Implementing a Causal Measurement Scheme for Quantum Fields

by Jan Mandrysch (Austrian Academy of Sciences, Institute for Quantum Optics and Quantum Information, Vienna)

Friday 23 May 2025, 14:00 → 15:00 Europe/Budapest

Tanácsterem (III. ép.)

While measurement processes in standard quantum mechanics are well understood, the extension of these ideas to quantum field theory (QFT) remains a key challenge. In particular, ensuring that measurements respect fundamental principles such as relativistic causality is crucial. A persistent issue concerning measurements in QFT is, though, that microcausality alone is insufficient to prevent superluminal signaling. In this talk, I will present a concrete scheme for measuring real linear scalar fields, grounded in the Fewster-Verch measurement framework, which allows to model projective and Gaussian measurements and more. The approach fully respects the principles of relativistic covariance, locality, and causality, offering a robust solution to the challenges of measurement in QFT.