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## Context

Lately, I have been reading a scholarly paper entitled An Introduction to Quantum Computing for Non-Physicists which discusses the EPR Paradox.

The paper states that:

Einstein, Podolsky and Rosen proposed a gedanken experiment that uses entangled particles in a manner that seemed to violate fundamental principles of relativity.

It concludes that the paradox is resolved as the symmetry shown by changing observers indicates that they cannot use their EPR pair to communicate faster than the speed of light. However, the paper fails to adequately explain what an EPR pair is used for and does not even define the term. The best definition I could find is referenced to in the Wikipedia article, Bell state.

An EPR pair is a pair of qubits (or quantum bits) that are in a Bell state together.

This definition doesn't provide much detail beyond the basics of what an EPR pair is.

## The Question

How are EPR Pairs used in quantum computing?

The question is rather vague and open-ended. The answer is that Bell states are everything and nothing - you can formulate a quantum computation almost entirely in terms of Bell pairs (see measurement-based quantum computation, and some of the ways that a cluster state can be generated), or not use them at all (e.g. computation by Hamiltonian evolution), and everything in between.

– DaftWullie – 2018-04-11T07:00:31.483