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First Electronic Quantum Processor Created
ScienceDaily is reporting that the first rudimentary solid-state quantum processor has been created by a team led by Yale University researchers. "Working with a group of theoretical physicists led by Steven Girvin, the Eugene Higgins Professor of Physics & Applied Physics, the team manufactured two artificial atoms, or qubits ('quantum bits'). While each qubit is actually made up of a billion aluminum atoms, it acts like a single atom that can occupy two different energy states. These states are akin to the '1' and '0' or 'on' and 'off' states of regular bits employed by conventional computers. Because of the counterintuitive laws of quantum mechanics, however, scientists can effectively place qubits in a 'superposition' of multiple states at the same time, allowing for greater information storage and processing power."
Honey, I got you these two solid-state qubits that hold their quantum states for a microsecond and can be used to perform rudimentary algorithms.
The enemies of Democracy are
You can find the lab site here with several papers freely available in pre-publication form on arxiv from the researchers. I'm trying to find the "basic algorithms" the article alludes to that these rudimentary processors can perform. I thought only a handful were applicable (Shor's algorithm) to quantum computing. Anyone know?
My work here is dung.
I am not trying to split hairs. This is actually a rather important point: they did not manufacture "two artificial atoms, or qubits". They manufactured two clusters of atoms that acted as qubits.
http://www.nature.com/nature/journal/vaop/ncurrent/pdf/nature08121.pdf
(For those with access to Nature through school or work...)
So in theory, one of the greatest scientific inquiries can now be solved by a quantum computer.
Which came first? The chicken or the egg.
The answer, of course, is 'Yes'.
'Sensible' is a curse word.
Soon a PC with a Quantum Processor, Holographic Memory and optical storage.
Running Duke Nukem Forever on a three dimensional console inside your flying car as it pilots itself to your workplace ...
My work here is dung.
That has been long since solved with evolutionary genetics.
The egg.
What produced it just happened not to be a chicken. Something close, but not quite.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
Why can't people use a real name in Slashdot or Reddit?
I'm sorry you feel that way, Mr. Sybert42.
It is a miracle that curiosity survives formal education. - Einstein
Obligatory slashdot answer on any topic regarding quantum mechanics: Yes and No.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
New question: what came first the dinosaur or the egg?
Doesn't change much does it?
Win a signed Stephen Carpenter ESP Guitar from the Deftones: http://def-tag.com/?r=0008781
Fish.
Ah, so then you agree that it wasn't a chicken egg? ie Chicken came first (from non-chicken egg), then laid chicken egg.
Neither: It was the Rooster who came first (it happens to every guy once in a while).
Authority questions you. Return the favor.
While each qubit is actually made up of a billion aluminum atoms, it acts like a single atom that can occupy two different energy states.
This sounds a like a bose-einstein condensate, where many atoms will act is if though they are all part of a larger, single atom. Also, it gains some pretty interesting properties, neither of which can be described exactly as solid, liquid or gas.
The article didn't mention anything about near absolute zero temps, though.
Fact: Everything I say is fiction.
There's no simulation -- the large group of atoms forms one qubit. That's why this is interesting. Normally, only very small things (like one atom) exhibit quantum behavior. This system is large for something able to exhibit quantum behavior. All the parts effectively join together to act like one quantum system.
640K qubits ought to be enough for anybody
-Billco, Fnarg.com
This idea was invented by Shampoo.
coding is life
Yes the first. The Dwave guys aren't building quantum computers. Their system lacks entanglement between the qubits, which is essential to running quantum algorithms. They have also been less than forthcoming about the coherence in their system.
Slashdot: where don knuth is an idiot because he cant grasp the awesome power of php
No, no, you've got it backwards.
A non-chicken laid a chicken egg (i.e. the egg's genes were those of a chicken), from which hatched a chicken.
I once designed a system around imaginary numbers.
It was too complex.
..baddum tish!
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beware he who would deny you access to information, for in his mind he dreams himself your master
I took a class on Quantum computing, and studied many specific QC algorithms, so I know a little bit about them. A lot of misunderstandings about them, so let me summarize.
Quantum Computers are not super-computers. On a bit-for-bit (or qubit-for-qubit) scale, they're not necessarily faster than regular computers, they just process info differently. Since information is stored in a quantum "superposition" of states, as opposed to a deterministic state like regular computers, the qubits exhibit quantum interference around other qubits. Typically, your bit starts in 50% '0' and 50% '1', and thus when you measure it, you get a 50% chance of it being one or the other (and then it assumes that state). But if you don't measure, and push it through quantum circuits allowing them to interact with other qubits, you get the quantum phases to interfere and cancel out. If you are damned smart (as I realized you have to be, to design QC algorithms), you can figure out creative ways to encode your problem into qubits, and use the interference to cancel out the information you don't want, and leave the information you do want.
For instance, some calculations will start with the 50/50 qubit above, and end with 99% '0' and 1% '1' at the end of the calculation, or vice versa, depending on the answer. Then you've got a 99% chance of getting the right answer. If you run the calculation twice, you have a 99.99% chance of measuring the correct answer.
However, the details of these circuits which perform quantum algorithms are extremely non-intuitive to most people, even those who study it. I found it to require an amazing degree of creativity, to figure out how to combine qubits to take advantage of quantum interference constructively. But what does this get us?
Well it turns out that quantum computers can run anything a classical computer can do, and such algorithms can be written identically if you really wanted to, but doing so gets the same results as the classical computer (i.e. same order of growth). But, the smart people who have been publishing papers about this for the past 20 years have been finding new ways to combine qubits, to take advantage of nature of certain problems (usually deep, pure-math concepts), to achieve better orders of growth than possible on a classical computer. For instance, factoring large numbers is difficult on classical computers, which is why RSA/PGP/GPG/PKI/SSL is secure. It's order of growth is e^( n^(1/3) ). It's not quite exponential, but it's still prohibitive. It turns out that Shor figured out how to get it to n^2 on a quantum computer (which is the same order of growth as decrypting with the private key on a classical computer!). Strangely, trying to guess someone's encryption key, normally O(n) on classical computers (where n is the number of possible keys encryption keys) it's only O(sqrt(n)) on QCs. Weird (but sqrt(n) is still usually too big).
There's a vast number of other problems for which efficient quantum algorithms have been found. Unfortunately, a lot of these problems aren't particularly useful in real life (besides to the curious pure-mathematician). A lot of them are better, but not phenomenal. Like verifying that two sparse matrices were mulitplied correctly has order of growth n^(7/3) on a classical computer, n^(5/3) on a quantum computer. You can find a pretty extensive list by googling "quantum algorithm zoo."
Unfortunately [for humanity], there is no evidence yet that quantum computers will solve NP-complete problems efficiently. Most likely, they won't. So don't get your hopes up about solving the traveling salesmen problem any time soon. But there is still a lot of cool stuff we can do with them. In fact, the theory is so far ahead of the technology, that we're anxiously waiting for breakthroughs like this, so we can start plugging problems through known algorithms.