Archive for April, 2008

Slow poisons

Posted in G 0 with tags , , , , , on April 30, 2008 by Roberto Gravitazero

Albert Hoffmann, the discoverer of LSD, passed away yesterday at the age of 102 years. He was also the first to synthesize psylocibin, the active substance of several hallucinogen mushrooms. He experimented the effects of the drugs he invented upon himself, and defended during all his life the potentially beneficial effects of LSD assumed in a controlled way.

Reading this piece of news today, I was reminded of the following anecdote about Voltaire, which my grandfather used to tell me when I was a kid:

Voltaire, who drank copious amounts of coffee throughout his life, was once told by somebody that the beverage was a slow poison. “I fully believe it. And it must be indeed very slow,” he replied, “for I have been drinking it for sixty-five years and I am not dead yet”.

Voltaire indeed died at 84, a ripe old age for his times.

I’ve heard my grandfather recounting this little story in a few occasions, while he was making coffee. However, I don’t remember him especially as a coffee enthusiast. But, even in his late years, he never refrained from drinking an healthy quantity of wine during meals, although I’ve never seen him even slightly drunk.

He died the day of his hundred and first anniversary.

Slow poisons, yeah.

April 25

Posted in G 1 with tags , , , on April 25, 2008 by Roberto Gravitazero

After a consultation with our musical experts, we have chosen our sound-track for today. Sorry for the Macarena fans. Enjoy.

Dance to the New Music

Posted in Uncategorized with tags , , , , , on April 22, 2008 by Roberto Gravitazero

ANSA reported that Marco Tedde (Forza Italia), mayor of the city of Alghero in Sardinia, had forbidden the town band to play the well known song “Bella Ciao”, the anthem of the Italian partisans, during the celebrations of next April 25th, anniversary of the liberation of Italy from Nazi occupation. He took this decision, he explained, in order not to foster conflict.

We now expect him to issue a list of recommended songs, maybe slightly less suitable for the occasion but also less controversial. Such list could for instance include “Jingle Bells”, “Mickey Mouse March” and “La Macarena”.

He was right !

Posted in G 0 with tags , , , , on April 17, 2008 by Roberto Gravitazero

Intermittently, during the last days, I found myself wondering how was ever possible that such a large fraction of the Italian population ended up voting for the Joker and his allies. And every time, the reason behind this had escaped me. But, as often happens, the solution was right there, in plain view.

So, I finally grasped it today, while I was reading my own blog (a quite stupid activity indeed, that in general I carefully avoid).

Bossi was rigth! The ballots were really treacherous and confusing. Millions of Italians have been cheated!

No one in his right mind could ever vote for him, actually. It’s much more reasonable to assume that many poor, uninformed, well-meaning voters had been confused by all these mixed-up symbols…

So, since my attachment to democratic values is not less than the one of Lega Nord followers and Bossi himself, I’m now trying to remember where I’ve stored my old gun. And, since my shooting skills are a bit rusted, I think I’ll begin my defense of democratic values precisely with the Lega Nord leader. A slowly moving target is what I need for a good start.

I’ll keep smaller, faster targets for later.

Paint it Black

Posted in G2 with tags on April 14, 2008 by Roberto Gravitazero

SB

From Bioetica. But Chiara Lalli posted it on Saturday. Either she can read the future, or she’s a pessimist. Or she was just being realistic, and I’m too optimist. I fear the last one is the right answer.

Doubts

Posted in G 0 with tags , , , on April 13, 2008 by Roberto Gravitazero

While Italy is hanging on the (possibly ominous) outcome of the ongoing political elections, in Spain Zapatero had formed his new government. Nine women, and only eight men. Good news. A woman, Carme Chacon, had been nominated minister of defense. She is now just over seven months pregnant. Very good news. It is indeed a strong, positive message to appoint a young woman to a role generally considered to be an exclusive playground of old alpha males.

Only, there is something that nags me. It seems a somewhat non-kosher thing to involve a pregnant woman in military matters.

Maybe, this is not such a great news after all. I don’t know.

