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arXiv · 2607.17920

Sensing relativistic quantum fields with minimally perturbing local measurements

F. Daem·L. Ballesteros Ferraz·A. Zampeli·A. Matzkin
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Abstract

We develop a framework for minimally perturbing local measurements in relativistic quantum field theory, with the aim to sense local properties of the field in a non-destructive manner. The field properties are sensed by weakly coupled pointers and encapsulated in conditional expectation values dependent on a postselection of the field state. Our operational protocol uses causally admissible Kraus updates for the field, in line with recent relativistic measurement theories, keeping in mind restrictions related to ``impossible measurements''. We illustrate our approach with three applications: a spacelikeness detector for causal-structure sensing, counting particle-creation densities in a supercritical potential and non-destructive discrimination between entangled states of the field and mixtures.

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F. Daem, L. Ballesteros Ferraz, A. Zampeli, A. Matzkin. 2026-07-20. Sensing relativistic quantum fields with minimally perturbing local measurements. https://arxiv.org/abs/2607.17920

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