the earth’s gravity field dedicated missions, champ, grace and goce have opened up a new era for the study of the earth’s gravity field. the missions measure different functionals on the earth’s gravitational potential which are represented in terms of the stokes coefficients or the so-called geopotential models. the mapping process of the observations into the coefficients is called recovery o...

The evolution equation of linear cosmic density perturbations in the realm of EinsteinCartan theory of gravity is obtained.The de Sitter metric fluctuation is computed in terms of the spin-torsion background density. Electronic mail: [email protected]

We present the spherical harmonic equation for the gravitational potential inside the Earth. The equation satisfies Poisson's equation and converges uniformly. It obviates the need for downward continuation of the exterior potential with its attendant convergence difficulties but of course requires some knowledge of the Earth's density distribution. Equipped with the equation, we derive the gen...

In this paper we derive a fourth-order nonlinear partial differential equation modelling the effects of suction/blowing on the evolution of the free surface of a thin viscous film on a porous base. Gravity and surface tension effects are included. The suction/blowing is modelled as an arbitrary function vn(t, r). The Lie group classification method is used to determine a firstorder quasi-linear...

Upon using some special example in the homogeneous cosmological model we develop the idea that, as a result of the arbitrariness of the factor ordering in Wheeler-DeWitt equation, gauge phases can not, in general, being completely removed from the wave functional in quantum gravity. The latter may be conveniently described by means of a remnant complex term in WDW equation depending on the fact...

In these lectures, we present geometric approach to the two-dimensional quantum gravity. It became popular since Polyakov’s discovery that first-quantized bosonic string propagating in IR can be described as theory of d free bosons coupled with the two-dimensional quantum gravity [1]. In critical dimension d = 26, the gravity decouples and Polyakov’s approach reproduces results obtained earlier...