10minus9 interview: Philip Moriarty (Part 2)

In the final part of this interview with Philip Moriarty from the University of Nottingham, we talk about pattern formation in nature, research funding, and find out the one physics problem Professor Moriarty would most like to see solved.

Part one ended with a shortlist of scientific heroes…

• OK, but if you have to pick just one?

Let’s go with Fourier.

• One major theme of your research has been pattern formation- why is this so interesting to you?

Every scientist searches for patterns in their data, whether those data arise from a highly complicated state-of-the-art particle physics detector (generating terabytes of measurements), a simple first year undergraduate experiment on the diffraction of light, or a digital image of a micro-organism.  We spend a lot of time thinking up different ways to represent the data so that the underlying pattern is easier to see. (We plot graphs rather than display the data as columns of numbers for precisely this reason). What really fascinates me – and very many other scientists – is when very similar patterns appear across widely different length scales.

the Cellular network is a pattern appearing in natural structures over a huge range of sizes, from the cells in a piece of cork (a), the hide of a giraffe (b), the Giant's Causeway (c) and the structure of the universe (d)

Order Out Of Chaos

Last night, BBC 4 showed The Secret Life of Chaos, one of the best science documentaries I’ve seen for a long time. In it, they showed the BZ reaction, a chemical reaction resulting in travelling bands of colour- a pattern arising from disorder. I’ve included a brief explanation below, but frankly, this is just cool.

This is a type of autocatalytic reaction. The reaction starts at random points in the chemical mixture, but there is a kind of feedback so that this triggers more reactions at the same place. This spreads out in all directions so you end up with a circular wavefront.

Usually, chemical reactions take place in one direction- A and B react to make C. However, in some special cases, the reaction can oscillate between two states. This can be seen as a mixture changing colour, then changing back in a repeated cycle. So, after one wave has passed through the mixture, other waves follow as the reaction oscillates between two states.

This is an example of self-organisation, a process whereby patterns emerge from disordered systems. It happens everywhere, from the nano scale to the formation of the universe. If you’re really interested, read Philip Ball’s recent Nature’s Patterns series of books (OUP).