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arXiv · 2006.04999

Robustness of slow contraction to cosmic initial conditions

Anna Ijjas·William G. Cook·Frans Pretorius·Paul J. Steinhardt·Elliot Y. Davies
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Abstract

We present numerical relativity simulations of cosmological scenarios in which the universe is smoothed and flattened by undergoing a phase of slow contraction and test their sensitivity to a wide range of initial conditions. Our numerical scheme enables the variation of all freely specifiable physical quantities that characterize the initial spatial hypersurface, such as the initial shear and spatial curvature contributions as well as the initial field and velocity distributions of the scalar that drives the cosmological evolution. In particular, we include initial conditions that are far outside the perturbative regime of the well-known attractor scaling solution. We complement our numerical results by analytically performing a complete dynamical systems analysis and show that the two approaches yield consistent results.

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Anna Ijjas, William G. Cook, Frans Pretorius, Paul J. Steinhardt, Elliot Y. Davies. 2020-06-09. Robustness of slow contraction to cosmic initial conditions. https://doi.org/10.1088/1475-7516%2F2020%2F08%2F030

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