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Information Entropy in Cosmology

Akio Hosoya·Thomas Buchert·Masaaki Morita
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Abstract

The effective evolution of an inhomogeneous cosmological model may be described in terms of spatially averaged variables. We point out that in this context, quite naturally, a measure arises which is identical to a fluid model of the `Kullback-Leibler Relative Information Entropy', expressing the distinguishability of the local inhomogeneous mass density field from its spatial average on arbitrary compact domains. We discuss the time-evolution of `effective information' and explore some implications. We conjecture that the information content of the Universe -- measured by Relative Information Entropy of a cosmological model containing dust matter -- is increasing.

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Akio Hosoya, Thomas Buchert, Masaaki Morita. 2004-02-17. Information Entropy in Cosmology. https://doi.org/10.1103/physrevlett.92.141302

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