[this is what I do when i get bored waiting for a train at a railway station]
The string theory was proposed in an attempt to unite all the laws of the universe to give ‘the theory of everything’. It simply states that the visible matter is nothing but the energy produced by the vibrations of ‘strings’, which are very much like that of a violin, or a guitar, but are very small (of the order of 10-33 cm or Planck length). If the atom were the size of the solar system, strings would be the size of an atom. Just as vibrations at different frequencies produce different notes in a guitar, vibrations of different strings give different matter.
Two main kinds of strings were theorized – open and looped. Both satisfied the mathematical equations. So far so good, but then the physicists encountered a problem. They came up with five different variations of the theory. This was a major problem – how can different theories explain the same universe? And if there are five, there can be more.
Then Edward Witten, the scientist/physicist from the institute of advanced science, came along and proposed that these theories are just images of a single theory (people believed him because he is said to have the highest IQ of all living humans). He went on to propose his own version of the theory called M-theory. According to this, the strings are not one dimensional, but three dimensional, and can be stretched like a membrane (simply called ‘branes’), few of them vast enough to cover the entire universe!
He also said that all the strings are open looped and are attached to this mega brane. But gravitons (the particles responsible for gravity) are closed looped and can roam around freely. They can also leave our universe and enter another and vice-versa.
If the above theory is true, then it may be able to explain the phenomenon of ‘Dark Matter’, which has puzzled the physicists for a while now. May be the extra gravitational force that the astronomers are detecting is not being exerted by some dark matter from our universe, but from the gravitons that escaped from a neighbouring universe and entered ours! In that case, there would be no need to look for dark matter, but other universes.
Scientists at CERN are conducting experiments to detect the gravitons that escape our universe in the particle accelerator. They crash two atoms at very high speed and detect new particles produced. If gravitons do have aforesaid property, then it will show it by its absence, i.e., experiments won’t be able to detect its presence.
Then three things will happen – it will be the first experimental proof of the M-theory; dark matter puzzle will be solved; and presence of multiverses will be confirmed. We live in interesting times indeed.