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Quantum Computing Breakthrough in Japan
An anonymous reader writes "A research team funded by NEC and RIKEN, Japan's Institute of Physical and Chemical Research, are the first to demonstrate a Controlled NOT (CNOT) quantum gate. The CNOT gate when coupled with a rotational gate would create a universal gate. The universal gate would be the basis for quantum computing. ETA for the first quantum computers: 10 to 100 years." When quantum computers first come to fruition, the best part will be reminiscing about how terrible computers were "back in the day."
Not for a while, but it really does make you wonder. Pretty much all of the strongest encryption we have to date (except huge one-time pads shared between parties) rely on classical crypto: it's all about computational infeasibility of solving certain equations.
Quantum computing does have the potential to make this obsolete. All SSL -- used by banks, governments, might be breakable. PGP would be breakable.
It seems reasonable that governments will tightly control developments in this field once they catch on to what's at stake. IMHO, an enemy with the power to break classical crypto is a much greater threat than a jackass carrying an exacto knife.
Modern schemes wouldn't be necessary because quantum cryptography would become the standard and is proven to be unbreakable by the laws of quantum mechanics.
Doesn't quantum cryptography require a point to point optic channel capable of successfully transmitting individual photons without interfering with their polarization (as well as detectors and receivers for such)? Even if people get fiber optic lines to their homes in the next few decades, I'm pretty sure we'll never see anything like that available to home users. If you want unbreakable cryptography today, you can use a one time pad with less inconvenience.