Two studies based on data from NASA's Mars Reconnaissance Orbiter have revealed that the Red Planet once hosted vast lakes, flowing rivers and a variety of other wet environments that had the potential to support life.
We present the state of the art regarding the relation between the physics ofQuantum Black Holes and Noncommutative Geometry. We start with a review ofmodels proposed in the literature for describing deformations of GeneralRelativity in the presence of noncommutativity, seen
Our earlier results on the temperature inversion properties and theellipticisation of the finite temperature internal energy on odd spheres areextended to orbifold factors of odd spheres and then to other thermodynamicquantities, in particular to the specific heat. The behaviour under
The Dirac equation for the electron around a five-dimensional rotating blackhole with two different angular momenta is separated into purely radial andpurely angular equations. The general solution is expressed as a superpositionof solutions derived from these two decoupled ordinary differential
We study second-order cosmological perturbations in scalar-tensor models ofdark energy that satisfy local gravity constraints, including f(R) gravity. Wederive equations for matter fluctuations under a sub-horizon approximation andclarify conditions under which first-order perturbations in the scalar fieldcan be neglected relative
A Riemannian geometry of noncommutative n-dimensional surfaces is developedas a first step towards the construction of a consistent noncommutativegravitational theory. Historically, as well, Riemannian geometry was recognizedto be the underlying structure of Einstein's theory of general relativity andled to further
A theory governing the metric and matter fields in spacetime is {\it locallycausal} if the probability distribution for the fields in any region isdetermined solely by physical data in the region's past, i.e. it is independentof events at space-like separated
We consider the model where the novel interpretation of the Mach principlethat the inertial mass of a particle is formed by its interactions with allother gravitating particles inside the horizon is used. It is shown that theseinteractions result in gravitational
A new family of restricted post-Newtonian-accurate waveforms, termed TaylorEtapproximants, was recently proposed for searching gravitational wave (GW)signals from inspiraling non-spinning compact binaries having arbitrarymass-ratios. We perform detailed fitting factor (FF) studies to probe if theTaylorEt (3.5PN) signals for non-spinning comparable
In this note we study the possibility of obtaining dark energy solution in aD-brane scenario in a warped background that includes brane-position dependentcorrections for the non-perturbative superpotential. The volume modulus isstabilized at instantaneous minima of the potential. Though the model
In this work, exact solutions of static and spherically symmetric space-timesare analyzed in f(R) modified theories of gravity coupled to nonlinearelectrodynamics. Firstly, we restrict the metric fields to one degree offreedom, considering the specific case of g_{tt}=-g_{rr}^{-1}. Using the dual
The cosmological constant is the most economical candidate for dark energy.No other approach really alleviates the difficulties faced by the cosmologicalconstant because, in all other attempts to model the dark energy, one still hasto explain why the bulk cosmological constant
