Entangled wavepackets in the vacuum

  • Joris KattemölleEmail author
  • Ben Freivogel
Open Access
Regular Article - Theoretical Physics


Motivated by the black hole firewall problem, we find highly entangled pairs of spatially localized modes in quantum field theory. We demonstrate that appropriately chosen wavepackets localized outside the horizon are nearly purified by ‘mirror’ modes behind the horizon. In addition, we calculate the entanglement entropy of a single localized wavepacket in the Minkowski vacuum. In all cases we study, the quantum state of the system becomes pure in the limit that the wavepackets delocalize; we quantify the trade-off between localization and purity.


Black Holes Effective Field Theories Models of Quantum Gravity 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2017

Authors and Affiliations

  1. 1.QuSoft, CWIAmsterdamThe Netherlands
  2. 2.Institute for Theoretical PhysicsUniversity of AmsterdamAmsterdamThe Netherlands
  3. 3.GRAPPAUniversity of AmsterdamAmsterdamThe Netherlands

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