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arXiv · 1810.12090

SNe Ia Redshift in a Non-Adiabatic Universe

Rajendra P. Gupta
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Abstract

By relaxing the constraint of adiabatic universe used in most cosmological models, we have shown that the new approach provides a better fit to the supernovae Ia redshift data with a single parameter, the Hubble constant $H_0$, than the standard $\Lambda$CDM model with two parameters, $H_0$ and the cosmological constant $\Lambda$ related density $\Omega_{\Lambda}$. The new approach is compliant with the cosmological principle. It yields the H_0=68.28 (+- 0.53) km s-1Mpc-1 with an analytical value of the deceleration parameter q_0=-0.4. The analysis presented is for a matter only, flat universe. The cosmological constant $\Lambda$ may thus be considered as a manifestation of a non-adiabatic universe that is treated as an adiabatic universe.

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Rajendra P. Gupta. 2018-10-04. SNe Ia Redshift in a Non-Adiabatic Universe. https://doi.org/10.3390/universe4100104

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