Self-gravitating field configurations: The role of the energy-momentum trace

0Citations
Citations of this article
5Readers
Mendeley users who have this article in their library.

Abstract

Static spherically-symmetric matter distributions whose energy-momentum tensor is characterized by a non-negative trace are studied analytically within the framework of general relativity. We prove that such field configurations are necessarily highly relativistic objects. In particular, for matter fields with T≥α{dot operator}ρ≥0 (here T and ρ are respectively the trace of the energy-momentum tensor and the energy density of the fields, and α is a non-negative constant), we obtain the lower bound maxr {2m(r)/r}>(2+2α)/(3+2α) on the compactness (mass-to-radius ratio) of regular field configurations. In addition, we prove that these compact objects necessarily possess (at least) two photon-spheres, one of which exhibits stable trapping of null geodesics. The presence of stable photon-spheres in the corresponding curved spacetimes indicates that these compact objects may be nonlinearly unstable. We therefore conjecture that a negative trace of the energy-momentum tensor is a necessary condition for the existence of stable, soliton-like (regular) field configurations in general relativity.

Cite

CITATION STYLE

APA

Hod, S. (2014). Self-gravitating field configurations: The role of the energy-momentum trace. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 739, 383–386. https://doi.org/10.1016/j.physletb.2014.11.019

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free