Quantum Discord and Quantum Computing - An Appraisal

TL;DR

This paper explores the role of quantum discord in quantum computing, especially in models like 'power of one qubit', analyzing how quantum correlations contribute to computational advantages beyond classical capabilities.

Contribution

It provides an appraisal of quantum discord's significance in quantum computational models and discusses recent findings on classical simulation boundaries.

Findings

Quantum discord delineates quantum and classical correlations.

The 'power of one qubit' model demonstrates quantum advantage.

Eastin's result links quantum discord to efficient classical simulation.

Abstract

We discuss models of computing that are beyond classical. The primary motivation is to unearth the cause of nonclassical advantages in computation. Completeness results from computational complexity theory lead to the identification of very disparate problems, and offer a kaleidoscopic view into the realm of quantum enhancements in computation. Emphasis is placed on the `power of one qubit' model, and the boundary between quantum and classical correlations as delineated by quantum discord. A recent result by Eastin on the role of this boundary in the efficient classical simulation of quantum computation is discussed. Perceived drawbacks in the interpretation of quantum discord as a relevant certificate of quantum enhancements are addressed.