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Alphabetical order in the blogroll July 11, 2008

Posted by dorigo in Blogroll, internet, personal.
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Just a short note to mention that I have decided to switch from a random to an alphabetically ordered list in the column of links to relevant other blogs -those I read and those I advise users of my site to give a peek at now and then (the two categories only partly intersect).

The reason is simple: despite the wide offer of blog feeds, collections, and other means by which one may get updated on what is being written in a collection of sites one wants to keep an eye on, I have never brought myself to using those tools. Maybe because I am fundamentally lazy -an old dog who wouldn’t learn a new trick- or maybe because I still enjoy going after information rather than having it showered on me on a regular basis.

Now, my blogroll column currently contains about fifty entries, and it grows sporadically -that is, whenever I have enough stamina to adjourn it. I have the habit of using that list to access the blogs, rather than my “blogs” folder in the preferites tab of my web browser (Mozilla), and a random list often causes me to scroll up and down in search for the link I need. That is stupid, and it has become a sufficient reason for abandoning my original idea of a “democratic” randomly compiled list which changes every time one accesses the main page of my blog.

So, I am sorry for Zerocold, or even worse for those links that get buried in the middle and never get a chance of a spot in the sunlight atop the list, but I am switching to an alphabetically ordered list today. There is an added bonus in the process: by making it easier for me to access the blogs I am linking, I make it easier for you too, in the hope that you, too, will use this blog as a default entry point for your visits to other sites. Or am I really the only one who still doesn’t uses blog feeds ?

UPDATE: Shoot! I just found out why I had been unable to change the order earlier on, when I gave it a try: as the WordPress FAQ explains, the theme I am using does not allow one to change the order of links!

Now I’m stuck to having to decide for a change of theme (which I really want to avoid), a frustrating retreat, or a bold advance into the new territory of a privately managed blog. If you know me, you’re likely to imagine what I will do.

Recent additions to the blogroll July 9, 2008

Posted by dorigo in Blogroll, internet, personal, physics.
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Today I have important business to attend so I only point you to three recent additions to my blogroll column, which call for your attention, if you so please.

  • The Gauge Connection, by Marco Frasca. Marco is a theoretical physicist and he works on perturbative QCD. He just started writing about physics, to a level suitable for undergraduates and above. I hope he will lower the bar a little, with the aim of discussing complicated theory constructions as one could do in a bar. That would be some achievement! In any case, his blog is worth visiting.
  • Dialogos of Eide, by Plato. This is a blog devoted to science in general, with attention to cosmology, quantum gravity, and experimental developments. Also worth visiting, although if you have a slow internet connection you might find yourself cursing at the heavy images.
  • Se me lo dicevi prima, by Marco Schwarz. This is a blog in italian but hey, not all visitors here are anglophones anyways. Marco writes about a bit of everything, and I like his style.

Fine tuning and numerical coincidences July 1, 2008

Posted by dorigo in Blogroll, cosmology, games, internet, physics, science.
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The issue of fine tuning is a headache for today’s theorists in particle physics. I reported here some time ago the brilliant and simple explanation of the problem with the Higgs boson mass given by Michelangelo Mangano. In a nutshell, the Higgs boson mass is expected to be light in the Standard Model, and yet it is very surprising that it be so, given that there are a dozen very large contributions to its value, each of which could make the Higgs hugely massive: but they altogether magically cancel. They are “fine-tuned” to nullify one another like gin and Martini around the olive in a perfectly crafted drink.

A similar coincidence -and actually an even more striking one- happens with dark energy in Cosmology. Dark energy has a density which is orders and orders of magnitude smaller than what one would expect from simple arguments, calling for an explanation which is still unavailable today. Of course, the fact that neither for the Higgs boson nor for dark energy there is as of today a solid experimental evidence is no deterrent: these entities are quite hard to part with, if we insist that we have understood at least in rough terms what exists in the Universe and what is the cause of electroweak symmetry breaking in particle physics. Yet, we should not forget that there might not be a problem after all.

