WHAT IS NEEDED OF A TACHYON IF IT IS TO BE THE DARK ENERGY

By Edmund J.Copeland, Mohammad R.Garousi, M.Sami, S. Tsujikawa. 2004

240 citations recorded by the source corpus.

We study a dark energy scenario in the presence of a tachyon field {phi} with potential V({phi}) and a barotropic perfect fluid. The cosmological dynamics crucially depends on the asymptotic behavior of the quantity {lambda}=-M{sub p}V{sub {phi}}/V{sup 3/2}. If {lambda} is a constant, which corresponds to an inverse square potential V({phi}){proportional_to}{phi}{sup -2}, there exists one stable critical point that gives an acceleration of the Universe at late times. When {lambda}{yields}0 asymptotically, we can have a viable dark energy scenario in which the system approaches an instantaneous critical point that dynamically changes with {lambda}. If |{lambda}| approaches infinity asymptotically, the Universe does not exhibit an acceleration at late times. In this case, however, we find an interesting possibility that a transient acceleration occurs in a regime where |{lambda}| is smaller than of order unity.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/d7d5f97194d3327d4dc26a97a35c7dbfd1f5dde7

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. S. Allen
2. David Rapetti
3. R. Blandford
4. C. Boehmer
5. W. Fang
6. M. Amin
7. Edmund J. Copeland
8. Sante Carloni

In Nuclear and High Energy Physics

1. S. Allen
2. W. Fang
3. David Rapetti
4. C. Boehmer
5. M. Amin
6. Edmund J. Copeland
7. R. Blandford
8. Sante Carloni

Citations in the corpus

• Dynamical systems applied to cosmology: Dark energy and modified gravity (2017, methodology): “In this sense the cosmic dynamics of the two theories have similarities which have been noticed by several authors (see for example Copeland et al. (2005b, 2006a) and Singh (2006)).”
• A kinematical approach to dark energy studies (2006, background): “…et al. 1998; Zlatev et al. 1999; Copeland et al. 1998; Steinhardt et al. 1999; Barreiro et al. 2000), Kessence (Chiba et al. 2000; Armendariz-Picon et al. 2000, 2001), tachyon fields (Bagla et al. 2003; Copeland et al. 2005) and Chaplygin gas models (Kamenshchik et al. 2001; Bento et al. 2002).”