Gauge Newsletter January 2019 | Page 42

The Story of the Theory of everything ............................................................................................ The good old quantum field theory! What is the true nature of the universe? To answer this question people came up with different stories since the beginning of mankind. First, they looked at the surrounding with the naked eye and they built stories around them. But when they came across situations that they cannot explain with those stories, they had to change the stories. Later on, with the advancements of vision technologies, they started to observe minute particles closely. They concluded that the matter is made up of ‘atoms’ and that the atom is the smallest layer of reality. But as time passed, they were able to smash atoms together and discovered elementary particles. Since they are so small, they couldn't see them even with the most advanced lenses. The light we use to see things is an electromagnetic wave. Since elementary particles are very small, this electromagnetic wave misses the particles. To overcome this problem, they tried making the wavelength shorter. By doing so, they increased the energy of the wave. As a result, when they tried to observe the particles, they were already changed by the sheer impact of that energy. So, there was no way to measure the elementary particles, and this problem eventually gave rise to the basis of quantum physics; the Heisenberg uncertainty principle. Since there was no way to find out the nature of these particles, people came up with another story, with a mathematical fiction known as ‘Quantum Field Theory’. world technologies we use in today's world, such as hadron therapy, Maglev trains, and quantum solvents. But there was a huge problem. Gravity! In quantum mechanics, all forces are carried by different particles; but according to Einstein’s general relativity, gravity is not like other forces in the universe. Gravity is a theory of geometry; Geometry of space-time itself consists of distances which we need to describe with absolute precision. But in quantum physics, there’s no any way to measure the distance. When scientists tried to invent a new particle for the gravity, their mathematics broke down. That was a big problem. If they could relate gravity to quantum physics and the standard model, they could In Quantum Field Theory, a particle is considered as a point get the theory of everything in space. Electrons are distinguishable points with a certain of our nature. mass and a charge. This theory solved a lot of problems that they had. All the models of particle physics are built upon that. This theory has helped a lot in building the real- PAGE| 40 University of Peradeniya GAUGE Magazine