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arXiv · 1903.10158

On almost commutative Friedmann-Lema\^itre-Robertson-Walker geometries

Andrzej Sitarz
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Abstract

We analyze the leading terms of the spectral action for a model of noncommutative geometry, which is a product of $4$-dimensional Riemannian manifold with a two-point space exploring the previously neglected case when the metrics over each sheet are different. Assuming the Friedmann-Lema\^itre-Robertson-Walker type of the metric for both sheets we obtain the action, which in addition to the the usual cosmological constant terms and the Einstein-Hilbert term involves a nonlinear interaction term. We study qualitative picture of potential consequences of such term in the basic cosmological models.

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Andrzej Sitarz. 2019-03-25. On almost commutative Friedmann-Lema\^itre-Robertson-Walker geometries. https://doi.org/10.1088/1361-6382%2Fab3d53

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