Multiverse Alternate Timelines and Copies of You and Me

There are scenarios in Quantum mechanics, Theory of eternal inflation, and String Theory that allows for the possibility of existence of Multiverse that is countless other Universes apart from our own. In this Multiple Universe picture there may exist another Universe very similar to our own as the math of the theory suggests. None of the observations made so far have contradicted Quantum mechanics, it has proven to be correct over and over again, and if the same theory allows for a Multiverse, then there is a strong chance. Data from NASA’s WMAP and latter ESA’s Planck Satellite supports the predictions of inflation theory which makes a good case for the possibility of multiple Universes as in the theory of eternal inflation. String theory has elegance and it holds together beautifully and experiments are being conducted in particle accelerators all around the world to test its predictions. There is a strong chance that results will be affirmative.

Many world interpretation/Everett interpretation of quantum mechanics simply suggests that all the possible outcomes of a quantum event do really gets played out, only in other Universes that are non communicative and increasingly divergent. All the probable outcomes do really occur, they just occur in other Universes. It asserts that universal wave function gives us a good picture of reality; we just need to find a way to verify it. Many world interpretation talks about Quantum decoherence. For every possible outcome of a quantum event an alternate time line exists which is divergent to other time lines. This is what the math of the theory indicates. Tests are being devised to verify the predictions of this interpretation. There are both proponents and opponents of this theory.

Theory of eternal inflation draws from the theory of inflation and says that inflation caused by false vacuum energy never stops. False vacuum energy decays here and there creating regions with lesser rate of inflation. These comparatively lower inflation rate regions are local universes. Inflation continues to happen at higher rate outside of this region and continues to decay every now and then giving rise to countless such universes. Scientists are hard at work trying to figure out ways of testing this theory. If two such universes were close enough at their formation then they might have collided leaving an energy signature. Colliding universe scenario has been simulated and people are looking hard at data obtained from high sensitivity Planck satellite to find those signs in cosmic microwave background radiation. With even better satellites and probes we will have an even better chance of detecting these signs.

Yet another theory that gives us a possibility of multiple Universes is the string theory. It points that, tiny strings of energy vibrating or wiggling in different patterns along 3 dimensions of space, one of time and 7 other dimensions, form different subatomic particles. These strings can be open ended with each end tied to a plane of existence or they can be like closed loops. Open ended strings are tied to their plane and therefore cannot move freely to other planes of existence. However, close ended strings are not attached to their plane and therefore can move to other planes of existence. From this theory comes the idea of Branes. Theory hints of parallel planes or Branes spreading across higher dimensions. These parallel Branes collide from time to time causing energy conversion creating local universes one of which is ours.

Dimension is akin to degree of freedom of movement. We only have freedom to move along 3 spatial dimensions which we denote as dimensions X, Y, Z and one temporal dimension. String theory requires the existence of seven extra dimensions. This is what math of theory calls for in order to make sense. If those extra dimensions do really exist, then why we have not been able to sense their existence? If graviton is detected by particle accelerators, it may signal the existence of these extra dimensions as one of the properties of graviton is its ability to move along dimensions other than the ones associated to its Brane. As the graviton disappears into one of those higher dimensions, we will know.

One way to test #StringTheory is to find Sparticles, whose existence is supported by it. It is called Supersymmetry and it suggests that there is a Sparticle for every particle in standard model. Standard model is incapable of answering all questions such as why Higgs Boson is light, on its own, giving rise to the requirement of Sparticles. Sparticles or superpartners are much heavier than their symmetrical pair and their inclusion gives better solution to our questions and enriches Quantum mechanics even more. Hunt is on at every major particle accelerator around the world to detect one.

Weakness of gravity as compared to other fundamental forces of nature is explained by string theory. It argues that gravity may be caused by a closed string of energy- a graviton or gravity particle and since closed strings are not tied to their Branes they are free to move to other Branes, which reduces their concentration and thus intensity. People are at work in particle accelerators such as the LHC at CERN to detect a graviton, which will also give support to the idea of extra dimensions whose existence is required for String theory to make sense.

Three theories suggest the possibility of a #Multiverse, I would say, chances are pretty strong that we live in a Multiverse and probably there are people out there very similar to ourselves in alternate timelines in other Universes. Many world interpretation also allows for the possibility of communication between two Universes that corresponds to two possible outcomes of an event, making a way for testing this theory. Another way of communication could be gravitons as they can move freely between parallel Branes. With more powerful and more sensitive equipments coming up in future, who knows what we may find.

References:
1) https://plato.stanford.edu/entries/qm-manyworlds/

2) https://arxiv.org/pdf/hep-th/0702178.pdf

3) https://arxiv.org/pdf/1512.02477.pdf

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