Multiverses are successor verses to universes. Definitions of a multiverse vary, but it is generally agreed upon that a multiverse is a collection of many universes (or rarely one universe), whenever they are contained physically, within a timeline, within a higher level of reality, etc.
A multiverse to a human would seem very huge; it is a space of many universes. However, this doesn't stop multiverses from being contained within "superior" verses.
As multiverses have to be contained due to not having any "endless" properties, multiverses are contained within Metaverses if a multiverse is considered to be a superior level of reality to a universe, and within Megaverses under most other definitions.
"Our multiverse" is the multiverse that our universe is local to and that is local to to the universe's 3 dimensional ambient space. This definition implies that the universe in our multiverse share common laws, yet were formed by different points in the Multigraph that our Multiverse formed from.
Our universe also has approximately 10^10^10^120 universes, although a multiverse under similar conditions to ours can contain anywhere from only 2 universes to a billion universes.
Our universe lasts long, but most of them only live for xonoseconds and pop due to the way the way universes form.
The diameter of the Local Multiverse is on the order of 92,200,000,000 * 10^10^10^120 light years across!
Alternate Types of Multiverses
It is an infinte universe collection. The universes in this type of multiverse should be refreshing itself and should have a starting and extention. It results with infinite amount universe that all has the same physical laws but different starting and extention. So matter configurations are also different. Universal distance should be 10^10^115 lightyears.
Universes should be multi-dimensional (at least 1D) and should be refreshing itself and streching forever. These type of multiverses may contain Mini-Multiverse. Physical laws of universes should be different.
Quantum Multiverse (other worlds theory)
In a quantum multiverse, each possible state of the universe is a different basis vector in a Hilbert space, and the overall state of the universe is a vector in this Hilbert space; this state is called the universal wavefunction. =
Systems that are separated out from their environment can be factored out of this vector, and when they interact with the environment ("are measured"), each possible state of the system leads to a different world.
For example, suppose there is an isolated two-state system with equally likely states
, and the rest of the universe with the state
such that the universal wavefunction can approximately be written as
- if this system interacts with the rest of the world, then it may no longer be possible to factor out, and the universal wavefunction becomes
, now containing two different worlds.
In a mathematical multiverse, all mathematical structures are real, and each mathematical structure corresponds to a different universe.
VoidSansXD's Proposed Type
VoidSansXD proposes that all types of Parallel Universes with the same universal properties (AKA laws) are all put into one set of parallel universes, and other sets of parallel universes contain Universes with different universal properties/laws. For example, all universes where the 4 fundamental forces and all subsets of it are the same as ours would be 1 set, and another set could have a different size for the Planck Length. They could also have different probabilities for things to happen, meaning that quantum physics/entanglement being different in different universes/objects could also put universes into different sets. Basically, this proposal is a mix of the mathematical multiverse and the extention multiverse.
A civilization that controls all of the resources available in an entire Multiverse is called a Type 5.0 Civilization.