First of all, would I be correct in using the following explanation? Quantum fluctuations are not actually events but properties of the quantum vacuum, they don't have a physical cause but they are not an example of creation ex nihilo, they are created from other things. I think of it like a shaking of a soda can. The quantum vacuum is the soda and the fluctuations are the bubbles that appear when you shake the can. In case I have not been clear let me line up my questions: 1) Are quantum fluctuations an example of creation out of nothing (not anything) ? I am correct in saying that there is no such a thing in physics? 2) Do quantum fluctuations have a physical cause? 3) What exactly makes the quantum vacuum fluctuate? 4) What are quantum fluctuations "made of" ?