Free Thought
Experimental Realization of an Optical One-Way Barrier for Neutral Atoms
"[A] realization of Maxwell's demon [that] has important implications for cooling atoms and molecules not amenable to standard laser-cooling techniques."
(tags: physics articles science experiment news atoms optics)
Spatially Resolved Observation of Dipole-Dipole Interaction between Rydberg Atoms
A possible mechanism for making a quantum computer with neutral atoms.
(tags: science quantum physics articles news experiment)
High-Fidelity Gates in a Single Josephson Qubit
"By carefully separating out gate and…
One of the most amusing things about writing a blog is that people you've never met form an impression about you from your blabberings, and then, often, when they actually meet you they are astounded that you aren't "an old grumpy guy" or whatever image they had in their mind. So, in order to confuse you even more, here are some things which I've been reading and thinking about and doing while not working on efficient quantum algorithms for the hidden subgroup problem.
Spanish Treasury to Exclude Italian Government Bonds. Could this be an indication of problems ahead for the Euro?…
Designed and built by IBM, at a cost of some $130 million, Roadrunner is the world's fastest supercomputer. It contains 12,960 IBM PowerXCell 8i central processing units, 6,480 AMD dual-core processors, and occupies nearly 6,000 square feet at the Los Alamos National Laboratory in New Mexico.
Roadrunner will primarily be used to simulate the behaviour of nuclear weapons, but will also be used for astronomy, genomics and climate change research. Last weekend, to put it through its paces, researchers ran a program called PetaVision, which models more than 1 billion neurons and trillions of…
So, I've finally had some time to get back to the linear programming
followup. You might want to go back and look at the earlier post to remember what I was talking about.
The basic idea is that we've got a system we'd like to optimize. The constraints of the system are defined by a set of linear inequalities, and
we've got a linear expression that we'd like to maximize.
So, for example, we could have a factory which is capable of producing two
different kinds of widgets. The factory has a maximum capacity of what it can
produce of 300 widgets per day. It gets a supply of metal and plastic…
Working memory - the ability to hold information "in mind" in the face of environmental interference - has traditionally been associated with the prefrontal cortices (PFC), based primarily on data from monkeys. High resolution functional imaging (such as fMRI) have revealed that PFC is just one part of a larger working memory network, notably including the parietal cortex, which has long been the focus of research in the visual domain, and is primarily thought to carry out spatial computations.
What role might such spatial computations have in working memory? Wendelken, Bunge & Carter…
Asking the Wrong Questions: Braaaaaaains
"I've been on the lookout for other works which, like Proof, feature characters whose lives are lived primarily in the mind, and who view the world, and interact with it most fully, through their intellect."
(tags: books literature science culture society)
Everyday Scientist » Plaigiarise an American? The French would never do that!
"Check out the papers yourself to see just how low people can go in science." Disgusting.
(tags: science plagiarism ethics physics optics journals publishing academia)
The Intersection: Science and the Entertainment…
Another SCONC event:
RENCI to Show the Power of Visual Communications at Lunchtime Bistro:
The Renaissance Computing Institute (RENCI) invites the public to a Renaissance Bistro lunchtime demonstration and lecture from noon to 1 p.m. Thursday, June 26 in the Showcase Dome room at the RENCI engagement center at UNC Chapel Hill.
The Bistro is free and includes lunch on a first-come, first-served basis.
RENCI experts, Eric Knisley, 3D visualization researcher, and Josh Coyle, new media specialist, will demonstrate three-dimensional visualizations and interactive touch screen displays. Attendees…
In part I, I wrote about my first semester of teaching on-line and talked about our challenges with technology. Blackboard had a database corruption event during finals week and I had all kinds of struggles with the Windows version of Microsoft Excel. Mike wrote and asked if I thought students should be working more with non-Microsoft software and what I thought the challenges would be in doing so.
I can answer with a totally unqualified "it depends."
First, I think knowing how to use a spread-sheet program is an advantage in many different kinds of fields and even in real-life, outside of…
The Large Hadron Collider is finally turning on.
A quick step backwards: the LHC is a particle accelerator, the largest of its kind, underwritten by all the wild money in science, a ringed tunnel some 27 kilometers long, deep underground, crossing the French-Swiss border at four points. It's been over twenty years in the making and has garnered the support of 10,000 scientists in 85 countries behind its unimaginable modus operandi: to recreate the environment of our universe as it was less than a millionth of a second after the Big Bang, and hence to reveal, among other things, the…
From the Uncyclopedia entry on computers:How Computers Work
Inside a computer case is a midget that intakes power and outputs graphics. On an average computer, this is an average male midget. High end computers contain baby giraffes or sometimes Links (which will periodically shut down, some blame this on power consumption, but this is actually due to the Links leaving the computer in order to save Zeldas from Gilbert Gottfrieds). Cheaper Hewlett-Packard computers generally come standard with a retard midget. Macs and Dells run on magnets which make them better then anything else! Rumors have…
Dude, can I get a Canadian aerospace company to win a United States federal contract and as a consequence have to fund my quantum computing research?Dalhousie research is taking a quantum leap into next-generation computing.
