Traditionally, in non-relativistic Quantum Mechanics, time is considered to be a parameter, rather than an observable quantity like space. In relativistic Quantum Field Theory, space and time are treated equally by reducing space to also be a parameter. Herein, after a brief review of other measurements, we describe a third possibility, which is to treat time as a directly observable quantity.
Document ID: 19950007504. Accession ID: 95N13917. NASA. Goddard Space Flight Center, Third International Workshop on Squeezed States and Uncertainty Relations; p 167-172.