An introduction to many worlds in quantum computation

TL;DR

This paper introduces the neo-Everettian many-worlds interpretation of quantum mechanics from a quantum computing perspective, defending its validity and exploring its implications for quantum computation.

Contribution

It presents a modern many-worlds interpretation tailored for quantum computation, addressing common objections and highlighting its advantages over other interpretations.

Findings

The interpretation is shown to be local and consistent.

It offers advantages for understanding quantum computation.

Objections like the 'problem of probability' are addressed and dismissed.

Abstract

The interpretation of quantum mechanics is an area of increasing interest to many working physicists. In particular, interest has come from those involved in quantum computing and information theory, as there has always been a strong foundational element in this field. This paper introduces one interpretation of quantum mechanics, a modern `many-worlds' theory, from the perspective of quantum computation. Reasons for seeking to interpret quantum mechanics are discussed, then the specific `neo-Everettian' theory is introduced and its claim as the best available interpretation defended. The main objections to the interpretation, including the so-called ``problem of probability'' are shown to fail. The local nature of the interpretation is demonstrated, and the implications of this both for the interpretation and for quantum mechanics more generally are discussed. Finally, the consequences of the theory for quantum computation are investigated, and common objections to using many worlds to describe quantum computing are answered. We find that using this particular many-worlds theory as a physical foundation for quantum computation gives several distinct advantages over other interpretations, and over not interpreting quantum theory at all.