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arXiv · 2502.03256

Matter Creation Cosmologies and Accelerated Expansion

Sudip Halder·Jaume de Haro·Supriya Pan·Tapan Saha·Subenoy Chakraborty
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Abstract

Non-conservation of dark matter can lead to late-time cosmic acceleration. This mechanism is known as the matter creation theory and this replaces the need of dark energy and modified gravity theories. We consider a two-fluid system consisting of a cold dark matter and a second fluid with constant barotropic equation of state. We performed detailed investigations of such cosmologies using the powerful techniques of qualitative analysis of dynamical systems. Considering a wide variety of the creation rates, we examine the phase space analysis of the individual scenario. According to our analyses, these scenarios predict decelerating unstable dark matter (or second fluid) dominated critical points, accelerating attractors dominated either by dark matter or the second fluid, accelerating scaling attractors in which dark matter and the second fluid co-exist. The regime of late-time accelerating expansion can be classified as either quintessence, phantom or driven by a cosmological constant. This huge variety of critical points makes these scenarios phenomenologically rich, and naturally suggests that such scenarios can be viewed as viable and potential alternatives to the mainstream cosmological models.

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Sudip Halder, Jaume de Haro, Supriya Pan, Tapan Saha, Subenoy Chakraborty. 2025-02-05. Matter Creation Cosmologies and Accelerated Expansion. https://doi.org/10.1007/s10714-025-03499-7

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