When does "Time" become "Observable" ?
  We investigate some spectral properties of time operators which are obtained through Canonical Commutation Relation (CCR) and Positive Operator Valued Measure (POVM) of quantum physics. In addition, we re-interpret the spectral properties of time operators from the standpoint of the Copenhagen Interpretation, especially, of W.Heisenberg. 
Tadashi Fujimoto (Department of philosophy, Ryukoku University Kyoto   Japan)
quant-ph