Abstract
The question in the title may be answered by considering the outcome of a “weak measurement” in the sense of Aharonov, Albert, and Vaidman. Various properties of the resulting time are discussed, including its close relation to the Larmor times. It is a universal description of a broad class of measurement interactions, and its physical implications are unambiguous.
- Received 9 June 1994
DOI:https://doi.org/10.1103/PhysRevLett.74.2405
©1995 American Physical Society