Is non-particle dark matter equation of state parameter evolving with time?

Souvik Ghose; Arunabha Bhadra

doi:10.1140/epjc/s10052-021-09490-1

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arXiv · 2108.04686

Is non-particle dark matter equation of state parameter evolving with time?

Souvik Ghose·Arunabha Bhadra

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Abstract

Recently, the so-called Hubble Tension, i.e. the mismatch between the local and the cosmological measurements of the Hubble parameter, has been resolved when non-particle dark matter is considered which has a negative equation of state parameter ($\omega \approx -0.01$). We investigate if such a candidate can successfully describe the galactic flat rotation curves. It is found that the flat rotation curve feature puts a stringent constraint on the dark matter equation of state parameter $\omega$ and $\omega \approx -0.01$ is not consistent with flat rotational curves, observed around the galaxies. However, a dynamic $\omega$ of non-particle dark matter may overcome the Hubble tension without affecting the flat rotation curve feature.

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Souvik Ghose, Arunabha Bhadra. 2021-07-26. Is non-particle dark matter equation of state parameter evolving with time?. https://doi.org/10.1140/epjc%2Fs10052-021-09490-1

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