Supercritical Stability, Transitions, and (Pseudo)tachyons
Abstract
Highly supercritical strings (c >> 15) with a timelike 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 latetime 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 backreaction 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 backreaction. Similarly, the copious particles produced in transitions between highly supercritical theories do not backreact significantly on the solution. We discuss these features also in a somewhat more general class of timedependent backgrounds with stable latetime asymptotics.
 Authors:
 Publication Date:
 Research Org.:
 Stanford Linear Accelerator Center (SLAC)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 896936
 Report Number(s):
 SLACPUB12243
hepth/0612031; TRN: US200705%%80
 DOE Contract Number:
 AC0276SF00515
 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; TheoryHEP,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 timelike 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 latetime 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 backreaction 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 backreaction. Similarly, the copious particles produced in transitions between highly supercritical theories do not backreact significantly on the solution. We discuss these features also in a somewhat more general class of timedependent backgrounds with stable latetime 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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