I review the arguments in favor of/against the traditional hypothesis that the Planck, string and compactification scales are all within a couple of orders of magnitude from each other. I explain how the extreme brane-world scenario, with TeV type I scale and two large (near millimetric) transverse dimensions, creates conditions analogous to those of the energy desert and is thus naturally sing...

The paper examines within a uni…ed methodology expectational coordination in a series of economic models. The methodology views the predictions associated with the Rational Expectations Hypothesis as reasonable whenever they can be derived from more basic Common Knowledge hypothesis. The paper successively considers a simple non noisy N-dimensional model, standard models with " intrinsic " unce...

In this research, using the results of 6 tests, the effect of Carbon Fiber Reinforced Polymer (CFRP) sheets on the behavior of reinforced concrete coupling beams of shear walls is studied. First, in the experimental part of the study, four coupling beams with different reinforcements were manufactured and tested. Then, after the failure of the specimens, two of them were rehabilitated and stren...

We present a linear analysis of the vertical structure and growth of the magnetorotational instability in weakly ionised, stratified accretion discs. The method includes the effects of the magnetic coupling, the conductivity regime of the fluid and the strength of the magnetic field, which is initially vertical. The conductivity is treated as a tensor and assumed constant with height. The Hall ...

The phase diagram of the Z2 lattice Higgs model is studied without freezing out the radial excitations. Comparing the results of three meanfield models, effects of mode-mode correlations on the phase diagram are investigated. The second order end point of the first order transition line between the Higgs and the confinement phase, observed at the frozen limit of the radial mode, is shown to rea...

We consider the late-time evolution of gravitational and electromagnetic perturbations in realistic rotating Kerr spacetimes. We give a detailed analysis of the mode-coupling phenomena in rotating gravitational collapse. A consequence of this phenomena is that the late-time tail is dominated by modes which, in general, may have an angular distribution different from the original one. In additio...

It has been recently shown that solitons are fundamental classical solutions of non-commutative field theories. We reconsider this issue from the standpoint of the Hall effect and identify some solutions with known solutions in the integer Hall effect with no Zeeman coupling.

We report theoretical and experimental evidence for transverse modulational instability of two counterpropagating beams in a photorefractive medium with no external feedback. A frequency detuning is applied to one of the beams in order to drive the system to instability. We perform a linear-stability analysis that allows for detuning of the counterpropagating pump beams in addition to an additi...