Let’s say, I’d rather receive a much better news. Something like this – I can imagine Zapatero presenting the government:

“…and finally, Ms. Chacon had been appointed as Minister of Foreign Affairs. No one will cover the role of Minister of Defense. Not for lack of candidates, for we had indeed many worthy possible candidates .Of any gender, age, religion and sexual preference. Only, we decided, the ministry itself is going to be abolished.”

But then, one cannot really expect that much.

Not even from Zapatero, I guess.

Yes, We Could.

Posted in G 1 with tags , , , , on April 11, 2008 by Roberto Gravitazero

With less than two days left to go, this is my last post on statistical analysis and predictions on the Italian elections. In the previous posts I had a look at the possible outcome of the race for the Senate, based on available polls data. I will try today to have a reflection on two issues:

1) Is it conceivable that, contrary to all published polls, PD would eventually end up with more votes that PdL, thus securing the majority in the lower chamber?

2) In such a case, what would be the result, in term of seats, at the Senate?

After the polls blackout (15 days before the election date), results from putative reserved polls can be found on the net, in various flavors and disguises (horse races being a rather popular choice, but not the only one). Since I have no way to check how real and reliable these are, I would ignore them and base myself on available data alone, plus some elementary statistics. Only in the end I will add some more “political” consideration.

Starting with question one, the obvious starting point is a comparison with the 2006 elections, in which the polls predictions disagreed strongly with the final result. I show in the plot below the results of the pre-election polls and of the exit polls in 2006 , compared with the 2008 polls. I report as well the final results of 2006, and a hypothetical break-even point for 2008 (PD equals PdL).

In 2006, all polls gave a substantial margin to the Center-left coalition (average in the last month before the blackout 4.8 %), except from 3 polls from 2 institutes, all commissioned by Berlusconi. Such margin was essentially the same even in the exit polls, but was dramatically contradicted by the final results.

At a first look, a PD close victory in 2008 would be an even bigger surprise than the “almost draw” of 2006. The absolute discrepancy of the final data from the last month polls average (7.7 %) would be higher than the one of 2006 (4.9 %), and even more so in relative terms (since PdL and PD percentages are lower than what Center-left and Center-right obtained in the last elections). However, for several reasons, a PD victory cannot be completely ruled out. First, the data looks more “dynamic” in 2008. Besides that, the spread of the data in 2006 is noticeably less than the one of 2008 (especially if the 3 “anomalous polls” are not considered) – possibly due to the “disturbing” factor of the smaller parties now present in the race. If we consider only the last month before polls blackout in 2006, the final Center-Left and Center-Right results were -3 and +3.8 standard deviations away from the averages, respectively. This compares to the +/- 3.8 standard deviations needed to reach the break-even point in 2008. From a purely statistical point of view the two events would be essentially equivalent (i.e., equally unlikely).

The cause of the 2006 discrepancy had been thoroughly discussed. A systematic bias in the polls looks more likely than a drift of electoral preferences in the last two weeks (as confirmed also by the exit polls result). The bias could then arise from non-representative sampling by the polling institutes, reticent answers by part of the interviewed population, or a biased voting distribution in the undecided who finally participated to the elections. The repetition of such a discrepancy in 2008 (and its magnitude and direction) depends on all the above as yet undecided issues. To add another variable, I ignore if the polling institutes had since 2006 put in place corrective strategies, and which ones.

The only possible conclusion is therefore that, if a similar phenomenon happens again, there would be ample space for a PD victory at the lower chamber (but also, potentially, for a large defeat).

In order to try and answer to question two – Senate outcome if PD overtakes PdL – I have done a simple exercise. I have taken the March 2008 polls average and used my model (derived by the one from Sandro Brusco/noiseFromAmeriKa) to study the dependence of PdL and PD seats in the Senate as a function of the PdL-PD distance (keeping the PD+PdL sum constant). I have then repeated the simulation two more times, first adding, then subtracting 1% to both SA and UDC.

In the following plot I show the results, together with the simulations done using the actual March polls (scattered dots). It is interesting to note that the two +/- 1% bands (thinner lines) describe well the variability of the polls.

