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arXiv · 1112.5278

Tachyon cosmology with non-vanishing minimum potential: a unified model

Huiquan Li
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Abstract

We investigate the tachyon condensation process in the effective theory with non-vanishing minimum potential and its implications to cosmology. It is shown that the tachyon condensation on an unstable three-brane described by this modified tachyon field theory leads to lower-dimensional branes (defects) forming within a stable three-brane. Thus, in the cosmological background, we can get well-behaved tachyon matter after tachyon inflation, (partially) avoiding difficulties encountered in the original tachyon cosmological models. This feature also implies that the tachyon inflated and reheated universe is followed by a Chaplygin gas dark matter and dark energy universe. Hence, such an unstable three-brane behaves quite like our universe, reproducing the key features of the whole evolutionary history of the universe and providing a unified description of inflaton, dark matter and dark energy in a very simple single-scalar field model.

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Huiquan Li. 2012-06-13. Tachyon cosmology with non-vanishing minimum potential: a unified model. https://doi.org/10.1088/1475-7516%2F2012%2F07%2F018

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