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Quantum Computing Without Qubits
An anonymous reader shares this interview with quantum computing pioneer Ivan Deutsch. "For more than 20 years, Ivan H. Deutsch has struggled to design the guts of a working quantum computer. He has not been alone. The quest to harness the computational might of quantum weirdness continues to occupy hundreds of researchers around the world. Why hasn't there been more to show for their work? As physicists have known since quantum computing's beginnings, the same characteristics that make quantum computing exponentially powerful also make it devilishly difficult to control. The quantum computing 'nightmare' has always been that a quantum computer's advantages in speed would be wiped out by the machine's complexity. Yet progress is arriving on two main fronts. First, researchers are developing unique quantum error-correction techniques that will help keep quantum processors up and running for the time needed to complete a calculation. Second, physicists are working with so-called analog quantum simulators — machines that can't act like a general-purpose computer, but rather are designed to explore specific problems in quantum physics. A classical computer would have to run for thousands of years to compute the quantum equations of motion for just 100 atoms. A quantum simulator could do it in less than a second."
Look in the sky, see the flock of starlings?
The dark clump of birds that you can see will dart around, sometimes here, sometimes there. It can fly west and yet clump east, time-travel! Must be negative time! Sometimes simultaneously appearing in two places. Faster than light travel! Sometimes no clump can be seen. Where'd they go? Poof, out of existence.
You want a quantum simulator? Starlings, go watch a flock of starlings and apply your quantum equations to their motion.
You may think I'm kidding, but the same problem exists. Just as you can't see the individual bird, only the flock, likewise you've built a bunch of equations for a flock of smaller particles. You can only detect the flock and not the particles.
Keeping with your analogy ... In order to exactly determine the location of each single starling, you need a shotgun(s). Then it no longer is part of the flock now that it has been observed.
As an aside, I am aware that you can shoot at a flock of starlings all day and not hit a one.
*sigh* then why are you reading "News for .." oh fuck, how long has that been gone? *le sigh*
... if you know the computer's speed, you cannot know where the computer is.
I would've preferred "Noble Steed," but I'll take it.
coding is life
I don't believe in real quantum computers because they require operating on the premise you can just sit there and extract whatever unlimited amounts of computation from the universe for a cost exponentially approaching free.
No doubt at all these machines given enough time and effort will work and they will provide the world with useful benefits only those benefits will look nothing like:
"Problems that would take a state-of-the-art classical computer the age of our universe to solve, can, in theory, be solved by a universal quantum computer in hours."
Classified information is purely a product of the government. They can't just classify information produced by citizens (citation: the first fucking ammendment, you dumbass crank).
Actually they can and have done so in the past, primarily in the field of cryptography, a field for which quantum computers might have important applications, so his fears are not unfounded.
If I can be modded down for being a troll, can I be modded up for being an orc, or a balrog?
Einstein never really accepted quantum mechanics. I sometimes wonder if the issues regarding quantum computing are a little more fundamental than technological. Maybe that old genius was smarter than we give him credit for!
http://en.wikipedia.org/wiki/I...
Ewige Blumenkraft.
The proposal for the quantum simulator was made back in 1982
In 2011 paper was already written about the matter
http://arxiv.org/abs/1109.6457
... Einstein invented quantum mechanics and you're an idiot ...
Albert Einstein is one of the guys that I truly respect, but I still gotta say that Quantum Mechanics was not invented by Einstein alone ... Other people such as Max Planck, Niels Bohr, Werner Heisenberg, Louis de Broglie, Arthur Compton, Erwin Schrodinger, Max Born, John von Neumann, Paul Dirac, Enrico Fermi, Wolfgang Pauli, Max von Laue, Freeman Dyson, David Hilbert, Wilhelm Wien, Satyendra Nath Bose, Arnold Sommerfeld, amongst many others, also have contributed to the theory of Quantum Mechanics
Muchas Gracias, Señor Edward Snowden !
"A classical computer would have to run for thousands of years to compute the quantum equations of motion for just 100 atoms. A quantum simulator could do it in less than a second."
...and a hundred atoms can do it in real time!
http://www.geoffreylandis.com
...and then have the laser toting sharks surround them and they'll form a Bose–Einstein flock condensate.
Failure to follow this advice may result in non-deterministic behavior.
The problem is how well solutions scale. Give me 7-bit classical processors, and I can eventually hack them into something bigger. Two 7-qubit quantum processors can't be used to create a 14-qubit one, and making a 14-qubit processor is a whole lot harder than making a 7-qubit one. We're doing better at building these, but it's possible we'll never be able to make, say, a 10K-qubit computer, without running into some limit somewhere, and some proposed uses require that many qubits.
We'll have to see. The things are useful now in some applications, and they'll continue to get better for some time.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes