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arXiv · 1911.04741

Dark matter candidate induced by Horndeski theory: dark matter halo and cosmological evolution

Jiaming Shi·Taishi Katsuragawa·Taotao Qiu
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Abstract

We study spherically symmetric solutions with a scalar field in the shift-symmetric subclass of the Horndeski theory. Constructing an effective energy-momentum tensor of the scalar field based on the two-fluid model, we decompose the scalar field into two components: dark matter and dark energy.We find the dark-matter fluid is pressure-less, and its distribution of energy density obeys the inverse-square law. We show the scalar field dark matter can explain the galaxy rotation curve and discuss the time evolution of the dark matter in the cosmic background.

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Jiaming Shi, Taishi Katsuragawa, Taotao Qiu. 2019-11-12. Dark matter candidate induced by Horndeski theory: dark matter halo and cosmological evolution. https://doi.org/10.1103/physrevd.101.024046

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