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arXiv · 1406.5896

On the Creation of the Universe via Ekpyrotic Instantons

Lorenzo Battarra·Jean-Luc Lehners
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Abstract

We present a new class of complex instantons in the context of ekpyrotic cosmological theories. These instantons, which satisfy the "no-boundary" boundary conditions, describe the emergence of a classical, contracting universe out of nothing. The ekpyrotic attractor is essential in guaranteeing an evolution towards a real, Lorentzian history of the universe. In the context of the no-boundary proposal, the relative probability for such ekpyrotic histories compared to inflationary ones is very high -- in fact, assuming a bounce can be incorporated, these new instantons currently describe the most likely origin of the universe.

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Lorenzo Battarra, Jean-Luc Lehners. 2014-06-23. On the Creation of the Universe via Ekpyrotic Instantons. https://doi.org/10.1016/j.physletb.2015.01.028

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