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(Non)commutative isotropization in Bianchi I with Barotropic perfect fluid and $Λ$ Cosmological

C. Ortiz·E. Mena-Barboza·M. Sabido·J. Socorro
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Abstract

We present the classical solutions to the Einstein field equations derived using the WKB-like and Hamilton procedures. The investigation is carried out in the commutative and noncommutative scenario for the Bianchi type I cosmological model coupled to barotropic perfect fluid and $λ$ Cosmological for two different gauges. Noncommutativity is achieved by modifying the symplectic structure considering that all minisuperspace variables $\rm q^i$ does not commute and by a deformation between all the minisuperspace variables. In the gauge N=1, it is possible to obtain that the anisotropic parameter $\rm β_{\pm nc}$ tend to a constant curvature for large period of time considering different values in the noncommutative parameters $θ$ and cosmological term. However, this behavior give the idea that is necessary introduce other class of matter in the models, for to have a real isotropization in the model, such as dark energy or dark matter.

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C. Ortiz, E. Mena-Barboza, M. Sabido, J. Socorro. 2007-03-20. (Non)commutative isotropization in Bianchi I with Barotropic perfect fluid and $Λ$ Cosmological. https://doi.org/10.1007/s10773-007-9557-1

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