I was wondering about whether quantum fluctuations can really violate energy conservation. For example, as far as I know, virtual particles are a result of the Heisenberg uncertainty principle, and according to this site,
"Quantum mechanics allows, and indeed requires, temporary violations of conservation of energy".
Now, I know the virtual particles are there for a very (insanely) short time period before mutually annihilating, but energy conservation was still violated, right?
On the other hand, I've seen this post, this post, this post, and this post, and searched online, and I read that virtual particles are mainly derived from the mathematical aspect of physics and Feynman Diagrams. So many people say they don't "exist", so to speak.
I know many scientists are still speculating, debating, and investigating whether virtual particles really exist or not, but if they did, would they be an exception to the law of conservation of energy? Thanks.