At a first glance, the conclusion is that a small advantage of PD over PdL would in general not be enough to obtain the majority in the Senate, or even to obtain just more seats than PdL. PD would need a lead of 5% or more to be likely to get the majority. Which looks like a long shot indeed.

However, the simulation I did follows a strict uniform national swing hypothesis. A re-distribution of the votes between regions different from 2006 (as by the way showed in the few published regional polls) could dramatically alter the results, in a way that is difficult to predict. The number of seats are indeed more sensitive to the distribution of votes among the regions than to their global number. I was surprised to find, for instance, that by shifting around less than 100000 votes, it was easy to “give” the senate majority to PD (158 seats) with only a 1% lead with respect to PdL. Thus, even for the Senate, a small possibility for a PD majority do exist.

I have so far talked about statistical possibilities. One must add a “political” dimension in order to make an educated guess on the outcome. For instance, most commentators (and a few polls) maintain that most of the undecided who will finally vote will favor PD rather than PdL (opposite from 2006). Also, the 2008 polls show a Center-left to Center-right ratio more unbalanced towards the latter than ever before. Since in paste elections the movements between the two block were minimal, this could imply a poll bias in favor of PdL.

For these reasons I would expect a reduced PdL-PD gap in the end. If I had to bet, I would place my money on a PdL victory with a 2-4% margin at the lower chamber, and an essential draw in Senate seats. But nothing is excluded, and Veltroni does well to keep up the pressure.

Yes we can sounds too optimistic to me, since the bar is indeed set very high. But I would’t object to a Yes we could.

Open Doors

Posted in G 0 with tags , , , , on April 8, 2008 by Roberto Gravitazero

Last Saturday and Sunday CERN had opened its doors, giving to the general public a chance to visit the laboratory, and especially the underground areas, where the access will be limited after the LHC startup.

Therefore, like many other people in CERN, I have devoted the last week-end to the Open Day 2008.

In fact on Saturday I was guiding people around the CLIC test facility, whose commissioning is an essential part of my job. On Sunday my contribution was less direct (if not less tiring), since I was taking care
of my two-year old son all day, while my wife was acting as a guide to the CMS experiment underground installation, where she works, and giving a talk about CERN in a nearby village.

Today I was sent an e-mail, like the other 1500 or so volunteers, with the official numbers for the Open Day participation:

On Saturday, 5 April: 23,000 visitors to the various sites, of which 11,000 to the tunnel and underground caverns.

On Sunday, 6 April: 53,000 visitors to the various sites, including 20,000 to the underground areas.

Indeed, many visitors had to patiently wait for their turn, sometimes for a few hours. And some had to be sent to different, less busy, locations. In spite of that apparently most of them went away deeply satisfied from the visit.

What can I say? I think I should feel privileged to be among the few – with the possible exception of employees of the Louvre museum – who work in a place where other people are willing to suffer hours of queue just to have a quick look around.

P.S.: And nobody asked me anything about black holes, either.

Gun(boat) Democracy

Posted in G 0 with tags , , , on April 7, 2008 by Roberto Gravitazero

Yesterday Umberto Bossi, leader of the Lega Nord party, declared in Verbania that the ballots being prepared for the coming Italian elections are “unclear” and “prone to generate errors”. He then stated:

“Se necessario, per fermare i romani che hanno stampato queste schede elettorali che sono una vera porcata, e non permettono di votare in semplicità e chiarezza, potremmo anche imbracciare i fucili.”

Concluding then:

“Volevo dire che noi alla democrazia ci teniamo e che democraticamente reagiremo a ogni tentativo di impedire la chiarezza e la regolarità in cabina elettorale.”

Which in English would be (my translation – could well sound a bit less illiterate than the original):

“If needed, in order to stop people from Rome who printed these ballots which are a real junk, and don’t allow to vote clearly and in a simple way, we could as well make use of rifles.”

And:

“I wanted to say that we are attached to democracy and we will democratically react to every attempt to prevent clarity and lawfulness in the electoral booth.”

