentz group. These two fields, however, are not independent. By analyzing the constraint between them, it is concluded that the r...

ar X iv : h ep - p h / 02 02 19 1 v 1 2 0 Fe b 20 02 DPNU - 02 - 04 Fermion Mass Hierarchy in 6 dimensional SO ( 10 ) SUSY GUT

We suggest simple models which produce the suitable fermion mass hierarchies and flavor mixing angles based on the supersymmetric SO(10) grand unified theory in 6 dimensions compactified on a T 2 /Z 2 orbifold. The gauge and Higgs fields propagate in 6 dimensions while ordinal chiral matter fields are localized in 4 dimensions. We introduce extra vector-like heavy fields in the extra dimensions...

Past and future gauge in numerical relativity

Numerical relativity describes a discrete initial value problem for general relativity. A choice of gauge involves slicing spacetime into space-like hypersurfaces. This introduces past and future gauge relative to the hypersurface of present time. Here, we propose solving the discretized Einstein equations with a choice of gauge in the future and a dynamical gauge in the past. The method is ill...