I came across a brilliant discussion of fine tuning in this paper today by sheer chance -or rather, by that random process I entertain myself with every once in a while, called “checking the arXiV”. For me, that simply means looking at recent hep-ph and hep-ex papers, browsing through every third page, and getting caught by the title of some other article quoted in the bibliography, then iterating the process until I remind myself I have to run for some errand.

So, take the two numbers 987654321 and 123456789: could you imagine a more random choice for two 9-digit integers ? Well, what then, if I argued with you that it is by no means a random choice but an astute one, by showing that their ratio is 8.000000073, which deviates from a perfect integer only by nine parts in a billion!

Another more mundane and better known example is the 2000 US elections: the final ballots in Florida revealed that the Republican party got 2,913,321 votes, while the Democratic votes where only 2,913,144: a difference of sixty parts in a million.

Numerical “coincidences” such as the first one above have always had a tremendous impact on the standard crackpot: a person enamoured with a discipline but missing at least in part the institutional background required to be regarded as an authoritative source. A crackpot physicist, if shown a similarly odd coincidence (imagine if those numbers represented two apparently uncorrelated measurements of different physical quantities) would certainly start to build a theory around it with the means he has at his or her disposal. This would be enough for him or her to be tagged as a true crackpot. But there is nothing wrong with trying to understand a numerical coincidence! The only difference is that acknowledged scientists only get interested when those coincidences are really, really, really odd.

Yes, the feeling of being fooled by Nature (the bitch, not the magazine) is what lies underneath. You study electroweak theory, figure that the Higgs boson cannot be much heavier than 100 GeV, and find out that to be so there has to be a highly unlikely numerical coincidence in effect: this is enough for serious physicists to build new theories. And sometimes it works!

Johann Jakob BalmerThe guy in the picture on the right, Johann Jakob Balmer, got his name in all textbooks because of discovering the ratio (in the Latin sense) of the measured hydrogen emission lines. He was no crackpot, but in earnest all he did to become textbook famous was finding out that the wavelength of Hydrogen lines in the visible part of its emission spectrum could be obtained with a simple formula involving an integer number n -none other than the principal quantum number of the Hydrogen atoms.

So, is it a vacuous occupation to try and find out the underlying reason -the ratio- of the Koidé mass formula or other coincidences ? I think it only partly depends on the tools one uses; much more on the likelihood that these observed oddities are really random or not. And, since a meaningful cut-off in the probability is impossible to determine, we should not laugh at the less compelling attempts.

As far as the numerical coincidence I quoted above is concerned, you might have guessed it: it is no coincidence! Greg Landsberg explains in a footnote to the paper I quoted above that one could in fact demonstrate, with some skill in algebra, that

“It turns out that in the base-N numerical system the ratio of the number composed of digits N through 1 in the decreasing order to the number obtained from the same digits, placed in the increasing order, is equal to N-2 with the precision asymptotically approaching 10^{-N}. Playing with a hexadecimal calculator could easily reveal this via the observation that the ratio of FEDCBA987654321 to 123456789ABCDEF is equal to 14.000000000000000183, i.e. 14 with the precision of 1.3\times 10^{-17}.”

Aptly, he concludes the note as follows:

“Whether the 10^{-38} precision needed to fine-tune the SM [Standard Model] could be a result of a similarly hidden principle is yet to be found out.”

Ah, the beauty of Math! It is so reassuring to know the absolute truth on something… Alas, too bad for Godel’s incompleteness theorem. On the opposite side, whether one can demonstrate that the Florida elections were fixed, it remains to be shown.

The say of the week June 29, 2008

Posted by dorigo in Blogroll, internet, news, science.
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“We now have access to so much information that we can find support for any prejudice or opinion”

(David Suzuki)

Kudos to Ed Darrell for pointing out Suzuki’s activity in scientific divulgation and his project to our attention.

Sadly, no more gossip June 24, 2008

Posted by dorigo in Blogroll, games, physics, politics.
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These days my honest yet slightly anarchical style of blogging is becoming harder and harder to maintain. I am curiously receiving a synchronous input from the two opposing sides of the Atlantic Ocean: a true coincidence, because the origins of these inputs are totally uncorrelated. And yet the push goes in the same direction. Worse still: since the input is coming from authoritative sources, it would be idiotic to ignore it.

