Protective measurement is a new measuring method introduced by Aharonov, Anandan and Vaidman (1993). By a protective measurement, one can measure the expectation value of an observable on a single quantum system, even if the system is initially not in an eigenstate of the measured observable. Aharonov, Anandan and Vaidman attributed this feature of protective measurements to a physical manifest...

The “potato kugel” theorem of Aharonov, Schiffer, and Zalcman, which concerns an inverse property harmonic functions, is extended to the settings modified Helmholtz equation that describe nuclear forces acoustic waves respectively.