Universal decoherence due to gravitational time dilation

Author(s)
Igor Pikovski, Magdalena Zych, Fabio Costa, Caslav Brukner
Abstract

The physics of low-energy quantum systems is usually studied without explicit consideration of the background spacetime. Phenomena inherent to quantum theory in curved spacetime, such as Hawking radiation, are typically assumed to be relevant only for extreme physical conditions: at high energies and in strong gravitational fields. Here we consider low-energy quantum mechanics in the presence of gravitational time dilation and show that the latter leads to the decoherence of quantum superpositions. Time dilation induces a universal coupling between the internal degrees of freedom and the centre of mass of a composite particle. The resulting correlations lead to decoherence in the particle position, even without any external environment. We also show that the weak time dilation on Earth is already sufficient to affect micrometre-scale objects. Gravity can therefore account for the emergence of classicality and this effect could in principle be tested in future matter-wave experiments.

Organisation(s)
Quantum Optics, Quantum Nanophysics and Quantum Information
External organisation(s)
Österreichische Akademie der Wissenschaften (ÖAW), Harvard University, University of Queensland
Journal
Nature Physics
Volume
11
Pages
668–672
No. of pages
5
ISSN
1745-2473
DOI
https://doi.org/10.1038/nphys3366
Publication date
08-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103025 Quantum mechanics
ASJC Scopus subject areas
General Physics and Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/986ccb45-390e-4a99-8062-ee5441a0ff56