Computing with Quantum Cats: From Colossus to Qubits

"This is a history of the theory of computation. It introduces all the most important people and you see the development of the ideas. So, first of all, Alan Turing came up with what computation is. Then John von Neumann wanted to design hydrogen bombs and needed a computer to do that. So he took some of Turing’s ideas to design a computer. Then we come to Richard Feynman with quantum physics and David Deutsch and John Stewart Bell. There are little biographies of each of them. Yes. What you don’t get is a good feeling for what quantum computing is, because I don’t think you can get that without doing some mathematics. But if you’re completely math-phobic and you want to read a quantum computing book, this is a very good one for the underlying history and an introduction to the founders of the subject. It’s difficult to say what the applications are going to be. I certainly think that chemistry could become very, very different in the next decade. Probably the most major change is going to be that kids in school are going to be learning about quantum computing and playing with little quantum computers. It’s going to have more of an impact in education, I think. Teleportation is possible and it’s been done many times. What we’re talking about is teleporting the states of qubits. A Chinese team has actually teleported a qubit from Earth to a satellite in low earth orbit. Quantum teleportation is here and it’s used for communication—but we’re nowhere near teleporting people! You should take 2 to the power of the number of qubits and that tells you how many bits you’re talking about. If you’ve got five qubits, that’s the size of one of IBM’s quantum computers: that’s 32 bits. It’s a mixture. A lot of descriptions oversimplify things and say it’s a parallel computation. It isn’t really a parallel computation, because you’ve got all these rules about what happens when you measure qubits and so on. When you learn about quantum computing the first thing you begin to wonder is whether you can actually do anything with it because the rules seem so strange. But in fact you can. There’s work being done on photosynthesis, for instance. You want to be able to convert sunlight into energy—to be stored in batteries, for example. That’s a quantum process and it’s being studied using quantum computers. It really does have potential."