Decoherence, the measurement problem, and interpretations of quantum mechanics

TL;DR

<3-5 sentence high-level summary>This paper analyzes environment-induced decoherence as a core mechanism shaping the quantum-to-classical transition and its implications for foundational problems and interpretations. It develops the decoherence program, detailing subsystem resolution, reduced density matrices, and the stability/robustness criteria that select pointer bases, while also exploring envariance and the Born rule. The work then assesses how decoherence informs a range of interpretations (Copenhagen, Everett, modal, collapse theories, Bohmian mechanics, and consistent histories), arguing that decoherence often aligns these approaches by yielding similar empirical predictions, even as it does not by itself solve the definitive-outcome problem. The discussion highlights prospects for unifying decoherence with collapse or other frameworks and outlines open conceptual challenges, such as system-environment division and the exact origin of classicality.

Abstract

Environment-induced decoherence and superselection have been a subject of intensive research over the past two decades, yet their implications for the foundational problems of quantum mechanics, most notably the quantum measurement problem, have remained a matter of great controversy. This paper is intended to clarify key features of the decoherence program, including its more recent results, and to investigate their application and consequences in the context of the main interpretive approaches of quantum mechanics.