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arXiv · 2010.13998

Nonlinear cosmological structure with ultralight bosons via modified gravity

Stefany G. Medellin-Gonzalez·L. Arturo Urena-Lopez·Alma X. Gonzalez-Morales
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Abstract

Ultra-light bosons as dark matter has become a model of major interest in Cosmology, due to the possible imprint of a distinct signature in the cosmic structure both at the linear and non-linear scales. In this work we show that the equations of motion for density perturbations for this kind of models can be written in terms of a modified gravitational potential. Taking advantage of this parallelism, we use the MG-PICOLA code originally developed for modified gravity models to evolve the density field of axion models with and without self-interaction. Our results indicate that the quantum potential adds extra suppression of power at the non-linear level, and it is even capable of smoothing any bumpy features initially present in the mass power spectrum.

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Stefany G. Medellin-Gonzalez, L. Arturo Urena-Lopez, Alma X. Gonzalez-Morales. 2020-10-27. Nonlinear cosmological structure with ultralight bosons via modified gravity. https://doi.org/10.1103/physrevd.103.083509

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