Good science works by encouraging an open exchange of information only in fairy tales. In reality, the human factor weighs in to modify that optimal picture. Man is ambitious, selfish, vain. And hundreds, or even thousands, such individuals gathered together in the same project make a sociological bomb that is only begging to be set off. Handling such a bomb is not an easy matter: therefore, I do understand the concerns of these giant collaborations.

Time and again I am told by readers that one of the things that make this blog interesting to read is the cut-away view I occasionally provide of the inner workings of the scientific collaborations I work in. Well, that feature of this site is bound to be slightly dampened. Posts such as this one, or even this one, might be considered a diffusion of internally exchanged information, and as such they would create trouble (the first one did, in fact).

I decided I will unwillingly oblige. Not so much because of the harm that my own scientific career might be exposed to if I were unreasonable: I am not ambitious -I have a good life, my job satisfies me fully, and I do not depend for my living on my ridiculous salary. Rather, I will oblige because I fully understand that keeping a blog with some audience requires a good dose of responsibility. One of the things that makes me proud is to have belonged and still belong to CDF, the longest-lasting and one of the most successful physics experiments ever; and nowadays, I am spending most of my time to earn the right to be proud of belonging to CMS too. I certainly want to help these experiments!

What this all boils down to is, I think, only that I will not post any more about the humorous sides of internal meetings -the rest has never made it to this blog anyway- and that I will compensate by writing a bit more about the physics. Not such a terrible deal after all. I will have to save my irony for other matters.

Fresh blogging from Neutrino 2008 May 26, 2008

Posted by dorigo in Blogroll, news, physics, science.
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I just found out that Kea (aka Marni Dee Sheppeard) is reporting in her blog from the Neutrino 2008 conference. I strongly advise to have a look at her notes – they have a much higher signal to noise ratio than my way too long posts from last week’s PPC08 talks.

And while you are there, remember to have a look at her lessons on Category Theory – just short than 200 lessons on it!

Another blog on PPC08 talks May 20, 2008

Posted by dorigo in astronomy, Blogroll, cosmology, news, physics, science.
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Just a note while I prepare my own summary of today’s talks: Mandeep Gill, a astrophysicist from Ohio State University, is also blogging on the talks we are listening at PPC08 this week. Please check his notes here….

A question to Al Gore – and his answer May 14, 2008

Posted by dorigo in Blogroll, internet, news, politics, science.
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I am very happy to post a link to my friend David’s blog, where he has a streaming video from an event in Rome, at the point where he poses a tough and interesting question to Al Gore on the accelerating debate on the Climate Crisis. Please have a look!

Streaming video on scientific divulgation May 13, 2008

Posted by dorigo in Blogroll, internet, italian blogs, news, personal, science.
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Just a link to a post by Gianandrea Giacoma on the site of the sci.bzaar.net workshop, an event about which I wrote here, here and here.

In the post, Gian uses very kind words to introduce a video on my thoughts on the need of horizontality in scientific blogs. I already posted a link to my video yesterday (beware, it is in Italian – I will try to find the time for an English version though, or at least provide a transcript in English), but the one on the sci.bzaar.net site does not need to be downloaded before playing – a huge bonus since you might get bored halfway through (oh well, damned if you do. It’s just 7 minutes).

A video on scientific blogging May 12, 2008

Posted by dorigo in Blogroll, internet, italian blogs, news, personal, physics, science.
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On Saturday, May 15th, a conference called “sci.bzaar.net” will take place in Milano. It will bring together a restricted group of researchers, psychologists, bloggers, designers, physicists, writers, philosophers, computer scientists and web experts, who will discuss scientific divulgation, production of knowledge, and open culture in the academic world.

I will not be there in person, but a video I produced for the event will be shown – and I will connect with skype or some other means to take questions. You can see the agenda of the workshop here.

In addition, I produced for the web site of the event another short video where I discuss the importance of horizontality in a blog aimed at scientific divulgation. Unfortunately, I only have a version in Italian so far (the event is aimed at an italian public). I will paste below a writeup as I have the time, but if you are interested you can see me in the 7-minutes video here (beware though, it is kind of heavy – 500 Mbytes!).