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arXiv · 0903.5264

Null Energy Condition Violation and Classical Stability in the Bianchi I Metric

Irina Ya. Aref'eva·Nikolay V. Bulatov·Liudmila V. Joukovskaya·Sergey Yu. Vernov
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Abstract

The stability of isotropic cosmological solutions in the Bianchi I model is considered. We prove that the stability of isotropic solutions in the Bianchi I metric for a positive Hubble parameter follows from their stability in the Friedmann-Robertson-Walker metric. This result is applied to models inspired by string field theory, which violate the null energy condition. Examples of stable isotropic solutions are presented. We also consider the k-essence model and analyse the stability of solutions of the form $Φ(t)=t$.

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Irina Ya. Aref'eva, Nikolay V. Bulatov, Liudmila V. Joukovskaya, Sergey Yu. Vernov. 2009-10-30. Null Energy Condition Violation and Classical Stability in the Bianchi I Metric. https://doi.org/10.1103/physrevd.80.083532

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