Quantum Algorithms
Wednesday, March 31, 2004
Qudit Simulator...in Visual Basic
It's not the coding envirionment I would personally choose for this, but no matter, someone has written a Qudit simulator in Visual Basic. (A qudit is a 'D' dimensional quantum unit, i.e. a qubit is 2-dimentional, qutrit 3-dimentional.)
Tuesday, March 30, 2004
Single Molecule Logic Gates
In Molecular logic proposed, researchers explore single molecule logic gates. They don't seem to take advantage of entanglement, so it's a nanocomputer idea, not a quantum computer in the usual sense. "Practical applications for molecular electronics are more than a decade away."
Bennett and Shor on Quantum Channel Capacities
Two big names together in one paper: Quantum Channel Capacities, Bennett CH, Shor PW. It appears in Science, but unfortunately seems to be one of the few quantum papers to not be found at arxiv.org.
Wednesday, March 24, 2004
Easy Quantum Circuit Drawing
Michael Nielsen posts: "Ike Chuang has just released a package enabling quantum circuits for quantum computers to be drawn easily (link.)"
Monday, March 22, 2004
Bjarne Stroustrup on AT&T/Bell Labs
I asked Dr. Stroustrup to elaborate on what he said in this article (see previous post) about some advantages AT&T Bell Labs had over universities, and he replied:
"I don't really want to be dragged into a debate, but think of this: AT&T Bell labs had 1,000 hand-picked PhDs concentrated in a few interrelated areas supported by development organizations consisting of many thousand good engineers (all with masters degrees). A good university department has maybe 30 to 60 PhDs, many closely focussed on getting tenure. It's a world of difference, except that the AT&T Bell Labs I describe no longer exists."
I also asked what specific reward mechanisms AT&T Bell Labs had that universities don't, and he replied:
"The reward mechanisms were just one thing, but compared to universities, there were a significantly higher emphasis (read money, status, job security) on doing something radically different, clean, but practical. The chance to see your work on a world scale was a huge motivator. The absence of "publish or perish" was a huge factor in being able to keep your eyes on the ball for years, rather than having to follow the raise and fall of fads and fashions. A very open community where you could always find someone really smart and experienced to discuss new ideas with was in itself a reward and a motivator. There's simply nothing like it. if you haven't seen it, you probably wont understand or believe it. And then you didn't have to struggle for promotion: staying technical was a real option.
I use the past tense thinking about AT&T Bell labs (and before that Bell telephone Labs, Inc.) at one of its heights - trying to stay out of the debates about the present at AT&T Labs and Lucent bell Labs."
(Thanks to Dr. Stroustrup for the prompt and thorough reply)
AT&T Labs Brain Drain
Slashdot links to: Talent leak drains AT&T think tank. The article gives a sense that the whole (AT&T Labs) was greater than the sum of the parts (former AT&T researchers dispersed among academia posts). This will only be proven false if academic institutions can begin to make AT&T/Bell Lab size impacts on the world, i.e. coming up with the "next" Unix/C/C++, Shor's algorithm, Grover's algorithm, transistor.
I would like to know more about the management and reward mechanisms employed at AT&T/Bell Labs in their heyday (alluded to by Dr. Stroustrup in the article) and see how they contrast with the modern research university.
Friday, March 19, 2004
HAIT Journal of Science and Engineering
New Journal: HAIT Journal of Science and Engineering. According to Open Access News, this new journal's "first issue features extensive papers on nanophysics and quantum information."
True Random Number Sequences Online
This Press Release states: "The University of Geneva and the company id Quantique team to launch the first web site offering the possibility to download random numbers from quantum origin." The actual generator interface is here.
Wednesday, March 17, 2004
Monday, March 15, 2004
World Wide Telescope
In [cs/0403018] The World Wide Telescope: An Archetype for Online Science, researchers Jim Gray and Alexander Szalay predict: "The World-Wide Telescope (WWT) will emerge from the world’s online astronomy data. It will have observations in all the observed spectral bands, from the best instruments back to the beginning of history...Today, you can find and study all the astronomy literature online with Google™ and AstroPh. In the future you should be able to find and analyze the underlying observational data just as easily."
