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arXiv · hep-th/9601057

Gravitational lensing by p-branes

S. S. Gubser·A. Hashimoto·I. R. Klebanov·J. M. Maldacena
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Abstract

The scattering of R-R gauge bosons off of Dirichlet p-branes is computed to leading order in the string coupling. The results are qualitatively similar to those found in the scattering of massless NS-NS bosons: all p-branes with p >= 0 exhibit stringy properties, in particular the Regge behavior. Both the R-R and NS-NS scattering amplitudes agree in the limit of small momentum transfer with scattering off the extremal R-R charged p-brane solutions found in the low-energy supergravities. We interpret this as evidence that Dirichlet-branes are an exact world-sheet description of the extremal p-branes. The -1-brane (D-instanton) is a special object which, unlike all other Dirichlet-branes, exhibits point-like behavior. We find the R-R charged instanton solution to type IIB supergravity and confirm that the field theoretic scattering off of this solution miraculously reproduces the full stringy calculation. As an aside, we include a discussion of the entropy of non-extremal black holes in ten dimensions, produced by exciting the 0-brane. We show that, for large black holes, the entropy grows linearly with the black hole mass.

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S. S. Gubser, A. Hashimoto, I. R. Klebanov, J. M. Maldacena. 1996-04-15. Gravitational lensing by p-branes. https://doi.org/10.1016/0550-3213(96)00182-4

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