Angle states in quantum mechanics

Angle states and angle operators are defined for a system with arbitrary an gular momentum. They provide a reasonable formalization of the concept of a ngle provided that we accept that the angular orientation is quantized. The angle operator is the generator of boosts in angular momentum and is, almo st everywhere, linearly related to the logarithm of the shift operator. Ang le states for fermions and bosons behave differently under parity transform ation. (C) 1998 American Association of Physics Teachers.