Minisuperspace Quantum Cosmology is an approach by which it possible to infer initial conditions for dynamical systems can suitably represent observable and non-observable universes. Here we discuss theories of gravity which, from various points view, extend Einstein’s General Relativity. Specifically, the Hamiltonian formalism f(R), f(T), f(G) gravity, with R, T, G being curvature, torsion Gau...

Whereas semiclassical gravity is based on the semiclassical Einstein equation with sources given by the expectation value of the stress-energy tensor of quantum fields, stochastic semiclassical gravity is based on the Einstein-Langevin equation, which has in addition sources due to the noise kernel. The noise kernel is the vacuum expectation value of the (operatorvalued) stress-energy bi-tensor...

We report bacterial growth under hypergravitational stress. Cultures of E. coli and B. subtilis were subjected to the gravitational stress (38g) and their growth curves were measured using UV-VIS spectrophotometer. Experiments were also carried out to investigate nutrient consumption under hypergravitational conditions. Our results show considerable difference between samples subjected to hyper...

This note is concerned with the study of the initial boundary value problem for systems of conservation laws from the point of view of control theory, where the initial data is fixed and the boundary data are regarded as control functions. We first consider the problem of controllability at a fixed time for genuinely nonlinear Temple class systems, and present a description of the set of attain...

Silicic calderas form during explosive volcanic eruptions when magma withdrawal triggers collapse along bounding faults. The nature of specific interactions between magmatism and tectonism in caldera-forming systems is, however, unclear. Regional stress patterns may control the location and geometry of magma reservoirs, which in turn may control the spatial and temporal development of faults. H...

The fourth derivative models for two dimensional gravity are shown to be equivalent to the special version of the nonlinear sigma models coupled to 2d quantum gravity. The reduction consists in the introduction of the auxiliary scalar fields and can be performed in an explicit way for both metric and general metric-dilaton cases. In view of this we can evaluate the structure of possible counter...

We present an analysis of a devised sample of Rotation Curves (RCs), aimed at checking the consequences of a modified f(R) gravity in galactic scales. Originally motivated by the the dark energy mystery, this theory may serve as a possibility of explaining the observed non-Keplerian profiles of galactic RCs in terms of a breakdown of the Einstein General Relativity. We show that in general the ...

The hierarchy problem in particle physics has recently been approached from a geometric point of view in different models. These approaches postulate the existence of extra dimensions with various geometric properties, to explain how the hierarchy between the apparent scale of gravity M̄P ∼ 10 GeV and the weak scale mW ∼ 100 GeV can be generated. Generally, these models predict that the effects ...

Introduction: An understanding of the sources of stress, and the expected style, orientation, and magnitudes of stress and associated strain is important for understanding the evolution of faulting on Mars and its relationship to loading, thus leading to an improved understanding of Martian geologic history and surface morphology. The Tharsis province, characterized by radial graben sets and ci...