One of the most important theories of cosmology and modern quantum physics points out that it is quite possible that our universe is only one more among a bunch of universes - possibly infinite.
This same theory, known as multiverse, honoring its name is divided into multiple theories, all of which address this possibility with a theoretical-mathematical support.
Although the term "multiverse" was coined by the famous psychologist William James (brother of the novelist Henry), perhaps the first serious consideration within physics was that made by Hugh Everett in 1957, with his theory of the many worlds.
This theory, which explains quantum mechanics, broadly suggests that certain observations cannot be predicted at all; instead, there is a wide range of possible observations with a different probability: each of the possible observations corresponds to another universe.
This is the seminal theory of the multiverse or parallel universes, when we observe, measure or decide, we branch into another universe where our double dwells and so on to infinity. Let's see how this theory has evolved among cutting-edge physics, according to the Space.com site.
1- Infinite Universes
Scientists do not know well what form the universe has - according to some theories it is spherical or has a toroidal shape - but the most popular version of the geometry of the cosmos maintains that the universe is flat and extends infinitely. This leaves us with the paradox that if spacetime has an eternal duration, then it must be repeated at some point, since there is a finite number of ways in which particles can be combined in space.
If we could travel the universe far enough, you would find a version of yourself - in reality, if you traveled space time infinitely you would find yourself infinite. Some of these doubles would hardly vary by a microdetail (like having a glass of water before going outside); others could vary almost infinitely.
2- Bubble Universes
In addition to the multiple universes created by infinite extension of time-space, other universes could arise from what is known as "eternal inflation." According to the theory of inflation, in the beginning the universe expanded very quickly, in an effect similar to that of a globe. Eternal inflation suggests that some bags of space stopped inflating while others continued to do so, giving birth to "isolated bubble universes."
3- Parallel Universes
These bubble universes could be very strange places, with other physical laws, compared to our universe where inflation has ended.
Linked to the theory of superstrings, the worlds-branes could compose parallel universes just outside the scope of ours in extra dimensions to the daily three-dimensional space. Brana universes could float within our same space-time in higher dimensions, as physicists Paul Steinhard and Neil Turok have theorized.
According to Brian Greene of Columbia University, the notion that our universe is one among potentially infinite, can be imagined as if we were just a slice of a multidimensional cosmic bread.
4- Sons Universes
Quantum physics describes a microscopic world in terms of probabilities rather than definitive results. The mathematics that support it suggests that it is possible for all possible outcomes within a situation to occur - in their own separate universes.
For example, when someone faces a crossroads, two universes are generated, one in which he takes the right path and the other the left. "And in each universe there is a copy of yourself witnessing one of the results - thinking that your reality is the only reality, " says Greene.
5- Mathematical Universes
Scientists have debated whether mathematics is simply a useful tool for describing the universe, or is actually a fundamental reality - our perception would be just an imperfection of the true mathematical nature of the universe. If such is the case, then perhaps the particular mathematical structure that composes the universe could be only one among several other separate mathematical structures.
Here is a video of Nat Geo explaining the Theory of the Multiverse:
[youtube] http://youtu.be/xn6h6qhntpc [/ youtube]
Source: http: //ciudadesplanetarios.com/5-razones-que-explican-la-teoria-del-multiverso/
