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Friedmann Robertson-Walker model in generalised metric space-time with weak anisotropy

P. C. Stavrinos·A. P. Kouretsis·M. Stathakopoulos
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Abstract

A generalized model of space-time is given, taking into consideration the anisotropic structure of fields which are depended on the position and the direction (velocity).In this framework a generalized FRW-metric the Raychaudhouri and Friedmann equations are studied.A long range vector field of cosmological origin is considered in relation to the physical geometry of space-time in which Cartan connection has a fundamental role.The generalised Friedmann equations are produced including anisotropic terms.The variation of anisotropy $z_t$ is expressed in terms of the Cartan torsion tensor of the Finslerian space-time.A possible estimation of the anisotropic parameter $z_t$ can be achieved with the aid of the de-Sitter model of the empty flat universe with weak anisotropy. Finally a physical generalisation for the model of inflation is also studied.

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P. C. Stavrinos, A. P. Kouretsis, M. Stathakopoulos. 2007-10-22. Friedmann Robertson-Walker model in generalised metric space-time with weak anisotropy. https://doi.org/10.1007/s10714-007-0540-1

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