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arXiv:2002.00832 · Physical Review Research

Weak values from path integrals

A. Matzkin

Published Aug 24, 2020• 5 citations
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Abstract

This work gives an account of weak values in terms of path integrals. The author shows how a weak value depends on the Feynman paths connecting the pre-selection to the post-selection regions that cross the area in which the weak interaction between the system observable and the pointer takes place
DOI
10.1103/physrevresearch.2.032048

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We connect the weak measurements framework to the path integral formulation of quantum mechanics. We show how Feynman propagators can in principle be experimentally inferred from weak value measurements. We also obtain expressions for weak values parsing unambiguously the quantum and the classical aspects of weak couplings between a system and a probe. These expressions are shown to be useful in quantum chaos related studies (an illustration involving quantum scars is given), and also in solving current weak-value related controversies (we discuss the existence of discontinuous trajectories in interferometers and the issue of anomalous weak values in the classical limit).
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