MINIMUM-UNCERTAINTY ANGULAR WAVE-PACKETS AND QUANTIZED MEAN-VALUES

Uncertainty relations between a bounded coordinate operator and a conj ugate momentum operator frequently appear in quantum mechanics. We pro ve that physically reasonable minimum-uncertainty solutions to such re lations have quantized expectation values of the conjugate momentum. T his implies, for example, that the mean angular momentum is quantized for any minimum-uncertainty state obtained from any uncertainty relati on involving the angular-momentum operator and a conjugate coordinate. Experiments specifically seeking to create minimum-uncertainty states localized in angular coordinates therefore must produce packets with integer angular momentum.