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arXiv · 1603.01764

Accelerated expansion of the Universe without an inflaton and resolution of the initial singularity from Group Field Theory condensates

Marco de Cesare·Mairi Sakellariadou
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Abstract

We study the expansion of the Universe using an effective Friedmann equation obtained from the dynamics of GFT (Group Field Theory) isotropic condensates. The evolution equations are classical, with quantum correction terms to the Friedmann equation given in the form of effective fluids coupled to the emergent classical background. The occurrence of a bounce, which resolves the initial spacetime singularity, is shown to be a general property of the model. A promising feature of this model is the occurrence of an era of accelerated expansion, without the need to introduce an inflaton field with an appropriately chosen potential. We discuss possible viability issues of this scenario as an alternative to inflation.

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Marco de Cesare, Mairi Sakellariadou. 2016-11-23. Accelerated expansion of the Universe without an inflaton and resolution of the initial singularity from Group Field Theory condensates. https://doi.org/10.1016/j.physletb.2016.10.051

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