I must say I’m relieved to hear that Lega Nord members are so attached to democratic values, and would thus limit themselves to accepted democratic procedures like the use of guns and rifles. It seems therefore that their use of nuclear weapons in order to prevent, e.g., illegal electoral propaganda, can be excluded.

I conclude adding that apparently, some Lega Nord enthusiasts, having found several flaws in the pencils being prepared for the elections, are proceeding to a hasty substitution of the same (see photo). However, it seems that a Lega Nord representative had declared that the methods employed are not likely to result in any unwanted casualty.

Down the Drain? (Featuring also an Unexpected Sexy Ending)

Posted in G 0 with tags , , , , , on April 2, 2008 by Roberto Gravitazero

drain2.jpg

I have to confess you one thing. I am lazy. Really lazy. Everybody who knows me well enough can confirm. And, being lazy, I tend to postpone things. So, when I saw this article on the New York Times, I thought I should write a post on it. Only, since at the time I was busy, I postponed. Then, when I actually had the time, I delayed it again. Then I discovered that half the blogs in my blogroll had already posted about it. And, on top of that, in reality, I had already talked about the matter in this post, before the New York Times article was published. So, I decided to give it up. Even if, indeed, working at CERN and being the only blogger not writing about it was quite a shame. But, what the hell, why waste time on it, when there wasn’t much I could possibly add to dozens of other posts? (Did I tell you that I’m lazy, by chance?)

However, today I come across an aspect of the matter that I thought deserved a small effort. But you would have to wait until the end of the post to know it. Before that, I want just give you the useful pieces of information I wanted to publish in the first place.

No, the earth will not go down the drain of a black hole generated in the LHC. There are lots of reasons why it won’t happen. But the more basic one, and the easier to understand, is that particle collisions like the ones that will be obtained in the LHC (if we’ll make it work, which is another matter altogether…) are happening all the time around us, and had happened since quite some time already. Cosmic rays (in fact particles) with energies reaching values much higher than the LHC could ever dream to obtain, collide every day with protons and nuclei both on earth and other planets. The only reason to build LHC instead of studying these same events is this: Cosmic ray collisions have the somewhat irritating habit of happening all over the place, and not nicely pile up in a detector just to please a bunch of impatient physicists. Dirty little scoundrels that they are – the particles, I mean. Anyway, since the earth, the moon and other planets are still in their place since quite some time, we are safe (well, from this danger at least). Black holes, if ever they are created in particle collisions, either evaporate fast and nicely as this guy Hawking predicted, or interact so weakly as to pose no real threat.

I would add another useful bit of info as well. A short biography of Dr. Wagner, apparently written by himself as a host of this radio show:

Walter Wagner graduated UC Berkeley with a Minor in Physics, and a Major in Biology. Later, he discovered a novel particle in a balloon-borne cosmic ray detector, initially identified as a magnetic monopole. Though its identity remains uncertain, it is definitely not within the standard repertoire of known particles. After a three-year break from science to attend law school, Dr. Wagner resumed work in Physics and Biology at the US Veterans Administration Medical Center in San Francisco, working in Nuclear Medicine and Health Physics. He then embarked on teaching Science and Mathematics, from grade school to college. Dr. Wagner developed a botanical garden in Hawaii, and continues involvement with several professional associations, including Health Physics Society and Society of Nuclear Medicine.

So, a biologist, a physicist and a lawyer. I indeed have no problem to believe the world could be saved by a physicist. Or even, stretching a bit the imagination, by a biologist. But nobody can make me believe that the world could possibly be saved by a lawyer.

What about the peculiar aspect I mentioned at the beginning – you didn’t forget about it, right?

Well, the fact is that the good old New York Times, thanks to an unfortunate misspelling, had involuntarily given birth to a new category of porn, as documented for instance here (nice WordPress theme, by the way).

But if black holes could in theory be generated in LHC, I’m not quite sure I want to know what can be the outcome of a Large Hardon Collider.

PS: The image on top was linked in a comment on one of the blogs in my blogroll, actually in conjunction with the LHC black hole business. What is actually depicted there, where I did find it and which ones among the blogs I link have dealt with this matter is left as an exercise to the interested reader.

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