You know, this may make me a bad physicist, but quite frankly you can add “quantum computers” right below “zombies” to the list of Inherently Cool Things That I Am Absolutely Sick Of*. Seriously, there seems to be some sort of unstated rule that one third of the weekly colloquia offered by university physics departments need to be on the topic.
Quantum computers, to recap, are computers that are based on quantum mechanical principles. Whereas traditional computers (such as the one on your desktop**) are based upon processing ‘bits’ of information which can be either 0 or 1, quantum computers are based upon processing ‘qubits’ of information, which can be 0,1, or a superposition of both. Thus, two qubits can simultaneously represent 4 different values, three qubits can represent 8, and so on. In practical terms, such a quantum computer would have significant advantages over a classical computer when it comes to performing certain types of calculations. And when I say “certain types of calculations,” understand that what I in fact mean is “factoring large numbers,” which has applications in the field of cryptography, making the quantum computer, potentially, a very powerful code-breaking machine. As very powerful code-breaking machines sound like good things to own, a great deal of money has been poured into developing them. There’s a good explanation to be found here.
And all of that is well and good. Except for just one thing: these quantum computers don’t actually exist as yet, per se***. As such, even though there is a lot of research being done in this field, and therefore a lot of researchers on hand at any given time to deliver lectures on the subject, most of these lectures basically boil down to unpaid hour-long advertisements for how awesome these things will be once they are finally invented. This is something which I, after years of bitter experience, have learned to avoid. Hence the reason that I am camped-out here in my office right now, rather than attending the latest colloquium on the subject.
*Which is more properly known as “the list of Inherently Cool Things of Which I am Absolutely Sick.” A preposition is not something to end a sentence with.
**Or, let’s be honest here, your lap, or perhaps your palm,
***Mind you, if you owned a superpowerful code-breaker…would you announce it to the world?