A Quantum Diaries Survivor

You don’t need to be an oceanographer like Curtis Ebbesmeyer to love the idea - you just need to have been a child some time ago. Twentynine-thousand plastic ducks, the kind of toy you always find in the bathtub of small children, were dispersed in the pacific ocean in 1992 when a storm wrecked three containers of a cargo ship off the coast of China. They have since traveled the seven seas, some of them landing in Australia, others on the coast of Chile, and more than 10 thousand still around the globe, traveling about a mile a day in a long cold trip through the Bering straits, then frozen in pack ice, and finally thawing out in the warmer Atlantic waters - as Ebbesmeyer had predicted.

The retired oceanographer has spent his time following the ducks and other plastic toys in their 15-years journey. And valuable information has been obtained from the observation of the wanderings of these little plastic creatures. Indeed, they appear to be worth ready money… 

The Daily Mail, from which I stole the picture above, has the full story.

Mercilessly speared by deadlines converging on my flesh and bones, I am only able to point to the commendable work of others to entertain you today. Below is a short list of interesting science-related posts I found in blogs I read or stumbled upon.

• Resonaances has a very good post about the new bounds on dark matter cross section obtained by the XENON-10 collaboration. A factor of 6 improvement over previous results, and a limit that start cutting into the flesh of CMSSM allowed regions.
• Babe in the Universe tells us, in her usual witty style, of a giant storm on Mars. Her blog is always up to date with astronomy news.
• String conferences are all the rage this summer. At Strings 2007 Witten has given a talk and produced a paper worth a look, if you like the genre. Information and discussion at the Arcadian Functor and at  Peter Woit’s blog.
• Alexey Petrov explains that the PVLAS result on magnetically induced vacuum dichroism -and the related possible axion interpretation- has been revised, and no signal is actually there: it was a detector effect.
• To close the list with one item that doesn’t belong, Jennifer Ouellette has little physics in her post on roller coasters, but I enjoyed reading the history of these things and related trivia.

WordPress recently updated its stats bookkeeping, and now I get to see the access statistics to the permanent pages linked in the tabs above. In particular, the old and slightly odd page “About me” -a mix of a curriculum vitae and a post about my hobbies- is being visited frequently enough to make me decide it is due time to revamp the whole thing.

I am thus putting together a list of meaningful posts with text or pictures to paint some quick picture of myself. It is up there, labeled “who am I?”. Still working on it - I need to fish out the useful stuff from a 1000-post-long list. And then there are those in the old quantum diaries blog… Oh well. It will take some time.

Thanks to the web site of Il Corriere della Sera, one of the leading italian newspapers, I got to see this brilliant video, aired in Australia to instill in youngsters the concept that driving fast as a means of self-assertion can actually backfire.

The message passed by the video is clear: You drive fast ? You probably have a small penis, and you dump on the gas pedal all your frustration.

I cannot express strongly enough my admiration for the matter-of-factness and bold free hand of the authors of the campaign. Like the ad against smoking by Yul Brinner dying of lung cancer, this one is destined to save hundreds of lives. Well done folks!

By the way: strangely enough, I do drive fast, but… Oh well. It is a well-known rule in statistics that you can’t compute a meaningful correlation coefficient with less than five penises.

CDF has recently used the production rate of top quarks to increase by 20% the precision of one of its top mass measurements. A nice new technique and a brand new result, of which I will say more at the end of this post: I wish to explain here a few basic facts about particle production in hadron collisions first.

When you collide a proton with an antiproton with enough energy, what is actually happening is that the two particles “see” each other as drops of liquid within which lie tiny hard spheres. The drops sometimes just bounce against each other without losing their integrity: it is what we call an elastic scattering;  (more…)

Here are a few links from blogs I visit, which I found interesting today.

• Sabine, at Backreaction, has a nice post on the physics of the highest energy cosmic rays.
• This site allows you to rate movie-like a site by its contents. I thus found out my blog made it to the PG category (see sticker on the right), due to the presence of “hell” (twice) and “death” (once) in my page (I do not know how deep the bot spied the contents here though). Credits for spotting this to Jennifer Ouellette.
• Clifford Johnson tells us about the Name that particle contest. Quite nice. I think I am submitting my own contribution.
• Through David Orban’s blog I got to know We feel fine, which is an artwork as well as an “incredible display of the power of the web to transform the way we think about humanity”, to quote David. Remarkable!

During weekends the rate of spam comments to this blog (and my guess is to any other) is far higher than during weekdays. This, combined with the fact that I may be unable to seep the list of blocked comments on Sunday, and the lower rate of meaningful comments this blog receives during weekends (like many others), brings the signal-to-noise ratio in the spam list almost undistinguishable from zero.

Due to the above, I have decided that, starting NOW, I will discard all spam messages I receive during weekends, without trying to salvage the occasional meaningful comment blocked by the Akismet filter.

If you are about to post a comment here and it’s weekend time, please be careful: avoid links, trivialities, and if at all possible back it up. If you do not see it appear quickly in the page, send it to me by e-mail at dorigo (at) pd (dot) infn (dot) it.

Thanks!

Very sorry to all of you physics geeks, but here comes yet another post about chess. They come in waves, as my love for the game knows moments of high fever alternating dormant periods.

The title of this post refers to the fact that chess positions, unlike most other human activities, allow us to get to the bare, beautiful truth, and the process can at times give an intense satisfaction. Chess is an art, and it is a science, both in its very peculiar way.

A  comment by Derek Slater to my post on the nice queen sacrifice 27.Qc7+!! forced me to analyze the position a while longer. Here is the starting point, after Derek’s proposal of 26. … Nxe5 (instead than the move played in the game, 26….Na7):

Now, says Derek, it seems like white can still play 27.Qc7+ Rxc7 28.Rxc7+ Kd6 29.dxe5+ Bxe5, (more…)