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  • Open Access

Toward relativistic generalization of collapse models

Anirudh Gundhi1,2,*, Lajos Diósi3,4, and Matteo Carlesso1,2

  • *Contact author: anirudh.gundhi@units.it
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Phys. Rev. A 114, 012203 – Published 9 July, 2026

DOI: https://doi.org/10.1103/g7xn-bwfs

Abstract

Spontaneous collapse models provide a possible, testable solution to the quantum measurement problem. While experiments are providing increasingly stronger bounds on their parameters, a full-fledged relativistic extension is still missing. Previous attempts have encountered different obstacles, such as violation of microcausality, infinite energy rate, and particle production from vacuum. Here, we propose a generalization of the collapse master equation that is characterized by a local field collapse operator and a non-Markovian noise with a Lorentz invariant correlation. Our construction is able to overcome previously encountered problems and has the desirable properties in the nonrelativistic limit. A specific choice of the noise correlation function is also introduced and discussed.

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Phys. Rev. A 114, 012203– Published 9 July, 2026
  • Received 16 July 2025
  • Revised 24 October 2025
  • Accepted 22 June 2026
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