A test of the equivalence principle(s) for quantum superpositions

Patrick J. Orlando, Robert B. Mann, Kavan Modi, Felix Pollock

Research output: Contribution to journalLetterResearchpeer-review

13 Citations (Scopus)


We propose an experimental test of the quantum equivalence principle introduced by Zych and Brukner (arXiv:1502.00971), which generalises the Einstein equivalence principle to superpositions of internal energy states. We consider a harmonically trapped spin -1/2 atom in the presence of both gravity and an external magnetic field and show that when the external magnetic field is suddenly switched off, various violations of the equivalence principle would manifest as otherwise forbidden transitions. Performing such an experiment would put bounds on the various phenomenological violating parameters. We further demonstrate that the classical weak equivalence principle can be tested by suddenly putting the apparatus into free fall, effectively switching off gravity.

Original languageEnglish
Article number19LT01
Number of pages16
JournalClassical and Quantum Gravity
Issue number19
Publication statusPublished - 9 Sep 2016


  • equivalence principles
  • Newtonian gravity
  • quantum superposition of mass

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