Astronomy and Astrophysics – Astrophysics – General Relativity and Quantum Cosmology
Scientific paper
1992-10-21
Directions in general relativity, vol 1 (Cambridge U Press 1993)
Astronomy and Astrophysics
Astrophysics
General Relativity and Quantum Cosmology
13 pages
Scientific paper
We extend the argument that spacetimes generated by two timelike particles in D=3 gravity (or equivalently by parallel-moving cosmic strings in D=4) permit closed timelike curves (CTC) only at the price of Misner identifications that correspond to unphysical boundary conditions at spatial infinity and to a tachyonic center of mass. Here we analyze geometries one or both of whose sources are lightlike. We make manifest both the presence of CTC at spatial infinity if they are present at all, and the tachyonic character of the system: As the total energy surpasses its tachyonic bound, CTC first begin to form at spatial infinity, then spread to the interior as the energy increases further. We then show that, in contrast, CTC are entirely forbidden in topologically massive gravity for geometries generated by lightlike sources.
Deser Stanley
Steif Alan R.
No associations
LandOfFree
No Time Machines from Lightlike Sources in 2+1 Gravity 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 No Time Machines from Lightlike Sources in 2+1 Gravity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and No Time Machines from Lightlike Sources in 2+1 Gravity will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-705631