In 1925 two young Dutch physicists, Samuel Goudsmit and George Uhlenbeck, were puzzling over the latest work from famous (and famously acerbic) physicist Wolfgang Pauli. Even the first people to develop the idea of spin thought it had to be wrong. But now a new account of spin may be on the horizon-one that pulls back the curtain and shows how the magic works.
And like any good magician, electrons haven't told anyone how the trick is done. So spin isn't just one of the best tricks that electrons pull it's also one of their most crucial. In fact, there wouldn't be any molecules at all. Without spin, the entire periodic table of elements would come crashing down, and all of chemistry would go with it. You'd collapse, too-and that would be the least of your problems. If electrons didn't seem to spin, your chair would collapse down to a minuscule fraction of its size. Even more surprising is that for nearly a century, this seeming contradiction has been written off by most physicists as just one more strange feature of the quantum world-nothing to lose sleep over.
If electrons actually spun fast enough to account for all of the spinlike behavior they display, their surfaces would be moving much faster than the speed of light (if they even have surfaces at all). They can't spin proving that it's impossible for electrons to be spinning is a standard homework problem in any introductory quantum physics course. Naturally, physicists call this behavior “spin.”īut despite appearances, electrons don't spin. It even has a little magnetic field, just like a spinning object with electric charge should. No matter how an electron is jostled or kicked, it always looks like it's spinning at exactly the same speed. Its spinning never appears to slow or speed up. Every electron ever observed, whether it's just ambling around a carbon atom in your fingernail or speeding through a particle accelerator, looks like it's constantly doing tiny pirouettes as it makes its way through the world. But one of their most impressive tricks is deceptively simple, like all the best magic.
They seem to flit about an atom without tracing a particular path, they frequently appear to be in two places at once, and their behavior in silicon microchips powers the computing infrastructure of the modern world. Electrons are proficient little magicians.
0 kommentar(er)
