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arXiv · 0809.1919

Tachyonization of the $\La$CDM cosmological model

Luis P. Chimento·Mónica Forte·Gilberto M. Kremer·Marlos O. Ribas
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Abstract

In this work a tachyonization of the $\Lambda$CDM model for a spatially flat Friedmann-Robertson-Walker space-time is proposed. A tachyon field and a cosmological constant are considered as the sources of the gravitational field. Starting from a stability analysis and from the exact solutions for a standard tachyon field driven by a given potential, the search for a large set of cosmological models which contain the $\Lambda$CDM model is investigated. By the use of internal transformations two new kinds of tachyon fields are derived from the standard tachyon field, namely, a complementary and a phantom tachyon fields. Numerical solutions for the three kinds of tachyon fields are determined and it is shown that the standard and complementary tachyon fields reproduces the $\Lambda$CDM model as a limiting case. The standard tachyon field can also describe a transition from an accelerated to a decelerated regime, behaving as an inflaton field at early times and as a matter field at late times. The complementary tachyon field always behaves as a matter field. The phantom tachyon field is characterized by a rapid expansion where its energy density increases with time.

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Luis P. Chimento, Mónica Forte, Gilberto M. Kremer, Marlos O. Ribas. 2008-09-11. Tachyonization of the $\La$CDM cosmological model. https://doi.org/10.1007/s10714-009-0924-5

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