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تسجيل مستخدم جديدPhenomenological model explaining Hubble Tension origin
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G.S. Bisnovatyi-Kogan
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One of the problem revealed recently in cosmology is a so-called Hubble tension (HT), which is the difference between values of the present Hubble constant, measured by observation of the universe at redshift $z lesssim 1$, and by observations of a distant universe with CMB fluctuations originated at $z sim 1100$. In this paper we suggest, that this discrepancy may be explained by deviation of the cosmological expansion from a standard Lambda-CDM %simple Friedman model of a flat universe, during the period after recombination at $z lesssim 1100$, due to action of additional variable component of a dark energy of different origin.. We suppose, that a dark matter (DM) has a common origin with a variable component of a dark energy (DEV). DE presently may have two components, one of which is the Einstein constant $Lambda$, and another, smaller component DEV ($Lambda_V$) comes from the remnants of a scalar fields responsible for inflation. Due to common origin and interconnections the densities of DEV and DM are supposed to be connected, and remain almost constant during, at least, the time after recombination, when we may approximate $rho_{DM}=alpha rho_{DEV}$. This part of the dark energy in not connected with the cosmological constant $Lambda$, but is defined by existence of scalar fields with a variable density. Taking into account the influence of DEV on the universe expansion we find the value of $alpha$ which could remove the HT problem. In order to maintain the almost constant DEV/DM energy density ratio during the time interval at $z<1100$, we suggest an existence of a wide mass DM particle distribution.
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