Posted on 02/09/2007 11:28:07 AM PST by US admirer
Twenty years before most scientists expected it, a commercial company has announceda quantum computer that promises to massively speed up searches and optimisation calculations.
D-Wave of British Columbia has promised to demonstrate a quantum computer next Tuesday, that can carry out 64,000 calculations simultaneously (in parallel "universes"), thanks to a new technique which rethinks the already-uncanny world of quantum computing. But the academic world is taking a wait-and-see approach.
D-Wave is the world's only "commercial" quantum computing company, backed by more than $20 million of venture capital (there are more commercial ventures in the related field of quantum cryptography). Its stated aim is to eventually produce commercially available quantum computers that can be used online or shipped to computer rooms, where they will solve intractable and expensive problems such as financial optimisation. It has been predicted that quantum computing will make current computer security obsolete, cracking any current cryptography scheme by providing an unlimited amount of simultaneous processing resources. Multiple quantum states exist at the same time, so every quantum bit or "qubit" in such a machine is simultaneously 0 and 1. D-Wave's prototype has only 16 qubits, but systems with hundreds of qubits would be able to process more inputs than there are atoms in the universe.
Scientists in the world's many quantum science departments are looking anxiously at whether the demonstration - linked to a computer museum in Mountain View California, will vindicate their work or cast doubt upon it.
"This is somewhat like claims of cold fusion," said Professor Andrew Steane of Oxford University's Centre for Quantum Computing. "I doubt that this computing method is substantially easier to achieve than any other."
Others are more enthusiastic: "I'll be a bit of a sceptic till I see what they have done," said Professor Seth Lloyd of MIT. "But I'm happy these guys are doing it." Lloyd is one of the scientists who helped develop the "adiabatic" model of quantum computing which D-Wave's system exploits - a method which D-Wave believes will sidestep the problems which have restricted progress in quantum computing so far.
"Porn at the speed of thought.........'
mmmmmm....entanglement
"
Slides Rule.... The good old slip stick
http://www.freerepublic.com/focus/f-news/945171/posts
Not really, it would take too long to load.
You're obviously not up on computer security issues, otherwise you would see that your point is totally irrelevant. Yes, quantum computers would not be useful for cracking passwords in the manner you suggest. But it turns out that doesn't matter in the least.
Consider that secure html transmissions could be cracked quite easily, since they depend on public key cryptography and you can crack the prime number private key. Now, you can see in clear text everything transpiring between a person and his or her bank account. Who needs the password, you've got all the account info. You could even insert some transactions while you're at it, since you can appear to be the person who is logged in.
As an added bonus, you can intercept pages where a customer changes the password, or sets up a new account and chooses an initial password.
It would be devastating for a terrorist or just plain criminal to get ahold of a quantum computer. All ecommerce in the world would have to cease immediately, in a manner similar to how they grounded all air traffic during 9/11.
Only this time, you would have to stop all ecommerce until every computer in the entire world was upgraded to have quantum encryption (or at least those that are used for any kind of ecommerce). It would be the end of the world as we know it. At the very least a massive worldwide depression would ensue as every company and individual in the industrialized world cut back over to paper and mail for all transactions and supply chain operations. Productivity rates would be set back 20 years, causing massive hyper-inflation, severe labor shortages, etc.
The interesting point is, if quantum computers are ever invented, we have this problem, since it will be impossible to cut ever computer over to use that kind of encryption overnight. I call this the "quantum computing bootstrap problem." The only way to avoid it is the possibility that they are never invented in the first place.
What if the universe is infinite?
ANSWER: the system would be able to process more than an infinite number of inputs. :)
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