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arXiv · 2408.03905

The gravitational quantum Otto refrigeration cycle

Nikos K. Kollas
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Abstract

We take advantage of the gravitational redshift experienced by a photon propagating in curved spacetime in order to construct a quantum Otto refrigeration cycle. Deriving a lower bound for the relative temperature between the cold and hot reservoirs at which the engine operates, we provide examples of refrigeration cycles in the presence of a uniform gravitational field as well as in the case of a gravitational field produced by a non-rotating spherically symmetric charged body, and the one obtained from the vacuum solution of Einstein's field equations in an expanding universe, as a function of the parameters which describe each spacetime.

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Nikos K. Kollas. 2024-08-07. The gravitational quantum Otto refrigeration cycle. https://arxiv.org/abs/2408.03905

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