Question: What is string theory? Is that something you are researching into?

David Freeborn answered on 17 Jun 2013:

String Theory is an attempt to create a Grand Unified Theory of everything- a single theory that describes all the forces of the Universe. Currently, we don’t know whether it’s right or wrong, because it’s extremely difficult to experimentally test. Worse still, there are several hundred different versions of the theory, so even if it is right, we don’t know which version is!

The idea is that at the smallest scale (0.00000000000000000001 metres approximately), space and time are not smooth, but composed of tiny “strings” or “loops”. These strings can vibrate in different ways, and the different forms of vibration of the string correspond to the different particles of the Universe. The different versions of string theory describe different shapes the strings might take.

Some scientists think it is so difficult to test (we’d need much, much better equipment), it doesn’t really count as science at all. Some physicists don’t think it can be tested at all because there are so many possible types of string theory.

Most of my research isn’t on string theory- there are lots of possible alternatives, but some of my colleagues do work on it. It’s a very interesting area of research.