One of the signature ideas behind the concept of the multiverse, as it exists today, is the idea that different universes would have different laws. The coincident multiverse proposes a potentially infinite number of different universes that have the same laws; which is, I believe, a departure from what we might call the current "standard model" of the multiverse.
I propose this simply because law is law; in biology, we know that convergent evolution produces the same morphological types over and over again, simply because that is what works. In the same way, chemistry produces similar substances to perform specific functions in biological organisms, which are often surprisingly similar – or even nearly identical — in a wide range of different creatures, simply because chemistry has laws, and what works in one case is what will work in another.
The idea of the coincident multiverse is a somewhat more powerful one, because it argues that the particles we have in this universe — which "appear" and "disappear" in a baffling and seemingly impossible manner — are the same in all the universes, and that they serve the same function in all those universes. They are an ethereal fabric upon which all of the universes that arise as a result of them are based. The idea of the coincident multiverse is, in other words, a consonant multiverse, one in which an essentially identical quantum fabric is shared across a range of individual space-times. When one thinks about it, the proposition is in fact quite logical.
Much has been made in modern physics of the fact that if the physical laws of this universe were even a tiny bit different, the universe could not exist. I have yet to read a physicist who has asked the question, what if the laws cannot be different? That is to say, what if the idea of the consonant/coincident multiverse is correct, and that universes can only exist one way, that is, by the exact and singular manifestation of the laws we perceive? This is reminiscent of Gurdjieff's statement that for one thing to be different, everything would have to be different. Physics imagines multiple universes where the alteration of law puts them beyond the reach of each other; but in putting them in such a region, we also put them beyond the reach of reality as we know it.
I think this is the essential problem with claiming that quantum particles appear and disappear — nothing that we know of appears and disappears by some invoked magic that allows it to exist in this universe, cease existing, and then exist again on a scale of time so tiny that it is nearly immeasurable. The quantum particles — the energy packets that appear and disappear — do not cease to exist in these instants — they simply relocate from one position in one universe to a consonant position in another nearly identical universe, which shares identity through law, although not necessarily the exact progression of circumstance. That is, although their specific role will vary from universe to universe, their power, their action, the mechanistic nature of their manifestation, does not vary. A gluon in this universe does the same thing that it does in all the other universes it transits in a single second.
This proposition preserves the information in atoms and subatomic particles, as well as the logic behind their existence — the alternate universes they arise in also benefit from their information package, just as ours does. The mechanism does not require quantum particles to perform magical feats of death and reincarnation — it logically explains their departure and arrival from measurable existence through a mechanism of location alone.
Our consciousness and awareness of ourselves may perform quite similar functions, and pondering this could be of considerable interest. It may be that consciousness and awareness which we experience is shared on levels that we are unaware of, which bear a direct relationship to the consonant or coincident universe theory.
Human beings have a habit of inventing fantasies that lie beyond any possible reality; yet any scientist would tell you that, generally speaking, reality as we see it makes a good predictor for what will come next. This proves true over long stretches of historical time in biology, physics, chemistry, and even in societies and philosophies. There is, in other words, a consistency that only fantasy (in the sense of imagining what could only be unreal) can transcend. Swedenborg, among others, insisted that the entire natural world as we see it is a correspondence to a higher spiritual level; that is, his own model of earth and heaven rested on the idea that the identity was significantly shared. To the point, he said earth and heaven are so alike that many souls who die are not aware they are dead unless it is clearly explained to them.
The metaphysical implications of these ideas are too large for me to digest in a few brief days; I suspect I'll be pondering them for some time.