Speed Limit on the brane

Relationship between the speed limit on the brane and in the bulk is discussed. We assume that the speed of light, similar to the 4-dimensional gravitational constant, is not a primary fundamental constant but depends on the gravitational potential of the brane. This opens the way to explain the hierarchy between the Plank and Higgs scales even within the simplest 5-dimensional model.Comment: RevTeX, 2 pages, no figure

Electroweak Phase Transitions in Einstein's Static Universe

We suggest using Einstein's static universe metric for the metastable state after reheating, instead of the Friedman-Robertson-Walker spacetime. In this case strong static gravitational potential leads to the effective reduction of the Higgs vacuum expectation value, which is found to be compatible with the Standard Model first order electroweak phase transition conditions. Gravity could also increase the CP-violating effects for particles that cross the new phase bubble walls and thus is able to lead to the successful electroweak baryogenesis scenario.Comment: The published versio

Rotations in the Space of Split Octonions

The geometrical application of split octonions is considered. The modified Fano graphic, which represents products of the basis units of split octonionic, having David's Star shape, is presented. It is shown that active and passive transformations of coordinates in octonionic '8-space' are not equivalent. The group of passive transformations that leave invariant the norm of split octonions is SO(4,4), while active rotations is done by the direct product of O(3,4)-boosts and real non-compact form of the exceptional group $G_2$. In classical limit these transformations reduce to the standard Lorentz group.Comment: 10 pages, 1 figur

Octonionic Geometry

We extend vector formalism by including it in the algebra of split octonions, which we treat as the universal algebra to describe physical signals. The new geometrical interpretation of the products of octonionic basis units is presented. Eight real parameters of octonions are interpreted as the space-time coordinates, momentum and energy. In our approach the two fundamental constants, $c$ and $\hbar$, have the geometrical meaning and appear from the condition of positive definiteness of the octonion norm. We connect the property of non-associativity with the time irreversibility and fundamental probabilities in physics.Comment: 11 pages, no figure