Causal measurement in quantum field theory: spacetime

Abstract

We provide a framework and explicit construction for the regularized measurement of a large class of spacetime-localized observables in bosonic quantum field theory. The measurements fully satisfy relativistic causality and causal transparency, i.e., avoid unphysical superluminal signaling. We show explicitly how the measurement of time-extended observables back-reacts on itself and induces correlations between other measurements in its causal future. Our framework is fully compositional in spacetime and extends previous results on the measurement of instantaneous observables.

40 pages, 6 figures; v2: minor corrections, changed numbering style in appendices to match published version

References in corpus (13)

• Quantum Mechanics as Quantum Measure Theory
• General boundary quantum field theory: Foundations and probability interpretation
• A detector-based measurement theory for quantum field theory
• Holomorphic Quantization of Linear Field Theory in the General Boundary Formulation
• Impossible measurements revisited
• Causal State Updates in Real Scalar Quantum Field Theory
• A local and operational framework for the foundations of physics
• Schrödinger-Feynman quantization and composition of observables in general boundary quantum field theory
• A positive formalism for quantum theory in the general boundary formulation
• Locality and General Vacua in Quantum Field Theory
• The vacuum as a Lagrangian subspace
• Quantum Field Measurements in the Fewster-Verch Framework
• Spectral decomposition of field operators and causal measurement in quantum field theory