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arXiv · 2312.12048

Irreversible behaviour of a gas owing to Unruh radiation

Andrew M. Steane
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Abstract

When gas molecules collide, they accelerate, and therefore encounter the Fulling-Davies-Unruh and Moore-DeWitt effects. The size of these effects is sufficient to randomize the motion of the gas molecules after about 1 nanosecond at standard temperature and pressure. Such observations show that quantum field theory modifies what is required to isolate a physical system sufficiently for its behaviour to be unitary. In practice the requirements are never satisfied exactly. Therefore the evolution of the observable universe is non-unitary and thermodynamically irreversible.

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Andrew M. Steane. 2023-12-19. Irreversible behaviour of a gas owing to Unruh radiation. https://doi.org/10.1016/j.physleta.2024.129306

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