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If you look at the staggered troughs of the true/false vacuum and compare this with the Higgs potential, then the Higgs mechanism would have to favour a false vacuum in order to supply a mass term.
…Quantum mechanics provides us with this type of vacuum, because it forbids us from having a classical vacuum, which can be identified as absolutely nothing.
…If the vacuum is a reality, and there is good reason to think it is, there has to be the possibility that the vacuum is “something”. In fact, to the best of our knowledge, the vacuum is, on the scale of the Planck’s length, a very active and energetic place.An additional requirement (one that for reasons which I find inexplicable, some experts hesitate to agree with) is that either this vacuum must be eternal, or it must have emerged from something else.
You could explain virtual particles in terms of quantum oscillations between the true and false vacuum states. This cannot be thought of in terms of tunneling, since this does not involve real particles. This speculation likely falls down for various reasons. I don't know enough to judge. Maybe others can comment.
Virtual particles conserve energy and momentum while they are present
Thoughts about an energetic vacuum. Absence makes the thoughts grow weirder!I keep finding my thoughts back at the OP, and wondering if I can find time to pick through this thread to see if the answers to my inevitable questions are in there somewhere. If they are, please forgive me, but I’m going to ask for some responses to these thoughts. It makes no sense to talk of an absolute vacuum filling space. An absolute vacuum is nothing, so it can fill nothing. As soon as one starts to think of a vacuum as having qualities, the concept changes, the vacuum becomes something, and has to be somewhere. If the “vacuum of space” has energy, it is something; so, where is it? Instinctively, the answer would seem to be “everywhere”; it fills the Universe.Would it be more meaningful to say that it is the Universe? This would mean that what we perceive as matter and energy are physical manifestations of the all-pervading vacuum energy.Further consideration of the idea that the vacuum energy fills the Universe must lead one to ask if, in fact, it goes beyond that. If we accept that the Universe came into being at the Big Bang; and if we accept inflationary theory, which I am doing for the purposes of this line of thought, then our Universe began as a “quon-sized” scalar field, “rolling about” on a hypothetical landscape that represents the vacuum energy. It would follow from this that the energetic vacuum must have preceded the existence of the Universe.Can we say anything about the possible extent of the vacuum, in this case?Must it be infinite?Must it always have existed?Is there any alternative to either of those?
In the theoretical physics of the false vacuum, the system moves to a lower energy state – either the true vacuum, or another, lower energy vacuum – through a process known as bubble nucleation.
If two bubbles are nucleated and they eventually collide, it is thought that particle production would occur where the walls collide.
Trying to make a start on #45.Quote from: Bogie_Smiles Virtual particles conserve energy and momentum while they are present So Wiki assures us, but here we are talking cosmic scale. Is energy necessarily conserved in an expanding universe?
I know of no particle interactions or energy events where energy is not conserved.
Quote from: Bogie_SmilesI know of no particle interactions or energy events where energy is not conserved. Nor do I; but if you are linking virtual particle interactions to expansion of the Universe (italics added), then it might be appropriate to remember that energy is not necessarily conserved.
The thing missing in the conversation is zero point energy. How does this relate to the idea of a false vacuum? This is considered to be a ground state. Is this a false ground state?
…The comment should be confined to the presence of virtual particles, when they pop into and out of existence, presumable from the energy of the local vacuum….
There is a tendency to equate the use of the phrase “expansion of the Universe” to the implication that the whole universe is expanding, when actually only a portion of the space that is referred to as “causally connected to our big bang event” is visible in our Hubble view.
Is it just me, or is there an inclination to equate such bubbles in QFT to some version of the initial events related to Big Bang Theory with Inflation?
Quote from: Bogie_Smiles …The comment should be confined to the presence of virtual particles, when they pop into and out of existence, presumable from the energy of the local vacuum….This is my simplistic understanding:1. Energy is borrowed from the vacuum energy to bring a perturbation into existence. This is identified as a virtual particle.2. Repayment of the energy is to the vacuum. Some authors say it must be replaced “before the vacuum misses it”. I would question this.3. The vacuum is an integral feature of the Universe. 4. If it were possible to observe the energy while it was being borrowed, it might not be where classical physics says it should be, if classical physics could be applied, here. However, it must still be in the Universe.5. At no time does energy leave or enter the universe; therefore, conservation of energy is not violated. Any violation of energy conservation in an expanding universe does not arise from virtual particle creation/annihilation. (Sticking my neck out!)QuoteThere is a tendency to equate the use of the phrase “expansion of the Universe” to the implication that the whole universe is expanding, when actually only a portion of the space that is referred to as “causally connected to our big bang event” is visible in our Hubble view. As far as I am aware, we have no direct evidence of anything that is not “causally connected to our big bang event”. It would seem reasonable to suggest that anything “beyond” is either expanding with the observed Universe; or is not in direct/active contact with it.Quote Is it just me, or is there an inclination to equate such bubbles in QFT to some version of the initial events related to Big Bang Theory with Inflation? It’s not just you!Quote from: Bill S on 06/08/2018 18:32:49Here's one I thought earlier.Ref. #10: If/when a scalar field settles in a “valley”, what determines whether it remains or discharges its energy?
Here's one I thought earlier.Ref. #10: If/when a scalar field settles in a “valley”, what determines whether it remains or discharges its energy?
"In quantum field theory, a false vacuum is a hypothetical vacuum that is somewhat, but not entirely, stable." I don't believe anything to be entirely stable, so is it just a time frame thing? https://en.wikipedia.org/wiki/False_vacuum
Standard Model Vacuum from Wiki:If the Standard Model is correct, the particles and forces we observe in our universe exist as they do because of underlying quantum fields. Quantum fields can have states of differing stability, including 'stable', 'unstable', or 'metastable' (meaning very long-lived but not completely stable). If a more stable vacuum state were able to arise, then existing particles and forces would no longer arise as they do in the universe's present state. Different particles or forces would arise from (and be shaped by) whatever new quantum states arose. The world we know depends upon these particles and forces, so if this happened, everything around us, from subatomic particles to galaxies, and all fundamental forces, would be reconstituted into new fundamental particles and forces and structures. The universe would lose all of its present structures and become inhabited by new ones (depending upon the exact states involved) based upon the same quantum fields.