Quantum Paradox of Choice: More Freedom Makes Summoning a Quantum State Harder

Authors

Emily Adlam, Chapman UniversityFollow
Adrian Kent, University of Cambridge

Document Type

Article

Publication Date

6-21-2016

Abstract

The properties of quantum information in space-time can be investigated by studying operational tasks, such as “summoning,” in which an unknown quantum state is supplied at one point and a call is made at another for it to be returned at a third. Hayden and May [arXiv:1210.0913] recently proved necessary and sufficient conditions for guaranteeing successful return of a summoned state for finite sets of call and return points when there is a guarantee of at most one summons. We prove necessary and sufficient conditions when there may be several possible summonses and complying with any one constitutes success, and we demonstrate the existence of an apparent paradox: The extra freedom makes it strictly harder to complete the summoning task. This result has practical applications for distributed quantum computing and cryptography and implications for our understanding of relativistic quantum information and its localization in space-time.

Comments

This article was originally published in Physical Review A, volume 93, in 2016. https://doi.org/10.1103/PhysRevA.93.062327

Recommended Citation

E. Adlam and A. Kent, Quantum paradox of choice: More freedom makes summoning a quantum state harder, Phys. Rev. A 93, 062327 (2015). https://doi.org/10.1103/PhysRevA.93.062327

Peer Reviewed

1

Copyright

American Physical Society