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Title: Nonlocal String Tachyon as a Model for Cosmological Dark Energy

Abstract

There are many different phenomenological models describing the cosmological dark energy and accelerating Universe by choosing adjustable functions. In this paper we consider a specific model of scalar tachyon field which is derived from the NSR string field theory and study its cosmological applications. We find that in the effective field theory approximation the equation of state parameter w < -1, i.e. one has a phantom Universe. It is shown that due to nonlocal effects there is no quantum instability that the usual phantom models suffer from. Moreover due to a flip effect of the potential the Universe does not enter to a future singularity.

Authors:
 [1]
  1. Steklov Mathematical Institute, Russian Academy of Sciences, Gubkin st. 8, Moscow, 119991 (Russian Federation)
Publication Date:
OSTI Identifier:
20800059
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 826; Journal Issue: 1; Conference: 2. international conference on p-adic mathematical physics, Belgrade (Serbia and Montenegro), 15-21 Sep 2005; Other Information: DOI: 10.1063/1.2193132; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; APPROXIMATIONS; COSMOLOGY; EQUATIONS OF STATE; INSTABILITY; NONLUMINOUS MATTER; QUANTUM FIELD THEORY; SCALARS; SINGULARITY; STRING MODELS; TACHYONS; UNIVERSE

Citation Formats

Aref'eva, Irina Ya. Nonlocal String Tachyon as a Model for Cosmological Dark Energy. United States: N. p., 2006. Web. doi:10.1063/1.2193132.
Aref'eva, Irina Ya. Nonlocal String Tachyon as a Model for Cosmological Dark Energy. United States. doi:10.1063/1.2193132.
Aref'eva, Irina Ya. Wed . "Nonlocal String Tachyon as a Model for Cosmological Dark Energy". United States. doi:10.1063/1.2193132.
@article{osti_20800059,
title = {Nonlocal String Tachyon as a Model for Cosmological Dark Energy},
author = {Aref'eva, Irina Ya.},
abstractNote = {There are many different phenomenological models describing the cosmological dark energy and accelerating Universe by choosing adjustable functions. In this paper we consider a specific model of scalar tachyon field which is derived from the NSR string field theory and study its cosmological applications. We find that in the effective field theory approximation the equation of state parameter w < -1, i.e. one has a phantom Universe. It is shown that due to nonlocal effects there is no quantum instability that the usual phantom models suffer from. Moreover due to a flip effect of the potential the Universe does not enter to a future singularity.},
doi = {10.1063/1.2193132},
journal = {AIP Conference Proceedings},
number = 1,
volume = 826,
place = {United States},
year = {Wed Mar 29 00:00:00 EST 2006},
month = {Wed Mar 29 00:00:00 EST 2006}
}
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