What type of multiverse is the DB Multiverse currently accepted as? Quilted?
If you mean the "canon" one, probably a variation of Tegmark Level 2 + Twin World Models of Universes + Brane (on a small level).
LEVEL 2: In the
eternal inflation theory, which is a variant of the
cosmic inflation theory, the multiverse or space as a whole is stretching and will continue doing so forever, but some regions of space stop stretching and form distinct bubbles (like gas pockets in a loaf of rising bread). Such bubbles are embryonic level I multiverses.
Different bubbles may experience different
spontaneous symmetry breaking, which results in different properties, such as different
physical constants.
Each Macrocosm is Level 2, as each Universe is made of multiple pocket spaces of different properties and physical laws. Of course, in Tegmark, those are Level 1 Multiverses, but here they're just universes. Then, as each Universe has a pair (and previously, a triplet), you get an explanation on why the Universes number in the 12 and have "mirrors," like 6 and 7.
TWIN WORLD MODEL: There are models of two related universes that e.g. attempt to explain the
baryon asymmetry – why there was more matter than
antimatter at the beginning –
with a mirror anti-universe. One two-universe cosmological model could explain the
Hubble constant (H0) tension via interactions between the two worlds. The "mirror world" would contain copies of all existing fundamental particles. Another twin/pair-world or "bi-world" cosmology is shown to theoretically be able to solve the
cosmological constant (Λ) problem, closely related to
dark energy: two interacting worlds with a large Λ each could result in a small shared effective Λ.
Which also explains why each Macrocosm has duplicates of the various properties and realms, like there being multiple Otherworlds. Obviously, the real answer is Rymus made them, but we're trying to fit within preset types, so presume that the spontaneous creation of a World from Rymus just acts the same for the sake of quantification. And finally...
BRANE: The
brane multiverse version postulates that our entire universe exists on a membrane (
brane) which floats in a higher dimension or "bulk". In this bulk, there are other membranes with their own universes. These universes can interact with one another, and when they collide, the violence and energy produced is more than enough to give rise to a
Big Bang. The branes float or drift near each other in the bulk, and every few trillion years, attracted by gravity or some other force we do not understand, collide and bang into each other. This repeated contact gives rise to multiple or "cyclic"
Big Bangs. This particular hypothesis falls under the string theory umbrella as it requires extra spatial dimensions.
Of course, this is far more advanced and isn't wholly applicable to Dragon Ball, but this is the closest analog to the Timelines, which hold duplicates of each set of Macrocosms in a
form of, vague, unexplained, bulk-space.
Then with Heroes, you just take this and apply an Infinite set of Timelines on it and other spaces that exist between or above/through them all (The Crack of Time, for instance), which would make it also part Many-World Interpretation. Or, in other words, a Level 3 Tegmark Multiverse.
LEVEL 3: Hugh Everett III's
many-worlds interpretation (MWI) is one of several mainstream
interpretations of quantum mechanics.
In brief, one aspect of quantum mechanics is that certain observations cannot be predicted absolutely. Instead, there is a range of possible observations, each with a different
probability. According to the MWI, each of these possible observations corresponds to a different "world" within the
Universal wavefunction, with each world as real as ours. Suppose a six-sided die is thrown and that the result of the throw corresponds to
observable quantum mechanics. All six possible ways the die can fall correspond to six different worlds. In the case of the Schrödinger's cat thought experiment,
both outcomes would be "real" in at least one "world."
That's the closest set of descriptions I could apply to the Multiverse of Dragon Ball. (Universe -> Small Multiverses in the Form of Macrocosm -> Larger Multiverse in the form of multiple Macrocosms -> Timelines as a larger Multiverse that all hold copies of the whole collection of Macrocosms).
