ar X iv : g r - qc / 9 51 10 66 v 1 2 4 N ov 1 99 5 Scalar Field Inhomogeneous

ar X iv : g r - qc / 9 51 10 48 v 1 1 6 N ov 1 99 5 Two lectures on Two - Dimensional Gravity ∗

ar X iv : g r - qc / 9 51 10 65 v 1 2 4 N ov 1 99 5 Particle Creation in the Bell - Szekeres Spacetime Alexander Feinstein and Miguel Angel

The quantization of a real massless scalar field in a spacetime produced in a collision of two electromagnetic plane waves with constant wave fronts is considered. The background geometry in the interaction region, the Bell-Szekeres solution, is locally isometric to the con-formally flat Bertotti-Robinson universe filled with a uniform electric field. It is shown that before the waves interact ...

ar X iv : g r - qc / 0 51 10 40 v 1 8 N ov 2 00 5 Canonical gauge - invariant variables for scalar perturbations in synchronous coordinates

Under an appropriate change of the perturbation variable LifshitzKhalatnikov propagation equations for the scalar perturbation reduce to d’Alembert equation. The change of variables is based on the Darboux transform.

ar X iv : g r - qc / 0 41 10 66 v 1 1 4 N ov 2 00 4 5 - dimensional Brans - Dicke Theory and Cosmic Acceleration

We consider a 5-dimensional scalar-tensor theory which is a direct generalization of the original 4-dimensional Brans-Dicke theory to 5-dimensions. By assuming that there is a hypersurface-orthogonal spacelike Killing vector field in the underlying 5-dimensional spacetime, the theory is reduced to a 4-dimensional theory where the 4-metric is coupled with two scalar fields. The cosmological impl...

ar X iv : g r - qc / 9 71 10 36 v 1 1 1 N ov 1 99 7 Local Cosmic String In Generalised Scalar Tensor Theory

A recent investigation shows that a local gauge string with a phenomenological energy momentum tensor, as prescribed by Vilenkin, is inconsistent in Brans-Dicke theory. In this work it has been shown that such a string is consistent in a more general scalar tensor theory where ω is function of the scalar field.A set of solutions of full nonlinear Einstein's equations for interior region of such...