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arXiv · gr-qc/0509085

Exact cosmological solutions of scale-invariant gravity theories

John D. Barrow·T. Clifton
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Abstract

We have found new anisotropic vacuum solutions for the scale-invariant gravity theories which generalise Einstein's general relativity to a theory derived from the Lagrangian $R^{1+δ}$. These solutions are expanding universes of Kasner form with an initial spacetime singularity at $t=0 $ and exist for $-1/2<δ<1/4$ but possess different Kasner index relations to the classic Kasner solution of general relativity to which they reduce when $δ=0$. These solutions are unperturbed by the introduction of non-comoving perfect-fluid matter motions if $p<ρ$ on approach to the singularity and should not exhibit an infinite sequence of chaotic Mixmaster oscillations when $δ>0$.

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John D. Barrow, T. Clifton. 2005-09-21. Exact cosmological solutions of scale-invariant gravity theories. https://doi.org/10.1088/0264-9381%2F23%2F1%2Fl01

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