Bounds on the Speedup in Quantum signalling
Quantum Physics
2017-02-01 v4
Abstract
Given a discrete reversible dynamics, we can define a quantum dynamics, which acts on basis states like the classical one, but also allows for superpositions of them. It is a curious fact that in the quantum version, local changes in the initial state, after a single dynamical step, can sometimes can be detected much farther away than classically. Here we show that this effect is no use for generating faster signals. In a run of many steps the quantum propagation neighborhood can only increase by a constant fringe, so there is no asymptotic increase in speed.
Cite
@article{arxiv.0910.4461,
title = {Bounds on the Speedup in Quantum signalling},
author = {Pablo Arrighi and Vincent Nesme and Reinhard Werner},
journal= {arXiv preprint arXiv:0910.4461},
year = {2017}
}
Comments
22 pages, 9 figures