'Blind' Quantum Computing Proposed For the Cloud 89
judgecorp writes "Researchers at Vienna's Quantum Science and Technology Center have proposed that 'blind' quantum computing could be carried out securely in the cloud. When (if?) quantum computers are developed, they will be very fast, but not everyone will have them. Blind quantum computing will be useful, because it shows that users can encode 'qubits' and send them to a shared quantum computer to be worked on — without the quantum computer having any knowledge of what the data is (abstract). The data also cannot be decoded form the qubit while it is in transit. It's good to know that quantum computers will be secure when they exist. At the moment, of course, they are even more secure, by virtue of their non-existence."
Re:quantum hype (Score:2, Interesting)
As a mathematician not working in the field, let me point out that any AC saying "as a X working in the field" probably deserves to have the rest of his post ignored.
Anyway, the production of quantum algorithms is a routine computer science problem. And the building of a quantum computer is an engineering problem. I'm not really sure what great contribution physics per se is making to quantum computing, i.e. what new science is being discovered and applied to quantum computers, but perhaps you'll enlighten us.
I know that the output is known because otherwise it couldn't be converted to classical form for sending across the 'net to the customer.
Re:quantum hype (Score:4, Interesting)
There are some keywords at TFA that give a hint. The computer is "measurement based", what I'll understand as "the computer only does measurements", also, "without knowing the original states, nobody can decode the output".
Turns out that are infinite ways (normaly over a finite continuum space) to encode your original bits, and if your computer only does measurements, the answer will be encoded the same way you encoded the data. If the computer operators don't know your encoding, they won't be able to read your data.
The hard thing is getting those phothons already encoded through the world into the computer, and getting the results back. Also, the above assumes that you can't discover the encoding, but it doesn't survive known plaintext attacks.