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arXiv · 2208.11196

A Universal Constraint on Computational Rates in Physical Systems

Hannah Earley
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Abstract

Conventional computing has many sources of heat dissipation, but one of these--the Landauer limit--poses a fundamental lower bound of 1 bit of entropy per bit erased. 'Reversible Computing' avoids this source of dissipation, but is dissipationless computation possible? In this paper, a general proof is given for open quantum systems showing that a computer thermally coupled to its environment will necessarily dissipate entropy (and hence heat). Specifically, a lower bound is obtained that corresponds to the adiabatic regime, in which the amount of entropy dissipated per computational operation is proportional to the rate of computation.

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Hannah Earley. 2022-08-23. A Universal Constraint on Computational Rates in Physical Systems. https://arxiv.org/abs/2208.11196

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