Eikonal particle scattering and dilaton gravity
Date
1997
Authors
Das, Saurya
Majumdar, Parthasarathi
Journal Title
Journal ISSN
Volume Title
Publisher
American Physical Society
Abstract
Approximating light charged pointlike particles in terms of ~nonextremal! dilatonic black holes is shown to
lead to certain pathologies in Planckian scattering in the eikonal approximation, which are traced to the
presence of a ~naked! curvature singularity in the metric of these black holes. The existence of such pathologies
is confirmed by analyzing the problem in an ‘‘external metric’’ formulation where an ultrarelativistic point
particle scatters off a dilatonic black hole geometry at large impact parameters. The maladies disappear almost
trivially upon imposing the extremal limit. Attempts to derive an effective three-dimensional ‘‘boundary’’ field
theory in the eikonal limit are stymied by four-dimensional ~bulk! terms proportional to the light-cone derivatives
of the dilaton field, leading to nontrivial mixing of electromagnetic and gravitational effects, in contrast
with the case of general relativity. An eikonal scattering amplitude, showing decoupling of these effects, is
shown to be derivable by resummation of graviton, dilaton, and photon exchange ladder diagrams in a linearized
version of the theory for an asymptotic value of the dilaton field which makes the string coupling constant
nonperturbative.
Description
Sherpa Romeo green journal. Permission to archive final published version.
Keywords
Eikonal scattering , Dilaton , Black holes
Citation
Das. S., & Majumdar, P. (1997). Eikonal particle scattering and dilaton gravity. Physical review D, 55(4), 2090-2098. http://dx.doi.org/10.1103/PhysRevD.55.2090