Intrinsic and Fundamental Decoherence: Issues and Problems

TL;DR

This paper critically examines the concept of gravity-induced intrinsic decoherence in quantum mechanics, analyzing various approaches and clarifying foundational issues related to time, uncertainty, and fluctuations.

Contribution

It provides a detailed critique of existing models linking gravity and decoherence, highlighting conceptual issues and clarifying assumptions involved.

Findings

Identifies key conceptual problems in gravity-induced decoherence models

Critiques stochastic and clock fluctuation approaches to intrinsic decoherence

Clarifies the role of time and uncertainties in quantum gravity contexts

Abstract

We investigate the meaning of gravity-induced decoherence in quantum theory, known as `intrinsic' or `fundamental' decoherence in the literature. We explore a range of issues relevant to this problem, including the meaning of modified uncertainty relations, the interpretations of the Planck scale, the distinction between quantum and stochastic fluctuations and the role of the time variable in quantum mechanics. We examine the specific physical assumptions that enter into different approaches to the subject. In particular, we critique two representative approaches that identify time fluctuations as the origin of intrinsic or fundamental decoherence: one that models the fluctuations by stochastic process and one that purports to derive decoherence from the quantum fluctuations of real clocks.