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arXiv · 1712.03363

Mimetic f(T) Teleparallel gravity and cosmology

Behrouz Mirza·Fatemeh Oboudiat
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Abstract

We formulate mimetic theory in f(T) teleparallel gravity where T is torsion scalar. It is shown that the construction of the mimetic theory in the teleparallel gravity requires the vierbeins to be left unchanged and the confomal transformation performed on the Minkowski metric of the tangent space. It is further argued that the conformal degree of freedom in this teleparallel mimetic theory becomes dynamical and mimics the behavior of cold dark matter. We also show that it is possible to employ the Lagrange multipliers method to formulate the mimetic theory in an f(T) theory without any auxiliary metric. The mimetic f(T) theory is examined by the method of dynamical system and it is found that there are five fixed points representing inflation, radiation, matter, mimetic dark matter and dark energy dominated eras in the theory if some conditions are satisfied. We examined the power-law model and its phase trajectories with these conditions.

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Behrouz Mirza, Fatemeh Oboudiat. 2017-12-09. Mimetic f(T) Teleparallel gravity and cosmology. https://doi.org/10.1007/s10714-019-2576-4

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