The Uncertainty Relations in Quantum Mechanics

TLDR

Uncertainty has become central to quantum theory, evolving from early confusion to a fertile research area that yields new insights and measurement measures. The article aims to provide an up‑to‑date status report on uncertainty and its links to nonlocality, steering, and entanglement. The authors discuss recent controversies and highlight unresolved grey areas.

Abstract

The notion of uncertainty in the description of a physical system has assumed prodigious importance in the development of quantum theory. Overcoming the early misunderstanding and confusion, the concept grew continuously and still remains an active and fertile research field. Curious new insights and correlations are gained and developed in the process with the introduction of new 'measures' of uncertainty or indeterminacy and the development of quantum measurement theory. In this article we intend to reach a fairly uptodate status report of this yet unfurling concept and its interrelation with some distinctive quantum features like nonlocality, steering and entanglement/ inseparability. Some recent controversies are discussed and the grey areas are mentioned.