Das, A and Gupta, Shashikant and Saini, Tarun Deep and Kar, Sayan (2005) Cosmology with decaying tachyon matter. In: Physical Review D, 72 (4).
We investigate the case of a homogeneous tachyon field coupled to gravity in a spatially flat Friedmann-Robertson-Walker spacetime.Assuming the field evolution to be exponentially decaying with time we solve the field equations and show that, under certain conditions, the scale factor represents an accelerating universe, following a phase of decelerated expansion. We make use of a model of dark energy (withp=-rho) and dark matter (p=0) where a single scalar field (tachyon) governs the dynamics of both the dark components. We show that this model fits the current supernova data as well as the canonical Lambda CDM model. We give the bounds on the parameters allowed by the current data.
|Item Type:||Journal Article|
|Additional Information:||Copyright for this article belongs to American Physical Society.|
|Department/Centre:||Division of Physical & Mathematical Sciences > Physics|
|Date Deposited:||06 Oct 2005|
|Last Modified:||19 Sep 2010 04:20|
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