Tuesday, January 11, 2011

Before the Big Bang: Loop quantum gravity?

Big Bang,Wikimedia Commons

In “The Birth of Time: Quantum Loops Describe the Evolution of the Universe” (ScienceDaily, Dec. 17, 2010), we learn
What was the Big Bang and what happened before it? Scientists from the Faculty of Physics, University of Warsaw have attempted to answer the question. Within the framework of loop quantum gravity they have put forward a new theoretical model, which might prove useful for validating hypotheses about events prior to the Big Bang. This achievement is one of the few models describing the full Einstein's theory and not merely its greatly simplified version.
The model invokes quantum loop gravity:
The real answer to the mystery of the Big Bang lies in a unified quantum theory of matter and gravity. One attempt at developing such a theory is loop quantum gravity (LQG). The theory holds that space is weaved from one-dimensional threads. "It is just like in the case of a fabric -- although it is seemingly smooth from a distance, it becomes evident at close quarters that it consists of a network of fibres," describes Wojciech Kaminski, MSc from FUW. Such space would constitute a fine fabric - an area of a square centimetre would consists of 10^66 threads.
Question: If unified quantum theory is the real answer to the mystery of the Big Bang, won’t it end up being the next mystery? Of course, that will hardly be bad for the people who developed the theory.

It’s a bit difficult to picture a one-dimensional string, but we keep trying.