Entanglement and Relativity

TL;DR

This paper reviews the relationship between quantum entanglement, non-locality, and relativity, exploring implications for different interpretations of quantum mechanics and phenomena like teleportation.

Contribution

It provides an elementary survey of how entanglement and non-locality relate to relativity, including analysis within the Everett interpretation and implications for quantum communication.

Findings

Entanglement violates Bell inequalities.

Non-locality challenges relativity assumptions.

Quantum teleportation and dense coding relate to non-locality.

Abstract

In this paper we survey, in an elementary fashion, some of the questions that arise when one considers how entanglement and relativity are related via the notion of non-locality. We begin by reviewing the role of entangled states in Bell inequality violation and question whether the associated notions of non-locality lead to problems with relativity. The use of entanglement and wavefunction collapse in Einstein's famous incompleteness argument is then considered, before we go on to see how the issue of non-locality is transformed if one considers quantum mechanics without collapse to be a complete theory, as in the Everett interpretation. The opportunity is taken to consider whether teleportation and dense coding might constitute a source of non-locality within the Everett interpretation.