The university has received $2 million from Lockheed Martin that will benefit the university's basic scientific research in an area of quantum computing, physics and material sciences.
The money, to be spread over four years, is part of the company's commitment to spend $242 million in Atlantic Canada as part of its industrial benefits obligation arising from the federal…
Solve Puzzles for Science | Fold It!
Protein Folding: The Game! It has to be better than listening to seminar talks about it...
(tags: chemistry games science computing internet news)
Solar System Visualizer
Look at those planets and moons go!
(tags: astronomy planets science computing internet gadgets)
Polar vortex replicated in a bucket - physicsworld.com
"The centre of the vortex is usually circular, but occasionally it assumes a triangular or even a square shape. Now researchers in Canada claim to have replicated this behaviour for the first time in the laboratory -- using nothing more than water in a c
(tags: science physics pictures news)
The Quantum Pontiff : In Probability We Trust?
"How well has classical probability theory been tested?"
(tags: physics…
The mothership, aka Seed magazine, has a crib sheet for quantum computing. Its not half bad, considering how bad things like this can go. And of course this is probably due in part to the fact that they list the Optimizer as a consultant. But the real question is whether that little shade of black outside of NP is an illustrators trick or the result of a complexity theorist being the person they asked to vet the cheat sheet?
When discussing ways that quantum computing may fail, a common idea is that it may turn out that the linearity of quantum theory fails. Since no one has seen any evidence of nonlinearity in quantum theory, and it is hard to hide this nonlinearity at small scales, it is usually reasoned that these nonlinearities would arise for large quantum systems. Which got me thinking about how to well we know that quantum theory is linear, which in turn got me thinking about something totally wacko.
For you see I'm of the school which notes that the linearity of quantum theory, if broken, almost always…
New leader at the Perimeter Institute this Friday, Perimeter researcher wins prestigious award, a summer school on quantum cryptography, the answer is not quantum physics, and quarter charge quasiparticles for quantum computing.
Looks like the Perimeter Institute, without whom jobs in quantum computing theory would be scarcer a Wii at Christmas time, is going to announce its new executive director this Friday, May 9.
In other Perimeter Institute quantum computing news, Raymond Laflamme, has won the Premier's Discovery Award. The picture on that announcement makes Ray look very intense!…
Closure in an Ethics Case :: Inside Higher Ed :: Higher Education's Source for News, and Views and Jobs
Common sense prevails, for once
(tags: academia ethics stupid)
Ohmigosh fonts
A big step up from Comic Sans
(tags: comics computing silly language)
Jacks of Science â Using Adobe Photoshop for Research and Profit
"As you can see, Photoshop is such a powerful tool it's no wonder it cost $1000 to purchase!"
(tags: science statistics pictures computing silly)
Déjà Vu Dining - New York Times
""Surprisingly decent" was the consensus among nine reviewers who visited chain restaurants in…
One of the coauthors on the paper which I claimed was shoddy has written a comment in the original post. Which merits more commenting! But why comment in the comment section when you can write a whole blog post replying!
The paper in question is 0804.3076, and the commenter is George Viamontes:Dave, this is a complete mis-characterization of the paper. Before I start the rebuttal, I'll add the disclaimer that I am the second author of the paper, and would be more than happy to clarify this work to anyone.
Sweet! Continuing:We are absolutely well aware of the threshold theorem and we even…
Hoisted from the comments, Rod saysYou guys are much more blunt than I usually am (except with students :-). You're also a lot more succinct.
This particular paper may be wrong, and the authors should be told that, but: as the field grows, and more engineers join, there are going to be more people who start with naive positions. The goal is not to run them off, but to teach them, so they can help us build these things :-).
To which, of course, I can only plead guilty, guilty, guilty. I mean no harm to engineers, that is for sure, especially considering the fact that I am surrounded by them…
Okay, well apparently the paper arXiv:0804.3076 which I mentioned in the last post is being picked up by other bloggers (see here and here as well as here) as a legitimate criticism of quantum computing. So before anymore jump on this bad wagon let me explain exactly what is wrong with this paper.
THE PAPER DOESN'T USE FAULT TOLERANT CIRCUITS.
Hm, did you get that? Yeah a paper which claims thatWe will show, however, that if even a small amount of imprecision is present in every gate, then all qubits in every code block will be affected, and more importantly the error in any given qubit…