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Having watched The Prestige on Sunday night I feel that there should be lots of bloggable material in it, but I can’t quite put my finger on anything. For those who haven’t seen it, or read the book, it concerns a couple of rival magicians who are obsessed with out-doing each other and pulling off the ultimate magic trick – to the point where one of them gets physicist and engineer Nikola Tesla to build him a teleporter.

Although teleportation can be achieved  don’t expect to see any human (or cat, or hat) teleporter, however imperfect, come on the market any time soon. This phenomenon is currently restricted experimentally to the most simple quantum systems, such as electrons and small atoms.

Nikola Tesla, of course, gets portrayed as a mad scientist. You know when someone’s a hit with the public when their fictional exploits are better known that their factual ones, and Tesla I think falls into that category. Mind you, he did get to play with some serious large voltages in his work, and perhaps it’s surprising that he didn’t manage to electrocute himself.

One nice piece of physics that does come out in the film (but you’d probably have to be a physicist to spot it) is inductive power transfer. This is where you can power things with no wires – such as the field of light bulbs in the film. Here Faraday’s law of electromagnetic induction is exploited. A moving magnetic field is able to induce a voltage around a circuit, which can then drive an electric current. Inductive power transfer has its niche applications at the moment – such as in an induction cooker. Here, electric currents are induced in the metal saucepan on the cooker element, and this current heats the pan, which heats the contents. The element itself doesn’t heat up greatly, except through conduction of heat back from the warm saucepan, so you don’t burn yourself if you put your hand on the element.  A neat idea.

There’s also the possibility of inductive transfer of power replacing the power cords and plug sockets in a domestic house – for example see the summary in PhysicsWorld.