Assisted dark energy

Junko Ohashi, Shinji Tsujikawa

Research output: Contribution to conferencePaperpeer-review


We study cosmological dynamics of a multi-field system for a general Lagrangian density having scaling solutions. This allows the possibility that scaling radiation and matter eras are followed by a late-time cosmic acceleration through an assisted inflation mechanism. Using the bound coming from Big-Bang-Nucleosynthesis (BBN) and the condition under which each field cannot drive inflation as a single component of the universe, we find the following features: (i) a transient or eternal cosmic acceleration can be realized after the scaling matter era, (ii) a "thawing" property of assisting scalar fields is crucial to determine the evolution of the field equation of state wφ, and (iii) the field equation of state today can be consistent with the observational bound wφin the presence of multiple scalar fields.

Original languageEnglish
Number of pages4
Publication statusPublished - 2009
Externally publishedYes
Event19th Workshop on General Relativity and Gravitation in Japan, JGRG 2009 - Tokyo, Japan
Duration: 2009 Nov 302009 Dec 4


Conference19th Workshop on General Relativity and Gravitation in Japan, JGRG 2009

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics


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