Have you ever wondered what would have happened if you went right instead of left? Or what if you were never even born? Our world may not be the only world; the Multiverse Theory states that there are infinite numbers of parallel worlds with different realities. If you are a Marvel fan, multiverse theory was discussed in movies such as Doctor Strange and Spider-Man: Far From Home and even in Spider-Man: Into the Multiverse. To help you better understand this theory, here are some facts that will give you an insight:
It was first coined by physicist Hugh Everett in 1957.
Hugh Everett’s many-worlds interpretation arose from what must have been the most ingenious drinking discussion, probably in all the time. One evening in 1954, inside the student hall at Princeton University, grad student Everett was drinking with his friends when he came up with the idea that quantum effects cause the universe to constantly split
He developed this idea for his Ph.D. thesis–and the theory held up. According to his work, we are living in a multiverse of countless universes, full of copies of each of us. It was scandalous.
Different realities may have a different set of rules for science
In our reality, we have a set of rules for physics and mathematics, and other sciences, but there is a possibility that there might be different rules or functions in other realities. To best explain this, we take the example of famous Schrödinger’s cat paradox which puts a cat in a box with a substance that can kill it, now the box is closed, the cat can either be dead or alive. Now apply this to the multiverse theory. Whenever you open the box, reality splits into two versions. In one reality, you could stare at a dead cat whereas, in the other reality, the cat would be perfectly fine.
The Multiverse Theory allows there to be an infinite number of worlds
We are still not sure how big the universe is, it could be never-ending or it could be finite, but when we leave Earth, we all imagine it to stretch for billions of light-years. This leads to the question that if the universe is infinite, there could be infinite multiverse. Imagine you have 10 different colored sticks, no matter how many times you arrange it, at one point you will repeat the order. Similarly, in an infinite universe, the realities eventually would have to repeat itself and arrange itself in similar patterns. A multiverse, with an endless number of parallel realms containing similar but slightly different versions of everything.
It can help understand how the universe began and how it might end
Human beings have a psychological desire for completion of things, we need to know how things came to be and how it will end. We are all told how The Big Bang was the birth of our universe but how did it come to be? What existed before it ever happened? What triggered it? Such questions can be answered by the multiverse theory. Some physicists have hypothesized that the infinite regions of the multiverse are called braneworlds. These braneworlds exist in many different dimensions, but we can’t detect them, because we can only perceive the three dimensions of space, plus the fourth dimension of time, in our own braneworld. It is also hypothesized that occasionally; the braneworlds bump into each other. Hypothetically, those collisions can cause repeated, Big Bang.
Time Travel Paradox
In movies such as Back to the Future, we can see that the things changed in the past can change the future but if the multiverse theory is applied, it might be possible that instead of a different future in our timeline, a parallel world is created with a different timeline caused by the change made in the past. Sadly, we cannot confirm this as we still have not created time travel, but no doubt we would like to change some things in our past.
People have thought of the possibility of different worlds since the dawn of man.
This isn’t hard proof. But it’s important to remember the old saying that if you can imagine something, it must exist. In Medieval times, multiple universes were also a prospect. In 1277, for example, the Bishop of Paris even argued that Greek philosopher Aristotle had been wrong to say there was only one world because this questioned God’s power to create parallel worlds. The idea was resurrected once again in the 1600s by Gottfried Wilhelm Leibniz, one of the leaders of the Scientific Revolution, who argued that there were many possible worlds, each with different laws of physics.
Heisenberg Uncertainty Principle
Physicists studying the quantum level noticed some peculiar things about this world. For one, the particles that exist on this level have a way of taking different forms. For example, scientists have observed photons which are tiny packets of light, acting like particles and waves. Even a single photon exhibits shape-shifting. This is known as the Heisenberg Uncertainty Principle. Thus, we can never be fully certain of the nature of a quantum object or its attributes, like velocity and location.
Quantum Suicide
So how could we ever know if the Many-Worlds theory is correct? Assurance that the interpretation is theoretically came in the late 1990s from a thought experiment; an experiment used to theoretically prove or disprove an idea called quantum suicide. This thought experiment renewed interest in Everett’s theory, which was for many years considered rubbish. Since Many-Worlds were proven possible, physicists and mathematicians have aimed to investigate the implications of the theory in depth.
String theory in relation to the Multiverse Theory
Like the Many-Worlds theory, string theory shows that parallel universes exist. According to the theory, our own universe is like a bubble that exists alongside similar parallel universes. Unlike the Many-Worlds theory, string theory supposes that these universes can come into contact with one another. String theory says that gravity can flow between these parallel universes. When these universes interact, a Big Bang like the one that created our universe occurs.
Arguments against the Multiverse Theory
The multiverse idea is provable neither by observation nor as an implication of well-established physics. It may be true, but it cannot be shown to be true. It has great explanatory power, but one must distinguish between explanation and prediction. Many physicists have gone against this theory as it has no hard evidence, and different dimensions cannot be perceived by the human brain.