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arXiv · 1206.2839

Gravothermal Catastrophe with a Cosmological Constant

Minos Axenides·George Georgiou·Zacharias Roupas
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Abstract

We investigate the effect of a cosmological constant on the gravothermal catastrophe in the Newtonian limit. A negative cosmological constant acts as a thermodynamic `destabilizer'. The Antonov radius gets smaller and the instability occurs, not only for negative but also for positive energy values. A positive cosmological constant acts as a `stabilizer' of the system, which, in this case, exhibits a novel `reentrant behaviour'. In addition to the Antonov radius we find a second critical radius, where an `inverse Antonov transition' occurs; a series of local entropy maxima is restored.

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Minos Axenides, George Georgiou, Zacharias Roupas. 2012-11-01. Gravothermal Catastrophe with a Cosmological Constant. https://doi.org/10.1103/physrevd.86.104005

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