Okay this one from ScienceDaily made my day. No it made my week. The title is “Police Woman Fights Quantum Hacking And Cracking.” Intriguing, no? Who is this mysterious police woman in quantum computing? I don’t know many police offers involved in quantum computing, but yeah, maybe there is one who is doing cool quantum computing research (“cracking?” and “hacking?” btw.)
I open up the article and who is the police woman? It’s Julia Kempe! Julia was a graduate student at Berkeley during the time I was there, a close collaborator of mine, and well, last time I checked, Julia described her job as “a senior lecturer (assistant professor) at the School of Computer Science at Tel-Aviv University” not as “policewoman working on quantum hacking and cracking.” And here I was hoping that we’d have someone to arrest anyone making false claims about quantum mechanics!
Asteroids!
A widget to watch out for wayward asteroids:
JPL’s Asteroid Watch Widget tracks asteroids and comets that will make relatively close approaches to Earth. The Widget displays the date of closest approach, approximate object diameter, relative size and distance from Earth for each encounter. The object’s name is displayed by hovering over its encounter date. Clicking on the encounter date will display a Web page with details about that object.
The Widget displays the next five Earth approaches to within 4.6 million miles (7.5 million kilometers or 19.5 times the distance to the moon); an object larger than about 150 meters that can approach the Earth to within this distance is termed a potentially hazardous object.
Available for Mac OS X Dashboard and Yahoo! Widgets.
Also you can follow along in the near eath encounters via twitter by following @AsteroidWatch.
Novel Torrent Technology For arXiv Archives?
Since it seems that the “arXiv on your hard drive” is dead I’ve been thinking a bit about if there is a better way to achieve the goal of distributing archives of the arXiv.
One thing I liked about the “arXiv on your hard drive” was that it used BitTorrent. This could alleviate some of the bandwidth pain associated with distributing the arXiv widely. But of course, one of the problems with using Torrents to distribute the arXiv is that, well, the arXiv changes daily! One solution to this is to update the torrent periodically, but in these go-go times this seems wrong. It seems to me that what we need is a BitTorrent-like protocol for collections that periodically get updated. A seeder could then update its collection and propagate only these new results to other hosts. Does anyone know if such a technology exists? A quick scan didn’t locate anything.
Of course then one would have to convince the arXiv folks to go along with this, but it would seem to me that the bandwidth costs for them could be made really fairly minimal.
Help Rod With His Summer Reading
Rod Van Meter is in search of some summer reading:
I’m feeling the need to recharge my store of ideas, and I have the
nagging feeling that my lack of currency in a bunch of fields is
causing me to miss some connections I could use in my own research.
So, I’m looking for a reading list of, say, the one hundred most
important papers of the decade. It doesn’t have to be an even
hundred, but I’m looking for a good summer’s reading. (Given that
it’s mid-2009, now would be a good time to start composing such a list
anyway, depending on where you want to place the “decade” boundary.)
I want these papers to cover *ALL* fields of computer science and
engineering; I am by nature catholic in my reading.
Head over to his site and help out with your favorite gem of CS/engineering!
OMG QIP=PSPACE!
Today on the arXiv an new paper appeared of great significance to quantum computational complexity: arXiv:0907.4737 (vote for it on scirate here)
Title: QIP = PSPACE
Authors: Rahul Jain, Zhengfeng Ji, Sarvagya Upadhyay, John Watrous
We prove that the complexity class QIP, which consists of all problems having quantum interactive proof systems, is contained in PSPACE. This containment is proved by applying a parallelized form of the matrix multiplicative weights update method to a class of semidefinite programs that captures the computational power of quantum interactive proofs. As the containment of PSPACE in QIP follows immediately from the well-known equality IP = PSPACE, the equality QIP = PSPACE follows.
This solves a long standing open problem (we can say long standing in quantum computing when we mean less than nine years because our field is so young.) It has always been known that PSPACE is in QIP, but prior to this result (assuming its correct: I just downloaded the paper and am starting to read it now) the best known inclusion in the other direction was that QIP is in EXP (this result is due to Kitaev and Watrous.) But wait a second, what the hell are all these letters representing?
Continue reading “OMG QIP=PSPACE!”
Seeing the Kingdom of God on the arXiv
A new entry in the best title every contest, arXiv:0907.4152:
Born Again
Authors: Don N. Page
Abstract: A simple proof is given that the probabilities of observations in a large universe are not given directly by Born’s rule as the expectation values of projection operators in a global quantum state of the entire universe. An alternative procedure is proposed for constructing an averaged density matrix for a random small region of the universe and then calculating observational probabilities indirectly by Born’s rule as conditional probabilities, conditioned upon the existence of an observation.
WWJD? Not quantum Born’s rule, apparently.
Diary of a Sad Physicist
Writing a blog is for me (1) amusing and (2) amusing. Can anyone take anything that I write on a blog seriously? Well sometimes people do. Many eons ago (okay, I lie, it was 2005), I wrote a post about the then new “h-index.” The h-index is an attempt at trying to find a better way of “ranking” citation counts. As such, it is, of course, nothing more than another meter stick in the long line of lazy tenure committee metric sticks. But it’s also fun! Why is it fun? Because calculating any “metric” is fun for people like me who spent their childhood involved in such mind expanding tasks as counting the number of loads of wood we did before we finished stacking all that had been cut. But that’s just me.
