In Search of Schrödinger’s Cat – John Gribbin *****
This has to be one of John Gribbin’s best pure science (as opposed to science/biography) books, and has stood the test of time surprisingly well since being written in 1984. Although some of the implications and developments of quantum theory, notably quantum entanglement, have moved on a lot in more recent years, the basics of quantum theory, which this book covers, still apply, as does the historical context which Gribbin does well here.
The cat in question is the one used by German physicist Erwin Schrödinger as an illustration of just how strange (and unlikely) the whole idea of quantum theory was. Because of the way quantum particles that can be in two states simultaneously until they are observed and randomly become one or the other, Schrödinger envisaged a cat in a box that would live or die dependent on a random quantum event. The suggestion was that, until the box was opened, the cat would be both dead and alive at the same time.
It’s probably the best known image from the quantum world, which is rather a pity, as it was intended to demonstrate the inadequacy of the theory, but in practice misrepresents it at anything more than a trivial level. Though there may be arguments about the workings and interpretation of quantum theory, it stubbornly refuses to be dismissed, matching observed effects with impressive consistency.
Quantum theory isn’t easy to explain in a way that is accessible to any reader, and Gribbin isn’t always the world’s best populariser because he does have a tendency to descend into supposedly helpful examples that can be rather baffling, but this book general avoids that trap remains one of the best attempts at getting across the whole astounding business. Liable to leave your head spinning, but that’s not a bad thing.
It might seem a rather petty complaint, but the Black Swan (UK) paperback reviewed was physically decidely poor – coarse paper and printing (with too little space between the lines of text) – it doesn’t change the content, but does detract something from the reading experience!
Gribbin wrote a sequel, Schrödinger’s Kittens, in 1994 which attempts to bring the picture up-to-date. This is rather less successful, in part as up-to-dateness doesn’t last, and in part because it’s not so well structured. Still some interesting points, though.