Relativistic Extension of the Unitary Retrocausal Measurement Solution

Extend the unitary, retrocausal resolution of the quantum measurement problem provided by the Fixed Point Formulation to relativistic quantum systems while maintaining compatibility with relativistic principles.

Background

The Fixed Point Formulation offers a deterministic, unitary, retrocausal account of measurement in a nonrelativistic setting, deriving the Born rule from time-symmetric structure without collapse. The paper emphasizes conceptual compatibility with general relativity and an all-at-once block universe view.

The author poses the open task of extending this resolution to relativistic systems, a necessary step for unification with quantum field theory and compatibility with Lorentz invariance.

References

I am optimistic that the ideas contained in this work can be connected to many open research questions, some of which I sketch here: Can the unitary, retrocausal resolution of the measurement problem be extended to relativistic systems?

— Many Retrocausal Worlds: A Foundation for Quantum Probability  (2510.02505 - Ridley, 2 Oct 2025) in Conclusions, final paragraph (Open research questions list)