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Title: New solutions with accelerated expansion in string theory

Abstract

We present concrete solutions with accelerated expansion in string theory, requiring a small, tractable list of stress energy sources. We explain how this construction (and others in progress) evades previous no go theorems for simple accelerating solutions. Our solutions respect an approximate scaling symmetry and realize discrete sequences of values for the equation of state, including one with an accumulation point at w = –1 and another accumulating near w = –1/3 from below. In another class of models, a density of defects generates scaling solutions with accelerated expansion. Here, we briefly discuss potential applications to dark energy phenomenology, and to holography for cosmology.

Authors:
 [1];  [1];  [2];  [1]
  1. Stanford Univ., Stanford, CA (United States)
  2. Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States); Kavli Institute for Particle Astrophysics and Cosmology, Stanford, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
National Science Foundation (NSF); USDOE Office of Science (SC)
OSTI Identifier:
1120138
Report Number(s):
SLAC-PUB-15800
Journal ID: ISSN 1029-8479; arXiv:1310.5297
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2014; Journal Issue: 12; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Theory-HEP; HEPTH; ASTRO; flux compactifications; superstring vacua; dS vacua in string theory

Citation Formats

Dodelson, Matthew, Dong, Xi, Silverstein, Eva, and Torroba, Gonzalo. New solutions with accelerated expansion in string theory. United States: N. p., 2014. Web. doi:10.1007/JHEP12(2014)050.
Dodelson, Matthew, Dong, Xi, Silverstein, Eva, & Torroba, Gonzalo. New solutions with accelerated expansion in string theory. United States. doi:10.1007/JHEP12(2014)050.
Dodelson, Matthew, Dong, Xi, Silverstein, Eva, and Torroba, Gonzalo. Fri . "New solutions with accelerated expansion in string theory". United States. doi:10.1007/JHEP12(2014)050. https://www.osti.gov/servlets/purl/1120138.
@article{osti_1120138,
title = {New solutions with accelerated expansion in string theory},
author = {Dodelson, Matthew and Dong, Xi and Silverstein, Eva and Torroba, Gonzalo},
abstractNote = {We present concrete solutions with accelerated expansion in string theory, requiring a small, tractable list of stress energy sources. We explain how this construction (and others in progress) evades previous no go theorems for simple accelerating solutions. Our solutions respect an approximate scaling symmetry and realize discrete sequences of values for the equation of state, including one with an accumulation point at w = –1 and another accumulating near w = –1/3 from below. In another class of models, a density of defects generates scaling solutions with accelerated expansion. Here, we briefly discuss potential applications to dark energy phenomenology, and to holography for cosmology.},
doi = {10.1007/JHEP12(2014)050},
journal = {Journal of High Energy Physics (Online)},
number = 12,
volume = 2014,
place = {United States},
year = {Fri Dec 05 00:00:00 EST 2014},
month = {Fri Dec 05 00:00:00 EST 2014}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 4works
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