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Dynamical attractors in contracting spacetimes dominated by kinetically coupled scalar fields
Anna Ijjas, Frans Pretorius, Paul J. Steinhardt +1
We present non-perturbative numerical relativity simulations of slowly contracting spacetimes in which the scalar field driving slow contraction is coupled to a second scalar field…
Entropy, Black holes, and the New Cyclic Universe
Anna Ijjas, Paul J. Steinhardt
We track the evolution of entropy and black holes in a cyclic universe that undergoes repeated intervals of expansion followed by slow contraction and a smooth (non-singular) bounc…
The Effects of Multiple Modes and Reduced Symmetry on the Rapidity and Robustness of Slow Contraction
Anna Ijjas, Frans Pretorius, Paul J. Steinhardt +1
We demonstrate that the rapidity and robustness of slow contraction in homogenizing and flattening the universe found in simulations in which the initial conditions were restricted…
Ultralocality and Slow Contraction
Anna Ijjas, Andrew P. Sullivan, Frans Pretorius +2
We study the detailed process by which slow contraction smooths and flattens the universe using an improved numerical relativity code that accepts initial conditions with non-pertu…
Nearly scale-invariant curvature modes from entropy perturbations during graceful exit
Anna Ijjas, Roman Kolevatov
In this Letter, we describe how a spectrum of entropic perturbations generated during a period of slow contraction can source a nearly scale-invariant spectrum of curvature perturb…