For a considerable fraction of the students starting grad school in the US, September is a synonym for the dreaded qualifying exams. These tests are meant to check our mastery of undergraduate-level physics, so we can move on and take the graduate level courses with confidence in what we’re doing. Of course, for many students (and for me as well, depending on the day and my level of exhaustion) they rather mean plain torture.
Getting ready for an exam like this involves solving literally hundreds of problems that will cover a wide spectrum of topics in physics: classical and quantum mechanics, relativity, thermodynamics and statistical mechanics, electricity and magnetism, etc.
While doing all these practice tests I wondered about how, sometimes you would have no idea about how to tackle a problem and then, suddenly, something magical happens, you understand.
Montgomery Burns' 1000 monkeys writing on 1000 typing machines.
This rather trivial, everyday event has always intrigued me. Nothing has changed, you’re staring at the paper like you did two seconds ago, but in your head there is a big neon sign saying: “hey, I know what this is about!”
I wonder about what the brain is actually trying to do in those cases, maybe it just dumping all the memories related to problems like the one you’re reading, trying to make something fit. This is probably not so elegant, it would probably make several neurobiologists turn red, and it reminds me a bit of that idea that an infinite number of monkeys hitting keys in typewriters should be able to produce the complete works of Shakespeare, but indeed it’s a mysterious phenomenon.
On a side note, this also reminds me of a great satire about the work of people in academia: “Gulliver’s Travels” by Jonathan Swift. On one of his travels, Captain Gulliver visits an Academy where he is shown a machine that can produce all the knowledge of the world. It’s basically a grid of rotating cubes with words of them; some assistants would rotate the cubes and then take note of the resulting combination of words, then creating “new knowledge”. Here’s a sketch of the machine, from the first edition of Gulliver’s Travels.
Ironically, this great book loaded with tons of dark humor ended up being considered as a book for kids.
No matter what the process involved is, understanding something is one of the great pleasures of physics and, I think, of science in general. Training ourselves to solve these problems should help us in developing our instinct on how to solve other, not so trivial questions that we may encounter during our careers. If we are very lucky, we’ll be able to provide answers or hints to those as well. In a way, it’s very similar to a detective’s job, as Zoe mentioned some time ago.
This pleasure, the pleasure of finding things out as Feynman put it, it’s the driving force for many of us in this field. If the thing you have figured out is very important, you can certainly understand Archimedes’ reaction, running naked down the streets of Syracuse screaming “Eureka!” (I found it!) when he understood what we now call the Archimedes principle. And probably also, more recently, you could understand Kary Mullins pulling his Honda Civic to the side of a Californian road to be able to think about the implications of the idea that made him receive the 1993 Nobel prize in chemistry, and that made him exclaim something that it’s, in a way, close to Archimedes’ Eureka, but I will leave to you to find out.
