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arXiv · 1812.08816

A new method to probe the mass density and the cosmological constant using configuration entropy

Biswajit Pandey·Biswajit Das
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Abstract

We study the evolution of the configuration entropy for different combinations of $\Omega_{m0}$ and $\Omega_{\Lambda0}$ in the flat $\Lambda$CDM universe and find that the cosmological constant plays a decisive role in controlling the dissipation of the configuration entropy. The configuration entropy dissipates at a slower rate in the models with higher value of $\Omega_{\Lambda0}$. We find that the entropy rate decays to reach a minimum and then increases with time. The minimum entropy rate occurs at an earlier time for higher value of $\Omega_{\Lambda0}$. We identify a prominent peak in the derivative of the entropy rate whose location closely coincides with the scale factor corresponding to the transition from matter to $\Lambda$ domination. We find that the peak location is insensitive to the initial conditions and only depends on the values of $\Omega_{m0}$ and $\Omega_{\Lambda0}$. We propose that measuring the evolution of the configuration entropy in the Universe and identifying the location of the peak in its second derivative would provide a new and robust method to probe the mass density and the cosmological constant.

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Biswajit Pandey, Biswajit Das. 2018-12-20. A new method to probe the mass density and the cosmological constant using configuration entropy. https://doi.org/10.1093/mnrasl%2Fslz029

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