A theorem providing a characterisation of Schwarzschildean initial data sets on slices with an asymptotically Euclidean end is proved. This characterisation is based on the proportionality of the Weyl tensor and its D’Alambertian that holds for some vacuum Petrov Type D spacetimes (e.g. the Schwarzschild spacetime, the C-metric, but not the Kerr solution). The 3+1 decomposition of this proporti...

A method for calculating special grid placement for three-point schemes which yields exponential superconvergence of the Neumann to Dirichlet map has been suggested earlier. Here we show that such a grid placement can yield impedance which is equivalent to that of a spectral Galerkin method, or more generally to that of a spectral Galerkin-Petrov method. In fact we show that for every stable Ga...

An adaptive mesh refuiement scheme and data shucture has been developed in conjunction with a streamline upwind Petrov-Galerkin finite element formulation for anaiysis of the semiconductor device equations. The nonlinear elecaostatic potential equation and convection dorninated camier current continuity equations are iteratively decoupled in the solution algorithm. Incremental continuation is e...

Using the directly derived non-hyper singular integral equations for displacement gradients [as in Okada, Rajiyah, and Atluri (1989a)], simple and straightforward derivations of weakly singular traction BIE’s for solids undergoing small deformations are presented. A large number of “intrinsic properties” of the fundamental solutions in elasticity are developed, and are used in rendering the tBI...

In this work, we derive a goal-oriented a posteriori error estimator for the error due to time-discretization of nonlinear parabolic partial differential equations by the fractional step theta method. This time-stepping scheme is assembled by three steps of the general theta method, that also unifies simple schemes like forward and backward Euler as well as the Crank–Nicolson method. Further, b...

A meshless local Petrov-Galerkin (MLPG) method is applied to solve problems of Reissner-Mindlin shells under thermal loading. Both stationary and thermal shock loads are analyzed here. Functionally graded materials with a continuous variation of properties in the shell thickness direction are considered here. A weak formulation for the set of governing equations in the Reissner-Mindlin theory i...

We deal with the numerical solution of time-dependent convection-diffusion-reaction equations. We combine the local projection stabilization method for the space discretization with two different time discretization schemes: the continuous Galerkin-Petrov (cGP) method and the discontinuous Galerkin (dG) method of polynomial of degree k. We establish the optimal error estimates and present numer...

In general, geometries of Petrov type II do not admit symmetries in terms Killing vectors or spinors. We introduce a weaker form equations which solutions. particular, there is an analog the Penrose-Walker spinor. Some its properties, including associated conservation laws, are discussed. Perturbations Einstein complex scalar Debye potential yield solutions to linearized equations. The Weyl ten...