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Title: Supercritical Stability, Transitions, and (Pseudo)tachyons

Abstract

Highly supercritical strings (c >> 15) with a time-like linear dilaton provide a large class of solutions to string theory, in which closed string tachyon condensation is under control (and follows the worldsheet renormalization group flow). In this note we analyze the late-time stability of such backgrounds, including transitions between them. The large friction introduced by the rolling dilaton and the rapid decrease of the string coupling suppress the back-reaction of naive instabilities. In particular, although the graviton, dilaton, and other light fields have negative effective mass squared in the linear dilaton background, the decaying string coupling ensures that their condensation does not cause large back-reaction. Similarly, the copious particles produced in transitions between highly supercritical theories do not back-react significantly on the solution. We discuss these features also in a somewhat more general class of time-dependent backgrounds with stable late-time asymptotics.

Authors:
;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
896936
Report Number(s):
SLAC-PUB-12243
hep-th/0612031; TRN: US200705%%80
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review D
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; EFFECTIVE MASS; FRICTION; RENORMALIZATION; ROLLING; STABILITY; TACHYONS; Theory-HEP,HEPTH

Citation Formats

Aharony, Ofer, and Silverstein, Eva. Supercritical Stability, Transitions, and (Pseudo)tachyons. United States: N. p., 2007. Web. doi:10.1103/PhysRevD.75.046003.
Aharony, Ofer, & Silverstein, Eva. Supercritical Stability, Transitions, and (Pseudo)tachyons. United States. doi:10.1103/PhysRevD.75.046003.
Aharony, Ofer, and Silverstein, Eva. Wed . "Supercritical Stability, Transitions, and (Pseudo)tachyons". United States. doi:10.1103/PhysRevD.75.046003. https://www.osti.gov/servlets/purl/896936.
@article{osti_896936,
title = {Supercritical Stability, Transitions, and (Pseudo)tachyons},
author = {Aharony, Ofer and Silverstein, Eva},
abstractNote = {Highly supercritical strings (c >> 15) with a time-like linear dilaton provide a large class of solutions to string theory, in which closed string tachyon condensation is under control (and follows the worldsheet renormalization group flow). In this note we analyze the late-time stability of such backgrounds, including transitions between them. The large friction introduced by the rolling dilaton and the rapid decrease of the string coupling suppress the back-reaction of naive instabilities. In particular, although the graviton, dilaton, and other light fields have negative effective mass squared in the linear dilaton background, the decaying string coupling ensures that their condensation does not cause large back-reaction. Similarly, the copious particles produced in transitions between highly supercritical theories do not back-react significantly on the solution. We discuss these features also in a somewhat more general class of time-dependent backgrounds with stable late-time asymptotics.},
doi = {10.1103/PhysRevD.75.046003},
journal = {Physical Review D},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 03 00:00:00 EST 2007},
month = {Wed Jan 03 00:00:00 EST 2007}
}
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