The central library in my home town of Sydney is giving away books – not just any old books, but those that have never been borrowed. Sadly, but not surprisingly, many of them are scientific books. Browsing through the heap, I was thrilled to find a copy of Enrico Fermi’s original lecture notes on nuclear physics, delivered at the University of Chicago in 1949.
The names of Fermi and Chicago are inextricably intertwined, since it was here that he directed the construction of the first atomic pile, built in a former rackets court under an old stand in the university’s abandoned football stadium. But that was not the only reason why I was thrilled. I was also excited because Fermi is one of my heroes, with a lateral way of thinking that still takes my breath away.
Let me give you an example. When Fermi was an undergraduate studying chemistry, he and his friends were given a mixture of powdered inorganic salts and told to analyze it. The standard way of going about this would be to dissolve the salts in water (all were soluble) and try a series of chemical reactions to test for different elements and chemical groups.
Fermi’s approach was rather different. He put the mixture under a microscope and examined the individual tiny crystals, noting their shapes and colours – particularly their shapes. In this way he quickly narrowed down the possibilities, and refined his list with arguments such as “well it could be this or that, but that is very expensive and they wouldn’t give it to an undergraduate, so it must be this.” Within twenty minutes he had identified the seven different compounds in the mixture, to the amazement of the tutor.
Fermi eventually became one of the world’s leading theoretical physicists, and had a trick that I have only ever been able to emulate in a very minor way. He worked out that almost all of the problems in theoretical physics could be recast to fit into just one of seven possible types, and trained himself thoroughly in mastering the ways of solving the seven different types of problem. With this weapon in hand (about which I have never been able to find the precise details) he was able to conquer almost any physics problem, sometimes at an astonishing speed.
What a man. Now I must go to his book and work out if I can solve even one of the problems that he set. Wish me luck.