The idea of living in a parallel universe is equally fascinating and terrifying. Alternate realties, parallel dimensions and multi universes, whatever we call it, the notion of the other versions of existence is one of the most popular trends in science fiction, games and comics. From the franchises like ‘star trek’, ‘ doctor who’, ‘dragon ball’, ‘the chronicles of Narnia’ to science facts. The concept of parallel universe has invited us to think persons identical to us running around in some other dimension, reading this or living a complete different life from us, where the choices we have made had different results than the ones we know.
The mind startles at the concept of parallel universe which suggests that there could be the best version of you actually living in an other dimension!!
We actually have quite a bit of evidence for a parallel universe. But why do we think parallel universe exist in the first place?
Everything starts with the weird behaviour of quantum matter. At the quantum level, things behave differently from the classical one. For example, if we talk about the electrons: tiny, subatomic particles which can spin clockwise and counterclockwise at the same time.
We have never seen anything spinning in two directions at once. But the maths says that’s exactly what’s going on.
It’s like if we are saying that clockwise is ‘blue’ and counterclockwise is ‘yellow’ then electron can be “green”. And according to the quantum mechanics these green particles are everywhere, spinning in two directions at the same time.
But the question is if we are living in a world surrounded by these weird objects that are spinning clockwise and counterclockwise at the same time, why we have never seen that happen in our entire life?
The answer of this question is at the heart of ‘Quantum Measurement Paradox’, which will lead us straight to the parallel universe theory.
Quantum Measurement Paradox
The Heisenberg Uncertainty Principle suggests that just by observing quantum matter we affect the behaviour of that matter. According to Niels Bohr, this interpretation says that all the quantum particles don’t exist in one state or other, but in all of its possible state at once which is called its ‘superposition’. Observation of the particle breaks its superposition and essentially forces the object to choose only one state.
Here’s simple experiment for explaining this: We have an electron in a closed box and there are two conditions:-
- If the electron is spinning clockwise then a detector will be clicked and it will send a signal to a gun, which will then fire and kill a cat.
- And if the electron is spinning counterclockwise, then no further event will happen and the cat survives.
But, what if our electron is spinning in both directions at the same time? Here’s what this will look like:
So, is the cat alive or dead? Both.
# Zombie cat.
But we have never seen any kind of zombie cat.The answer is hidden in the Bohr’s interpretation.
Here’s what Bohr was suggesting:
In the 1950s, Hugh Everett ||| came up with an alternative way of explaining why we don’t see zombie cats at all around us.
He agreed with the idea of superposition but disagreed with Bohr in vital respect. To Everett, measuring a quantum object doesn’t force it into one comprehensible state or another. Instead, a measurement taken of a quantum object causes an actual split in the universe. The universe is literally duplicated, splitting into one universe for each possible outcome from the measurement.
So according to Everett’s explanation,
When the experimenter hasn’t looked inside the box, here’s how our system will look:
Now the experimenter looks inside and just like the cat, the gun, the detector, experimenter too split into two distinct copies of himself \herself:
And that was Everett’s point, where different versions of us see different–but well defined outcomes and his this ‘Many Worlds’ interpretation suggested that there are universes parallel to our own.
Like Many Worlds theory, ‘String theory’ demonstrates that parallel universes exist. According to string theory, the matter is created by the strings( that make up quarks: quantum particle) and the behaviour of matter depends on the vibrations of these strings. But unlike the Many Worlds theory string theory supposes that these universes can come into contact with one another.
So, are we actually living in a parallel universe? According to Many Worlds theory, we can’t truly be certain, since we cannot be aware of them.
The String theory has already been tested at least once– with negative result.
But if Many Worlds theory is correct, perhaps in that universe, we have already proved the String Theory or you have already pursued the thing you have been seeking.