From what I understand of the 'theory', quantum fluctuations are not 'causal' events that occur in time. It is only by linking together a particular sequence of these fluctuations that you end up with a time-like ordering and a process happening in time.
Quantum fluctuations are absolutely the weirdest phenomena in quantum theory because although we like to imagine them like waves and ripples that come and go on some surface like water, the mathematics say that they are statistical, random and a-causal variations in some quantity of interest ( energy, mass, spin, charge, curvature) that have nothing to do with time ordering.
We can no more intuitively understand what these are, than we can understand what quantum' spin' is, or how it is possible for the speed of light to be constant no matter how fast you are moving. No matter what kind of mental model we try to use to describe a 'fluctuation' we always seem to think in terms of something changing in time. But general relativity says that there was no time 'before' the big bang. That is why general relativity and quantum mechanics have a hard time speaking to each other.
Copyright 1997 Dr. Sten Odenwald
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