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Title: Can quantum probes satisfy the weak equivalence principle?

Abstract

We address the question whether quantum probes in a gravitational field can be considered as test particles obeying the weak equivalence principle (WEP). A formulation of the WEP is proposed which applies also in the quantum regime, while maintaining the physical content of its classical counterpart. Such formulation requires the introduction of a gravitational field not to modify the Fisher information about the mass of a freely-falling probe, extractable through measurements of its position. We discover that, while in a uniform field quantum probes satisfy our formulation of the WEP exactly, gravity gradients can encode nontrivial information about the particle’s mass in its wavefunction, leading to violations of the WEP. - Highlights: • Can quantum probes under gravity be approximated as test-bodies? • A formulation of the weak equivalence principle for quantum probes is proposed. • Quantum probes are found to violate it as a matter of principle.

Authors:
 [1];  [1];  [2]
  1. Quantum Technology Lab, Dipartimento di Fisica, Università degli Studi di Milano, I-20133 Milano (Italy)
  2. (Italy)
Publication Date:
OSTI Identifier:
22617505
Resource Type:
Journal Article
Resource Relation:
Journal Name: Annals of Physics; Journal Volume: 380; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; EQUIVALENCE PRINCIPLE; GRAVITATIONAL FIELDS; QUANTUM MECHANICS; WAVE FUNCTIONS

Citation Formats

Seveso, Luigi, E-mail: luigi.seveso@unimi.it, Paris, Matteo G.A., and INFN, Sezione di Milano, I-20133 Milano. Can quantum probes satisfy the weak equivalence principle?. United States: N. p., 2017. Web. doi:10.1016/J.AOP.2017.03.021.
Seveso, Luigi, E-mail: luigi.seveso@unimi.it, Paris, Matteo G.A., & INFN, Sezione di Milano, I-20133 Milano. Can quantum probes satisfy the weak equivalence principle?. United States. doi:10.1016/J.AOP.2017.03.021.
Seveso, Luigi, E-mail: luigi.seveso@unimi.it, Paris, Matteo G.A., and INFN, Sezione di Milano, I-20133 Milano. Mon . "Can quantum probes satisfy the weak equivalence principle?". United States. doi:10.1016/J.AOP.2017.03.021.
@article{osti_22617505,
title = {Can quantum probes satisfy the weak equivalence principle?},
author = {Seveso, Luigi, E-mail: luigi.seveso@unimi.it and Paris, Matteo G.A. and INFN, Sezione di Milano, I-20133 Milano},
abstractNote = {We address the question whether quantum probes in a gravitational field can be considered as test particles obeying the weak equivalence principle (WEP). A formulation of the WEP is proposed which applies also in the quantum regime, while maintaining the physical content of its classical counterpart. Such formulation requires the introduction of a gravitational field not to modify the Fisher information about the mass of a freely-falling probe, extractable through measurements of its position. We discover that, while in a uniform field quantum probes satisfy our formulation of the WEP exactly, gravity gradients can encode nontrivial information about the particle’s mass in its wavefunction, leading to violations of the WEP. - Highlights: • Can quantum probes under gravity be approximated as test-bodies? • A formulation of the weak equivalence principle for quantum probes is proposed. • Quantum probes are found to violate it as a matter of principle.},
doi = {10.1016/J.AOP.2017.03.021},
journal = {Annals of Physics},
number = ,
volume = 380,
place = {United States},
year = {Mon May 15 00:00:00 EDT 2017},
month = {Mon May 15 00:00:00 EDT 2017}
}
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