Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2002-12-18
Physics
High Energy Physics
High Energy Physics - Theory
27 pages, 3 figures
Scientific paper
We study string theory in supersymmetric time-dependent backgrounds. In the framework of general relativity, supersymmetry for spacetimes without flux implies the existence of a covariantly constant null vector, and a relatively simple form of the metric. As a result, the local nature of any such spacetime can be easily understood. We show that we can view any such geometry as a sequence of solutions to lower-dimensional Euclidean gravity. If we choose the lower-dimensional solutions to degenerate at some light-cone time, we obtain null singularities, which may be thought of as generalizations of the parabolic orbifold singularity. We find that in string theory, many such null singularities get repaired by $\alpha'$-corrections - in particular, by worldsheet instantons. As a consequence, the resulting string theory solutions do not suffer from any instability. Even though the CFT description of these solutions is not always valid, they can still be well understood after taking the effects of light D-branes into account; the breakdown of the worldsheet conformal field theory is purely gauge-theoretic, not involving strong gravitational effects.
Fabinger Michal
Hellerman Simeon
No associations
LandOfFree
Stringy Resolutions of Null Singularities 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 Stringy Resolutions of Null Singularities, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stringy Resolutions of Null Singularities will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-330334