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arXiv · 2503.17878

Non-Commutative fluid: an alternative source of cosmic acceleration

Raj Kumar Das·Arpan Krishna Mitra
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Abstract

We present a novel formulation for the Hubble parameter derived from Newtonian cosmology, incorporating non-commutative fluid dynamics through a deformed Poisson bracket structure. This approach introduces a new cosmological parameter, denoted by $\sigma$, which emerges naturally from the underlying non-commutative framework. It gives rise to a source term in the background fluid continuity equation, thereby leading to an apparent type of matter creation picture through the resulting non-conservation. Remarkably, the resulting Hubble function accounts for the observed accelerated expansion of the universe without invoking any external dark energy component or cosmological constant. Instead, the parameter $\sigma$ effectively serves as the driver of acceleration. We further examine the observational constraints on $\sigma$ using current cosmological data, including the recent Dark Energy Spectroscopic Instrument(DESI) dataset, demonstrating its viability as an alternative explanation for late-time cosmic acceleration within a non-commutative cosmological model.

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Raj Kumar Das, Arpan Krishna Mitra. 2025-03-22. Non-Commutative fluid: an alternative source of cosmic acceleration. https://doi.org/10.1016/j.aop.2026.170384

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