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One-way Functions In Reversible Computations

H. F. Chau·H. -K. Lo
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Abstract

One-way functions are used in modern cryto-systems as doortraps because their inverse functions are supposed to be difficult to compute. Nonetheless with the discovery of reversible computation, it seems that one may break a one-way function by running a reversible computer backward. Here, we argue that reversible computation alone poses no threat to the existence of one-way functions because of the generation of ``garbage bits'' during computations. Consequently, we prove a necessary and sufficient condition for a one-to-one function to be a one-way in terms of the growth rate of the total number of possible garbage bit configurations with the input size.

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H. F. Chau, H. -K. Lo. 1996-12-01. One-way Functions In Reversible Computations. https://arxiv.org/abs/quant-ph/9506012

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