PREPRINT
6E7E40AD-EA55-4CB0-A6D5-F66507B3D056

Implications of Some Static Spherically Symmetric Graviton-Dilaton Solutions in Brans-Dicke and Low Energy String Theory

S. Kalyana Rama
arXiv:hep-th/9505151

Submitted on 24 May 1995

Abstract

Analysing the static, spherically symmetric graviton-dilaton solutions in low energy string and Brans-Dicke theory, we find the following. For a charge neutral point star, these theories cannot predict non trivial PPN parameters, β and γ, without introducing naked singularities. We then couple a cosmological constant Λ as in low energy string theory. We find that only in low energy string theory, a non zero Λ leads to a curvature singularity, which is much worse than a naked singularity. Requiring its absence upto a distance r implies a bound |Λ|<10102(rpc)2 in natural units. If r1Mpc then |Λ|<10114 and, if r1028cm then |Λ|<10122 in natural units.

Preprint

Comment: 11 pages. Latex File. Invited Talk presented at the XI DAE Symposium held during 21 - 28 December 1994 in Shantiniketan, India

Subjects: High Energy Physics - Theory; Astrophysics; General Relativity and Quantum Cosmology

URL: https://arxiv.org/abs/hep-th/9505151