Sadly, for others my original post provoke an amazing amount of hatred and anger. Thus is the diary of “Sad Physicist.” Did I endorse this index as the ultimate answer to life, the universe, and tenure. Of course not. What do you take me as, an academic bent on analyzing everything within sight through the eyes of Science! Pfft.
Okay, you ask, well why am I writing about this subject now? Well today, after over three years, the Sad Physicist, the one commenter of most venom about that post, has reappeared! Welcome back friend! So I thought it would be a good chance to collect the original dialogue, you know for posterity. Maybe one could even count this article as a citation, thus increasing Sad Physicist’s h-index! Always helpful, the pontiff is.
Continue reading “Diary of a Sad Physicist”
Various and Sundry
Two notes from Caltech of interest:
- Michael L. Roukes’ group at Caltech has produced a NEMS (nanoelectromechanical system) device which can (almost) measure the mass of a single molecule (as opposed to the many tens of thousands (is this the correct amount?) needed in mass spectrometry.) Build a 2 micrometer by 100 nanometer NEMS resonator. Drop a molecule on it. The frequency of vibration of the NEMS resonator changes. Detect this frequency change. Of course vibration frequency also depends on where the molecule lands. So run the experiment about 500 times to get good estimate of the mass. Future (all ready prototyped) work should alleviate the problem of where the molecule lands causing a need for repeated experiments. From the press release:
Eventually, Roukes and colleagues hope to create arrays of perhaps hundreds of thousands of the NEMS mass spectrometers, working in parallel, which could determine the masses of hundreds of thousands of molecules “in an instant,” Naik says.
As Roukes points out, “the next generation of instrumentation for the life sciences-especially those for systems biology, which allows us to reverse-engineer biological systems-must enable proteomic analysis with very high throughput. The potential power of our approach is that it is based on semiconductor microelectronics fabrication, which has allowed creation of perhaps mankind’s most complex technology.” - Hawaii beats Chile as site of new Thirty meter telescope.
For the past few months I’ve been getting back into shape by running my rear end off. On these jaunts, when I’m not in the mood for KEXP (they stream check them out!) I try to fill my head with something that isn’t mind numbingly dumb (read most radio stations.) Good podcasts include EconTalk where you get to hear about the dismal science. The interviewer, Russ Roberts, has a very strong libertarian (Austrian school) bent, but even when he disagrees he does ask the questions. I think we get to call it the dismal science because a recent interview was on “The Rational Market.” Apparently economists believe that the economy can pass the Turing test! Anyone else have good recommendations for non brain dead podcasts?
Speaking of finance, the Information Processor has two posts up that are worth looking at: Against Finance and Goldman apologia. The lesson of this financial crisis (and LTCM and…) is that when Goldman comes knocking at your door with a deal, run, don’t walk screaming for the door!
Nate Silver has gotten sick of climate skepticism and the daily weather report, and so lays down some money for those who want to bet against average weather statistics. Time to see if I can find a hometown where the weather instruments have been recently changed.
Moonquakes
As someone who was born on a lunar eclipse (explains a lot, no?) the 40th anniversary of man walking on the moon has a special place in my heart. Okay, that sentence makes no sense (I was born on a lunar eclipse however), but anyway everyone is all abuzz about the anniversary of the moon landing so it’s as good as any sentence to let me talk about booming sand dunes.
Booming whah?
Continue reading “Moonquakes”
The Great Firewall of Collaboration
A fellow quantum computing researcher of mine recently joined FriendFeed. Along with another researcher we got involved in a discussion about a paper concerning a certain recent claimed “disproof of Bell’s theorem.” (arXiv:0904.4259. What it means to “disprove a theorem” like Bell’s theorem is, however a subject for another comment section on a different blog.) But, and here is the interesting thing, this colleague then made a trip to China. And FriendFeed, apparently, is blocked by the great firewall of China, so he had to email us his comments to continue the conversation. Which got me thinking.
China is a country that has been, historically, a great power. It is, by all accounts, returning to that status with the a wave of lifting of its people out of poverty (numbers I’ve seen are from like over 60 percent below poverty a few decades ago to 10 percent recently, though it’s not clear to me that the poverty level (a few dollars per day) used is the really relevant number.) It has, even more interestingly, achieved an amazing increase in the production of people with a large amount of education. From under 10,000/year PhDs a decade ago to nearly 50,000/year recently, there has been a huge increase in PhDs in a very short span of time. In some minds, the rise of China is the dominant story of the coming decades. This is equally true in academic circles where the productivity of science in China has been rising rapidly.
But my colleague’s experience made me wonder a bit. Suppose that you take at face value the idea that online tools are going to change how we do science (through any of the numerous forms that such tools can now take.) If the Chinese government is banning tools that allow for collaboration (in our case, just a mere discussion) then, despite all they do, I wonder if this might cause a severe lack of bang for their Ph.D buck. Do we really believe that the kind of large scale data sharing or online collaborating, for example, that characterize Science 2.0 will be easy to carry out under the probing eye of the Chinese government? Of course, I’m as far from an expert in China and Science 2.0, so I can’t even begin to approach this question. But it did strike me that there are some fairly strong preconditions assumed by those pushing online tools for science that don’t seem to hold for numerous countries around the world, including China.
Or, in other words (executive summary), those of you doing Science 2.0 can now think about yourselves as modern freedom fighters. Hazzah!