The equivalence statements for quantum scalar field vacuum states that have
been used for the thermal-like Hawking effect and Unruh effect are surveye
d. An important ingredient in this framework is the concept of a vacuum Fie
ld noise spectrum, by which one can obtain information about the curvature
invariants of classical worldlines (relativistic classical trajectories). I
t is argued, in the spirit of the free-fall-type universality that the pref
erred quantum field vacua with respect to accelerated worldlines should be
chosen from the class of all those possessing stationary spectra for their
quantum fluctuations. For scalar quantum field vacua there are six stationa
ry cases, as shown by Letaw some time ago, and reviewed here. However. nons
tationary vacuum noises can be treated by a few mathematical methods that a
re mentioned as well. Since the information about the kinematical curvature
invariants of the worldlines is of radiometric origin, suggestions are giv
en on the more useful application of such an academic formalism to radiatio
n and beam radiometric standards for high-energy accelerators and in astrop
hysics. We conclude with a look at related axiomatic quantum field topics a
nd some other recent work.