  I suggest that measurement in quantum theory should be regarded as a sense of
time (of things happening), which is as important as the conventional
relativistic notion of time. A key question -- of basic physical interest
whether one accepts the arguments here or not -- is, What physical criteria
determine when a measurement takes place? I suggest a way in which the answer
to this may be bound up with the resolution of some pathologies associated with
the stress-energy operator, and may at the same time determine the cosmic flow
of time. The problem of reconciling the quantum sense of time (measurement) and
the conventional relativistic one gives some indication that the the correct
"quantization" of gravity is essentially different from that of other fields.
