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Title: Anisotropic inflation from vector impurity

Abstract

We study an inflationary scenario with a vector impurity. We show that the universe undergoes anisotropic inflationary expansion due to a preferred direction determined by the vector. Using the slow roll approximation, we find a formula for determining the anisotropy of the inflationary universe. We discuss possible observable predictions of this scenario. In particular, it is stressed that primordial gravitational waves can be induced from curvature perturbations. Hence, even in low scale inflation, a sizable amount of primordial gravitational waves may be produced during inflation.

Authors:
 [1];  [2];  [3];  [4]
  1. Institute for the Physics and Mathematics of the Universe, University of Tokyo, Chiba 277-8568 (Japan)
  2. Department of Mathematics and Physics, Graduate School of Science, Osaka City University, Osaka 558-8585 (Japan)
  3. Department of Physics, Kyoto University, Kyoto 606-8501 (Japan)
  4. Department of Physics and Astrophysics, Nagoya University, Aichi 464-8602 (Japan)
Publication Date:
OSTI Identifier:
22156726
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2008; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; APPROXIMATIONS; DISTURBANCES; EXPANSION; GRAVITATIONAL WAVES; INFLATIONARY UNIVERSE

Citation Formats

Kanno, Sugumi, Kimura, Masashi, Soda, Jiro, and Yokoyama, Shuichiro, E-mail: sugumi@hep.physics.mcgill.ca, E-mail: mkimura@sci.osaka-cu.ac.jp, E-mail: jiro@tap.scphys.kyoto-u.ac.jp, E-mail: shu@a.phys.nagoya-u.ac.jp. Anisotropic inflation from vector impurity. United States: N. p., 2008. Web. doi:10.1088/1475-7516/2008/08/034.
Kanno, Sugumi, Kimura, Masashi, Soda, Jiro, & Yokoyama, Shuichiro, E-mail: sugumi@hep.physics.mcgill.ca, E-mail: mkimura@sci.osaka-cu.ac.jp, E-mail: jiro@tap.scphys.kyoto-u.ac.jp, E-mail: shu@a.phys.nagoya-u.ac.jp. Anisotropic inflation from vector impurity. United States. doi:10.1088/1475-7516/2008/08/034.
Kanno, Sugumi, Kimura, Masashi, Soda, Jiro, and Yokoyama, Shuichiro, E-mail: sugumi@hep.physics.mcgill.ca, E-mail: mkimura@sci.osaka-cu.ac.jp, E-mail: jiro@tap.scphys.kyoto-u.ac.jp, E-mail: shu@a.phys.nagoya-u.ac.jp. Fri . "Anisotropic inflation from vector impurity". United States. doi:10.1088/1475-7516/2008/08/034.
@article{osti_22156726,
title = {Anisotropic inflation from vector impurity},
author = {Kanno, Sugumi and Kimura, Masashi and Soda, Jiro and Yokoyama, Shuichiro, E-mail: sugumi@hep.physics.mcgill.ca, E-mail: mkimura@sci.osaka-cu.ac.jp, E-mail: jiro@tap.scphys.kyoto-u.ac.jp, E-mail: shu@a.phys.nagoya-u.ac.jp},
abstractNote = {We study an inflationary scenario with a vector impurity. We show that the universe undergoes anisotropic inflationary expansion due to a preferred direction determined by the vector. Using the slow roll approximation, we find a formula for determining the anisotropy of the inflationary universe. We discuss possible observable predictions of this scenario. In particular, it is stressed that primordial gravitational waves can be induced from curvature perturbations. Hence, even in low scale inflation, a sizable amount of primordial gravitational waves may be produced during inflation.},
doi = {10.1088/1475-7516/2008/08/034},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2008,
place = {United States},
year = {Fri Aug 15 00:00:00 EDT 2008},
month = {Fri Aug 15 00:00:00 EDT 2008}
}
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