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Fredkin Gate Breakthrough Brings Quantum Computing Within Closer Reach (pcworld.com)
An anonymous reader quotes a report from PCWorld: Quantum computers are based on atomic-scale quantum bits, or qubits, that can represent both 0 and 1 simultaneously. Realizing that potential, however, depends on the ability to build working quantum circuits. The quantum version of the classic Fredkin gate exchanges two qubits depending on the value of the third. It could be a key component of quantum circuitry, but because of the complexity involved, no one has ever managed to build one in the real world -- until now. Whereas the Fredkin gate typically requires a circuit of five logic operations, researchers from Griffith University and the University of Queensland used the quantum entanglement of particles of light to implement the controlled-SWAP operation directly. Essentially, the scientists demonstrated how to build large quantum circuits directly, without having to use numerous small logic gates. That, in turn, puts real quantum computers within closer reach.
Quantum computing can be described as a method, a technique, which allows for the computer for a given task to take a peak into the future and to read the answer from the future back to the present.
This is completely wrong. There are in fact computational models that have been worked out about what a computer that could peak into the future would be like and they are insanely more powerful than quantum computers. See http://www.scottaaronson.com/papers/ctc.pdf. Quantum computing has nothing remotely like what you've said. I suggest for an actual primer on the topic reading Scott Aaronson's excellent book "Quantum Computing Since Democritus" which doesn't require anything beyond a little basic linear algebra. And in the meantime, if you don't know much about a topic, maybe don't make extreme policy suggestions?
Alternatively, this video does a reasonable job at outlining how a quantum computer works. It doesn't go into too much detail, but it's probably enough to give the average person an idea of the differences between quantum and classical computers.