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arXiv · gr-qc/0104016

Does brane cosmology have realistic principles?

D. H. Coule
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Abstract

The maximal symmetry, or Perfect Cosmological Principle(PCP), that prevents AdS type spaces from degenerating into anti-inflationary collapse is argued to be unphysical. For example, the simple requirement that brane-bulk models should be the result of having evolved from even more energetic string phenomena picks out a preferred time direction. We question whether quantum cosmological reasoning can be applied in any meaningful way to obtain, what are essentially, classical constructs . An alternative scheme is to more readily accept the PCP and allow the branes to also become eternal. A perpetually expanding and contracting brane model could be driven by the presence of charged black holes in the AdS bulk, that effectively violates the weak-energy condition as singularities are approached. This can be contrasted with the so-called Ekpyrotic universe which also closely accepts the PCP. This being broken only by occasional collisions between branes, that can then simulate a big bang cosmology.

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D. H. Coule. 2001-04-26. Does brane cosmology have realistic principles?. https://doi.org/10.1088/0264-9381%2F18%2F20%2F306

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