Sunday, March 14, 2004
BBC Audio Interviews
The BBC has created a site with many short audio interviews, including a two minute clip with Werner Heisenberg. Let's hope they put more of the interview online eventually, and add many more like it (link via Neat New Stuff).
Saturday, March 13, 2004
Quantum Crypto Reaches 150 km
optics.org, News: "NEC’s record-breaking system relies on planar lightwave circuit (PLC) technology and a low-noise photon receiver....The system’s second plus-point is an alleged ten-fold increase in signal-to-noise ratio compared with current systems. This is largely thanks to the receiver’s increased sensitivity to photons that have been broadened by dispersion in the long fiber-optic link."
Thursday, March 11, 2004
Single Atom Entangled With a Single Photon
In Nature's free section (reg required), Quantum computing gets a step closer: Researchers have created the flying qubit: "Chris Monroe and colleagues from the University of Michigan used a cadmium atom trapped in an electric field to ‘store’ information about the atom's magnetic state. By pumping energy into the atom with a laser, they forced it to spit out a packet of light. That photon carried an imprint of the atom's information with it, which could be read by a detector."
Wednesday, March 10, 2004
Another MagiQ Story
In BBC NEWS: Quantum codes debut in real world, MagicQ's CEO Bob Gelfond said "his company was working on quantum memory chips, single photon sources and quantum repeaters to help with its long-term goal of creating a commercial quantum computer."
Tuesday, March 09, 2004
Business Week on QC
In Putting The Weirdness To Work, Business Week has their run-of-the-mill quantum computing overview article. Nothing new here, except one interesting tidbit: "The Pentagon's Defense Advanced Research Projects Agency is now beginning a major effort to construct a working quantum information processor." That's interesting, because DARPA's Deputy Director, Robert Leheny, was very pessimistic about Quantum Computing in this interview. (See Peter Shor's response to his doubts here.) Either Leheny's changed his tune, or maybe he'll play the pointy-haired-boss role to scientists involved in the project. But another implication is, the George Bush budget proposal only had about $16 million earmarked for Quantum Computing, but now that DARPA's on board with their project, does that mean that they'll end up with most or all of this money, as opposed to universities who have been working on this stuff for years?
Monday, March 08, 2004
Berkeley Groks
"Berkeley Groks is a weekly radio science program broadcasting on KALX 90.7 FM in Berkeley, CA." Very college-radio-ish (because it is), but they interview Nobel Laureates, other eminent scientists, plus people like Stephen Wolfram. They don't have enough hard drive space for a complete mp3 archive of their shows, but an interesting selection is available here.
Friday, March 05, 2004
David Deutsch's Lectures on Quantum Mechanics
Check out David Deutsch's Video Lectures on Quantum Mechanics. Only lecture 1 is there now (Quantum Computation)...hard to tell if this is a series in the making or if it's the scraps of an abandoned project.
Thursday, March 04, 2004
New Laser Cooling Technique
PhysicsWeb - Making atoms cooler: This technique is notable because apparently "it preserves the quantum state of the atoms."
Update [5-Mar]: Here's the actual paper.
Tuesday, March 02, 2004
UK Gov Backs Quantum Key Exchange
Government backs quantum cryptography: "The [UK] government is putting its weight behind quantum cryptography as a key way of making communications hack-proof...It's not going to replace Secure Sockets Layer in a hurry; it's still a long way away before it becomes practical"
Black Holes May Preserve Information After All
With help from string theory, (Newswise:) Study May Solve One of Great Mysteries of Black Holes: "Since Mathur’s conjecture suggests that strings continue to exist inside the black hole, and the nature of the strings depends on the particles that made up the original source material, then each black hole is as unique as are the stars, planets, or galaxy that formed it. The strings from any subsequent material that enters the black hole would remain traceable as well."
Monday, March 01, 2004
Bill Gates on QC
From MIT Technology Review, The Ultimate Change Agent, Bill Gates mentions in a speech: "[Microsoft's quantum computing group's work most likely] won’t result in anything in the next decade--and there’s a reasonable chance that it won’t result in anything at all. Now if it does result in something, it’s mind-blowing, because it’s just a different paradigm for computing."