Weak measurements measure probability amplitudes (and very little else)

Abstract

Conventional quantum mechanics describes a pre- and post-selected system in terms of virtual (Feynman) paths via which the final state can be reached. In the absence of probabilities, a weak measurement (WM) determines the probability amplitudes for the paths involved. The weak values (VW) can be identified with these amplitudes, or their linear combinations. This allows us to explain the "unusual" properties of the VW, and avoid the "paradoxes" often associated with the WM.

References in corpus (4)

• How the result of a single coin toss can turn out to be 100 heads
• The meaning of "anomalous weak values" in quantum and classical theories
• Path integrals, the ABL rule and the three-box paradox
• Feynman-path analysis of Hardy's paradox: measurements and the uncertainty principle

Cited by in corpus (21)

• Null weak values and the past of a quantum particle
• Weak values and quantum properties
• The Quantum Cheshire Cat effect: Theoretical basis and observational implications
• Observing the "quantum Cheshire cat" effect with noninvasive weak measurement
• Probing finite coarse-grained virtual Feynman histories with sequential weak values
• Direct evaluation of measurement uncertainties by feedback compensation of decoherence
• Comment on the MS "Null weak values and the past of quantum particle" by Q.Duprey and A.Matzkin
• Contextuality, Coherences, and Quantum Cheshire Cats
• Path probabilities for consecutive measurements, and certain "quantum paradoxes"
• The Salecker-Wigner-Peres clock, Feynman paths, and a tunnelling time that should not exist
• Reply to Comment on "Null weak values and the past of a quantum particle" by D. Sokolovski
• Do weak values capture the complete truth about the past of a quantum particle?
• Speed-up and slow-down of a quantum particle
• Dependence of measurement outcomes on the dynamics of quantum coherent interactions between the system and the meter
• Uncertainty limits of the information exchange between a quantum system and an external meter
• Restrictions on the existence of weak values in quantum mechanics: weak quantum evolution concept
• Speakable and unspeakable in quantum measurements
• Stories in the two-state vector formalism
• Continuous fuzzy measurement on two-level systems revisited
• Unitary evolution and elements of reality in consecutive quantum measurements
• Time Derivatives of Weak Values