Information transfer during the universal gravitational decoherence

TL;DR

This paper investigates how gravitational decoherence can cause information about a quantum system's position to become redundantly encoded, leading to objectivization, and explores the implications for quantum-classical transition and general relativity.

Contribution

It analyzes the information transfer process during gravitational decoherence, deriving relevant time-scales and demonstrating robustness with thermal states, linking quantum decoherence to classical objectivity.

Findings

Gravitational decoherence induces redundant information encoding.

Objectivization of position occurs on short time-scales.

The effect remains robust at finite temperatures.

Abstract

Recently Pikovski et al. have proposed in [ Pikovski I et al. 2015 Nature Phys. 11, 668] an intriguing universal decoherence mechanism, suggesting that gravitation may play a conceptually important role in the quantum-to-classical transition, albeit vanishingly small in everyday situations. Here we analyze information transfer induced by this mechanism. We show that generically on short time-scales, gravitational decoherence leads to a redundant information encoding, which results in a form of objectivization of the center-of-mass position in the gravitational field. We derive the relevant time-scales of this process, given in terms of energy dispersion and quantum Fisher information. As an example we study thermal coherent states and show certain robustness of the effect with the temperature. Finally, we draw an analogy between our objectivization mechanism and the fundamental problem of point individuation in General Relativity as emphasized by the Einstein's Hole argument.