The theory of everything - String theory (part one)
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The String Theory
The string theory has to be the most fascinating development in modern physics. The likes of which could make Newton shake his head in plain wonder. The sheer creativity that has led to the defining of this theory is amazing. It predicts multiple dimensions, parallel universes and other mind boggling concepts. Here I’ve summarized the string theory, right from the beginning in a simple way that it’s meant to be.
The universe comprises of four fundamental forces; strong force (nuclear force), weak force, gravitational force and the electromagnetic force. That being said, scientists (read: Einstein) dreamed of unifying these forces in a single elegant theory.
The beginning
In 1968, Gabriel Valenciano, an Italian physicist, stumbled upon a formula which seemed to explain the nature of one of these, the strong force. But soon after that, it stopped making sense and the study was abandoned. Then a physicist, Leonard Susskind, worked on that formula and after a lot of calculations (a little beyond our understanding) discovered that the formula described a structure. A structure shaped like a half cut string which could be stretched in any direction and also spiral across itself. Basically, it could have countless number of shapes, just like a string. Voila, a new particle called a string was predicted.
This discovery seemed to ignite a mass hysteria in the scientific community. Massive theoretical research took place in the field in the late sixties and early seventies, and after some initial success, major problems came up regarding the theory.
1) The theory predicted the existence of a massless particle faster than the speed of light, tachyon, which seemed impossible.
2) It predicted the existence of extra dimensions; next to the 4 we know (length, breadth height and time). Initially this seemed very cool but it did make the people of the science extremely uncomfortable.
3) It had anomalies. Like an equation that gives 2 values of an unknown (x) when u expect only one for it to make sense.
Failures after failures in dealing with these errors resulted in the string theory being discarded. Researchers quit, and the string theory became more of a philosophy than a science which had its momentary excitement to offer.
The Standard Model
During this time a new theoretical model gained significance, overshadowing the string theory. The Standard model. It unified 3 of the 4 forces in nature stating that each force had a fundamental particle, called a messenger particle. A force was “felt” between two objects when the messenger particles oscillated between them. The higher the speed of these particles, the stronger the force felt. These particles were indeed discovered and photon was the messenger particle of the electromagnetic force. This theory somehow failed to account for gravity and its messenger particle, the very hypothetical, graviton. The strong force, weak force and the electromagnetic force were united beautifully but gravity was left out. Science was at a dead end.
To rescue the day, two men John Henry Shwarz and Michael Green, amongst the last string theory researchers had a brain storm and came up with the most amazing hypothesis that solved all the problems of the string theory and eventually resulted in a satisfying explanation leading to the prediction of multiple dimensions and parallel universes!
