The discussion centers on the nature of quantum fluctuations in the vacuum as predicted by relativistic quantum field theory (QFT), particularly in relation to the Casimir Effect. Participants explore the terminology and implications of vacuum energy and fluctuations, as well as the physical interpretations of the Casimir Effect.
Participants express differing views on the interpretation of vacuum fluctuations and the Casimir Effect, indicating that multiple competing perspectives remain without consensus.
There are unresolved questions regarding the definitions of vacuum energy and fluctuations, as well as the implications of energy differences in the context of quantum field theory. The discussion also highlights the complexity of the Casimir Effect and its interpretations.
We do not. The Casimir effect can be explained purely as electromagnetic force between the electric charges in the plates: The Casimir Effect and the Quantum VacuumJrs580 said:We see this in the experiment proving the Casimir Effect so we know it's physical
In SR there is no physics in the absolute value of the total energy, and thus it's convenient to associate the values 0 of the Poincare-invariant vacuum state for all additive conservation laws. Formally you can achieve this with introducing "normal ordering" in the Hamiltonian/Lagrangian.malawi_glenn said:Vacuum fluctuation is not a good term, vacuum energy is better (zero point energy). Vaccum here means absence of particles.
The Casimir effect is due to fluctuations of charges and the em. field. The usual calculation you find in introductory chapters of some QFT books (e.g., in Itzykson, Zuber) is a limiting case for infinite (!) charges. For details seemalawi_glenn said:Hard to understand your "why" question, do you want to see the casimir effect calculation or what else are you referring to?