Reversible computation and the causal structure of space-time
Abstract
Reversible algorithms play a crucial role both in classical and quantum computation. While for a classical bit the only nontrivial reversible operation is the bit-flip, nature is far more versatile in what it allows to do to a quantum bit. The reversible operations that a quantum computer can perform on a qubit are group of linear unitary transformations. However, laws of quantum mechanics prohibit implementation of anti-linear anti-unitary gates, even though they are perfectly reversible. Here we show that such a restriction on possible set of reversible operations is, remarkably, a fundamental constraint of spacetime structure. In particular, it will be shown that construction of any anti-linear anti-unitary gate will lead to violation of a fundamental causal primitive which, as we shall argue, is fundamentally different from the principle of relativistic causality.
Cite
@article{arxiv.2211.06107,
title = {Reversible computation and the causal structure of space-time},
author = {Anandamay Das Bhowmik and Preeti Parashar},
journal= {arXiv preprint arXiv:2211.06107},
year = {2022}
}