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arXiv · 1810.07385

Collapse driven by a scalar field without final singularity

Jaime M. Hernandez·Mauricio Bellini·Claudia Moreno
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Abstract

We explore a collapsing cosmology driven by a scalar field which is minimally coupled to gravity in a spatially at and spherically symmetric, isotropic and homogeneous space-time, with a variable timescale that avoids the final singularity. The equation of state that describes the collapse is $\omega=1$. We calculate the back-reaction of the space-time during the collapse and the energy density fluctuations related to this back-reaction has a spectral index $n_s = 0$, favouring short-wavelengths modes to be detected. The interesting is that the amplitude of these fluctuations increase with time when the collapse is sufficiently strong.

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Jaime M. Hernandez, Mauricio Bellini, Claudia Moreno. 2018-10-17. Collapse driven by a scalar field without final singularity. https://doi.org/10.1016/j.dark.2018.100251

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