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arXiv · hep-th/9807051

Instanton Cosmology and Domain Walls from M-theory and String Theory

M. Bremer·M. J. Duff·H. Lu·C. N. Pope·K. S. Stelle
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Abstract

The recent proposal by Hawking and Turok for obtaining an open inflationary universe from singular instantons makes use of low-energy effective Lagrangians describing gravity coupled to scalars and non-propagating antisymmetric tensors. In this paper we derive some exact results for Lagrangians of this type, obtained from spherical compactifications of M-theory and string theory. In the case of the S^7 compactification of M-theory, we give a detailed discussion of the cosmological solutions. We also show that the lower-dimensional Lagrangians admit domain-wall solutions, which preserve one half of the supersymmetry, and which approach AdS spacetimes near their horizons.

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M. Bremer, M. J. Duff, H. Lu, C. N. Pope, K. S. Stelle. 1998-09-08. Instanton Cosmology and Domain Walls from M-theory and String Theory. https://doi.org/10.1016/s0550-3213(98)00764-0

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