RT Journal Article
T1 A detector-based measurement theory for quantum field theory
A1 Polo Gómez, José
A1 Garay Elizondo, Luis Javier
A1 Martín Martínez, Eduardo
AB We propose a measurement theory for quantum fields based on measurements made with localized nonrelativistic systems that couple covariantly to quantum fields (like the Unruh-DeWitt detector). Concretely, we analyze the positive operator-valued measure induced on the field when an idealized measurement is carried out on the detector after it coupled to the field. Using an information-theoretic approach, we provide a relativistic analogue to the quantum-mechanical Luders update rule to update the field state following the measurement on the detector. We argue that this proposal has all the desirable characteristics of a proper measurement theory. In particular it does not suffer from the "impossible measurements" problem pointed out by Rafael Sorkin in the 1990s which shows that idealized measurements cannot be used in quantum field theory.
PB American Physical Society
SN 2470-0010
YR 2022
FD 2022-03-02
LK https://hdl.handle.net/20.500.14352/115113
UL https://hdl.handle.net/20.500.14352/115113
LA eng
NO J. Polo-Gómez, L. J. Garay, and E. Martín-Martínez, A detector-based measurement theory for quantum field theory, Phys. Rev. D 105, 065003 (2022).
NO ID 100010434, with fellowship code LCF/BQ/AA20/11820043
NO Fundación La Caixa
NO Ministerio de Ciencia e Innovación (España)
NO Agencia Estatal de Investigación (España)
NO Natural Sciences and Engineering Research Council  (Canada)
DS Docta Complutense
RD 12 abr 2025