Observing physical effects of large quantum stress tensor fluctuations
requires knowledge of the interaction between the probe and the particles of
the underlying quantum fields. The quantum stress tensor operators must first
be averaged in time alone or space and time to confer meaningful results, the
details of which may correspond to the physical measurement process. We build
on prior results to characterize the particle frequencies associated with
quantum fluctuations of different magnitudes. For the square of time
derivatives of the massless scalar field in a spherical cavity, we find that
these frequencies are bounded above in a power law behavior. Our findings
provide a way identify the largest quantum fluctuation that may be probed in
experiments relying on frequency-dependent interactions.Comment: 23 pages, 4 figures, 1 tabl