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arXiv · 2007.05037

Cosmological Einstein-Maxwell model with $g$-essence

O. Razina·P. Tsyba·B. Meirbekov·R. Myrzakulov
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Abstract

In this paper, we study the model of the late universe with the homogeneous, isotropic and flat Friedmann-Robertson-Walker metric, where the source of the gravitational field is based on the fermion and boson field, with the Maxwell term $F_{\mu\nu}F^{\mu\nu} $ in four dimensions. The actuation of the Maxwell term for the Einstein gravity makes it possible to find new approaches to solve the problem of the observed accelerated expansion of the universe. Energy conditions have been obtained and studied. These conditions impose very simple and model-independent restrictions on the behaviour of energy density and pressure since they do not require a specific equation of state of matter. To consider the model, the energy conditions NEC, WEC, DEC are realized, and the SEC condition is violated. The boson and fermion fields are responsible for the accelerated regime at early times, but since the total pressure is tending toward zero for large times, a transition to a decelerated regime occurs. Maxwell field is crucial only in the early times.

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O. Razina, P. Tsyba, B. Meirbekov, R. Myrzakulov. 2020-07-09. Cosmological Einstein-Maxwell model with $g$-essence. https://doi.org/10.1142/s0218271819501268

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