Semiclassical models for uniform-density Cosmic Strings and Relativistic Stars

Astronomy and Astrophysics – Astrophysics – General Relativity and Quantum Cosmology

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

19 pages, REVTEX, no figures

Scientific paper

10.1142/S0218271897000455

In this paper we show how quantum corrections, although perturbatively small, may play an important role in the analysis of the existence of some classical models. This, in fact, appears to be the case of static, uniform--density models of the interior metric of cosmic strings and neutron stars. We consider the fourth order semiclassical equations and first look for perturbative solutions in the coupling constants $\alpha$ and $\beta$ of the quadratic curvature terms in the effective gravitational Lagrangian. We find that there is not a consistent solution; neither for strings nor for spherical stars. We then look for non--perturbative solutions and find an explicit approximate metric for the case of straight cosmic strings. We finally analyse the contribution of the non--local terms to the renormalized energy--momentum tensor and the possibility of this terms to allow for a perturbative solution. We explicitly build up a particular renormalized energy--momentum tensor to fulfill that end. These state--dependent corrections are found by simple considerations of symmetry, conservation law and trace anomaly, and are chosen to compensate for the local terms. However, they are not only ad hoc, but have to depend on $\alpha$ and $\beta$, what is not expected to first perturbative order. We then conclude that non--perturbative solutions are valuable for describing certain physical situations.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Semiclassical models for uniform-density Cosmic Strings and Relativistic Stars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Semiclassical models for uniform-density Cosmic Strings and Relativistic Stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiclassical models for uniform-density Cosmic Strings and Relativistic Stars will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-282490

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.