On this episode of Our Island Universe: The hunt for the holy grail of a unified theory of everything.
Host: Shanil Virani, Director of the John C. Wells Planetarium Harrisonburg, VA.
Follow on Twitter as shanilv
Transcript:
Albert Einstein's Theory of General Relativity turned 100 years old in 2015. This theory of gravity describes the Universe on large scales and has passed every test astronomers have put it through with flying colors. In fact, there is not one observation in the cosmos that put it at odds with Einstein's Theory of General Relativity. But in our heart of hearts, we know this theory is wrong.
Quantum Mechanics, that other triumph of 20th century physics, works spectacularly well at describing nature on the smallest scales, the size of atoms and smaller. This theory of physics is also approaching 100 years in age and has ushered in our technological revolution that allows the phone in your hand to store gigabytes of information. But in our heart of hearts, we know that this theory is also wrong.
There are apparently 4 fundamental forces in nature: gravity, electromagnetism, the weak nuclear force, and the strong nuclear force. The weak nuclear force is responsible for radioactive decay, and the strong nuclear force is responsible for binding nuclei together. The "holy grail" of physics is one theory to unite them all - a Theory of Everything. This theory would describe nature at both the largest and smallest scales, and would likely provide insight as to what dark matter and dark energy are. It may also help us understand what exactly happens inside a black hole. Three of the 4 forces have been unified but we are still struggling to include gravity. Ideas like string theory and loop quantum gravity are attempts to unify quantum mechanics and general relativity but have yet to be experimentally confirmed. Until that time, these 2 pillars of 20th century thought remain waiting for that Theory of Everything.