European Journal of Physics
The Wigner function. I. The physical interpretation
Stig Stenholm
Abstract
It is being argued that even in non-relativistic quantum mechanics the coordinate and momentum variables cannot be interpreted directly as observables. Only by defining these by suitable test bodies can one obtain verifiable predictions. When these arguments are implemented on a Wigner distribution the author shows that positive phase space probabilities always ensue, and hence this function can be used as a quantum mechanical phase space function.