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arXiv · 2001.01743

The cosmological bulk flow in QCDM model: (In)consistency with $\Lambda CDM$

A. Salehi·M. Yarahmadi·S. Fathi
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Abstract

We study the bulk flow of the local universe using Type Ia supernova data by considering a class of cosmological model which is spatially flat,(FRW) space-times and contains cold dark matter and $Q$ component (QCDM models) of the fluid as a scalar field, with self interactions determined by a potential $V(Q)=V_{0}Exp(-\lambda Q)$ evolving in Universe. We use different cumulative redshift slices of the Union 2 catalogue. A maximum-likelihood analysis of peculiar velocities confirms that at low redshift $0.015 100 h^{-1}Mpc)$, they leaving an imprint on the microwave background anisotropy.

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A. Salehi, M. Yarahmadi, S. Fathi. 2020-01-06. The cosmological bulk flow in QCDM model: (In)consistency with $\Lambda CDM$. https://doi.org/10.1093/mnras/stab909

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