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Further Exact Cosmological Solutions to Higher-Order Gravity Theories

T. Clifton·John D. Barrow
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Abstract

We investigate the effect of deviations from general relativity on approach to the initial singularity by finding exact cosmological solutions to a wide class of fourth-order gravity theories. We present new anisotropic vacuum solutions of modified Kasner type and demonstrate the extent to which they are valid in the presence of non-comoving perfect-fluid matter fields. The infinite series of Mixmaster oscillations seen in general relativity will not occur in these solutions, except in unphysical cases.

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T. Clifton, John D. Barrow. 2006-01-27. Further Exact Cosmological Solutions to Higher-Order Gravity Theories. https://doi.org/10.1088/0264-9381%2F23%2F9%2F011

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