U–duality Covariant M–theory Cosmology
نویسنده
چکیده
A manifestly U–duality covariant approach to M–theory cosmology is developed and applied to cosmologies in dimensions D = 4, 5. Cosmological properties such as expansion powers and Hubble parameters turn out to be U–duality invariant in certain asymptotic regions. U–duality transformations acting on cosmological solutions, on the other hand, shift the transition time between two asymptotic regions and determine the details of the transition. Moreover, in D = 5, we show that U–duality can map expanding negative and positive branch solutions into each other. Supported by Deutsche Forschungsgemeinschaft (DFG) and Nato Collaborative Research Grant CRG. 940784. Supported in part by a Senior Alexander von Humboldt Award
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