Explaining Life With Physics

In the demon in the machine, Physicist Paul Davies explores an emerging area of research that aims to merge Physics and Biology, to explain how life began

What has physics got to do with the origin of life?

Seventy-five years ago, the famous quantum physicist Erwin Schrödinger gave a series of lectures and then wrote a book called What Is Life? Schrödinger was one of the founders of quantum mechanics, which is probably the most successful scientific theory we have. At a stroke it explained the nature of matter, all the way from atomic nuclei up to stars. So here was an architect of a theory so powerful that it explained the nature of matter. Could it also explain the nature of life?

In his lectures, Schrödinger had to admit that, in spite of his brilliance, he still found life very baffling, looked at through the eyes of a physicist. At the level of individual atoms inside a living organism, it is just standard physics – nobody doubts that. But by the time you get to the level of a living cell, it looks like some sort of magic is going on. It’s so extraordinary, so baffling, the things that life does – all those stupid atoms getting together to do such clever things – that Schrödinger felt that some new type of physics must be involved. He said that we must be prepared to find a new type of physical law prevailing in it. Not just a new law, but a new type of law.

Even 75 years on, and in spite of the extraordinary advances in biology during that period of time, nobody knows what life is or how it began. But I think, just in the last few years, we’ve seen a little crack in the wall of mystery that shrouds life. I think we are now beginning to see what makes life tick.

Why do we need a new type of law? What’s wrong with the physics that we have now?