A Lorentz-covariant collapse model for interacting quantum fields
In plain words
Collapse models are written for slow particles. Versions consistent with special relativity exist for a fixed number of distinguishable particles, but not for quantum fields, where particles are created and destroyed and continuous-collapse versions produce unlimited energy.
Precise statement
Construct a stochastic collapse dynamics for an interacting relativistic quantum field theory (e.g. $\phi^4$ or QED) that is Lorentz covariant, reduces to GRW or CSL in the nonrelativistic limit, and has a finite energy-production rate per unit volume. Tumulka's rGRWf covers non-interacting (2006) and interacting (arXiv:2002.00482, 2020) distinguishable particles with fixed $N$; relativistic CSL-type proposals need extra structure (mediating fields or smeared couplings) to avoid divergent energy production.
What would settle it
An explicit model with proofs of covariance, finite energy production and the correct nonrelativistic limit.
Status in the literature
Covariant flash collapse exists for N interacting distinguishable particles (2020); no accepted version covers variable particle number or interacting fields.