Abstract
With the long-term goal of studying models of quantum gravity in the lab, we propose holographic teleportation protocols that can be readily executed in table-top experiments. These protocols exhibit similar behavior to that seen in the recent traversable-wormhole constructions of Gao et al. [J. High Energy Phys., 2017, 151 (2017)] and Maldacena et al. [Fortschr. Phys., 65, 1700034 (2017)]: information that is scrambled into one half of an entangled system will, following a weak coupling between the two halves, unscramble into the other half. We introduce the concept of teleportation by size to capture how the physics of operator-size growth naturally leads to information transmission. The transmission of a signal through a semiclassical holographic wormhole corresponds to a rather special property of the operator-size distribution that we call size winding. For more general systems (which may not have a clean emergent geometry), we argue that imperfect size winding is a generalization of the traversable-wormhole phenomenon. In addition, a form of signaling continues to function at high temperature and at large times for generic chaotic systems, even though it does not correspond to a signal going through a geometrical wormhole but, rather, to an interference effect involving macroscopically different emergent geometries. Finally, we outline implementations that are feasible with current technology in two experimental platforms: Rydberg-atom arrays and trapped ions.
- Received 29 September 2021
- Revised 2 November 2022
- Accepted 23 December 2022
- Corrected 18 May 2023
DOI:https://doi.org/10.1103/PRXQuantum.4.010320
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Corrections
18 May 2023
Correction: The fifth affiliation was a duplicate of the third affiliation and was removed. This change necessitated renumbering of the remaining affiliation indicators.
Popular Summary
The construction of a unified theory of quantum gravity has been one of the most intensely studied open problems in theoretical physics since the 1950s, with most ideas stemming from theoretical aspects of quantum field theory, general relativity, string theory, and loop quantum gravity. A leading candidate for such a theory is the so-called anti–de Sitter – conformal field theory (AdS-CFT) correspondence, which is a holographic theory of quantum gravity.
In this paper, we first identify a common phenomenon of chaotic quantum systems and then we use this new phenomenon to propose a class of experiments that can probe the relationship between quantum physics and holographic theories of gravity. Specifically, we describe a holographic teleportation protocol that can be readily executed in table-top experiments in near-term quantum devices. In terms of the bulk perspective in AdS-CFT, this protocol is dual to the motion of a particle traveling through a traversable wormhole connecting two disconnected space-time regions. From the boundary perspective, quantum information is first scrambled, then two different boundaries are coupled together, and then the information is unscrambled. This unscrambling process happens automatically, leading to a new type of quantum teleportation protocol that we call teleportation by size.
We argue that the transmission of a signal through a semiclassical holographic wormhole corresponds to a rather special property of the operator-size distribution that we call size winding. We also show that the protocol works beyond models that exhibit size-winding dynamics; however, in this case one may not be able to ascribe a gravitational interpretation to the phenomenon. Lastly, we outline experimentally feasible implementations of our protocol using current technology in two experimental platforms: Rydberg-atom arrays and trapped ions.