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A couple of media bites for italians and russians November 18, 2008

Posted by dorigo in Blogroll, internet, italian blogs, language, news, personal, physics, science.
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Just for the record, allow me to point out here a couple of media bites on the anomalous muon signal published by CDF. They would be easy to miss otherwise, unless you speak russian or italian; in the latter case, even if you do.

The first is an article just appeared online and in print on the russian edition of Newsweek. It profusely quotes me as well as Peter Woit, and it focusses on the aftermath of the CDF publication rather than on the analysis itself. I obtained a rather fallacious italian translation with google, but you may try your luck with your own mother tongue.

The second is a radio interview I will be giving this Saturday (Nov. 22) on Radio Città Fujiko (at 10.30-11.30AM italian time, on the FM at 103.1MHz), in a science popularization program called “Caccia al Fotone” (photon hunt). I do not know the details of what we will discuss, although I know it will loosely center on the tentative new physics signal unearthed by the CDF collaboration a fortnight ago. If you are interested, you can SMS your questions to the radio at 333-1809494, or via email at cacciafotone@radiocittafujiko.it . The program has its own blog too.

Comments

1. Fred - November 18, 2008

The Neue Zürcher Zeitung also had an article (in German) about the whole story (also more about blogging than physics) where this blog is mentioned.

2. bozox - November 18, 2008

The Newsweek article was, basically, a digest of your recent posts and comments to them – not the analysis-related ones, the scandal-related ones. From their perspective, the scandal is the story. *sad*

3. dorigo - November 18, 2008

Hi Bozox,

well, I would not take it so bitterly. We know how newspapers sell. They have to build a story around a piece of news. We buy newspapers, so we cannot really look down on them because of the occasional article which has an occasion to deal with science but prefers to deal with what’s around it. Newsweek is not bought for the science, so I do not find this reproachable. It would have been a bad article on Nature or on Physics World, but I find it perfectly appropriate for a general interest magazine.

Cheers,
T.

4. tomate - November 19, 2008

Radio Città Fujiko is a relatively small independent radio broadcasting from Bologna (they play much better music that average commercial radios), it is great that they are making a serious scientific program with interviews to expertes – I am not surprised at all, but it is a shame that major media do not feature similar projects (apart radio 3 which has its own well-done scientific program)

5. bozox - November 19, 2008

That, and they called you “irritable”.

6. Iphigenia - November 19, 2008

I agree that Strassler’s paper is odd. But frankly I don’t understand your assertion that “The collaboration is one, and it is more than a collection of individuals: it admits no subset. I know theorists are much more promiscuous in the way they associate and disperse in different author lists; but a collaboration is a collaboration, and once a member, you only get to decide whether to sign or not a paper, but the collaboration publishes, not you.”

Surely there must have been a spectrum of opinion among those who did not sign. Some were sceptical, but had no objection to the paper coming out; others, however, must have been totally opposed to the paper coming out at all. They were just over-ruled. Or are you saying that every member of CDF has veto power, ie that the paper can come out only if *every* member agrees? Surely not.

So Strassler’s emphasis of this point, while not very polite, has a clear reason: he is just saying that many members of CDF don’t believe the paper. And that is surely a relevant scientific point, because people in CDF are the best people to make that judgement.

If what I am saying is wrong, well, TD, you should realise that nearly everybody outside CDF interpreted things the way I have. Bottom line: if you don’t sign, you don’t believe it, and probably you want to dissociate yourself from it as much as you can.

7. dorigo - November 19, 2008

Bozox, that irritates me aplenty🙂
Cheers,
T.

8. dorigo - November 19, 2008

Hi Iphigenia,

apart from the fact that Strassler making the point that “many memers of CDF don’t believe the paper” is really odd, given that he spends nonetheless 20 pages to discuss alternative mechanisms that could have produced the signature, I think it is not a scientific point. It would be a scientific point if it were expressed publically in print, or even orally, by people with a name.

You know how science works: what counts is not internal notes or opinions muttered in the corridors, but publications, seminars, public presentations at conferences.

Science does not work by counting signatures, or spotting the absence of unnamed individuals in a list (they are the unknown ones, in fact, and not, as Strassler says, those who signed – you only get to know who they are by extrapolating the previous publications, with some uncertainty because names get off the author list constantly these days, and because of visitors, guests who sign occasionally, etc). There were no alternative seminars, no counter-papers, no nothing.

To be clear, I do know many distinguished CDF colleagues who were against the publication, and said so internally, for various reasons which I cannot unfortunately disclose, but have little to do with science. There indeed was a complex review process. But these colleagues do not represent CDF: CDF published the paper, they decided to stay out of it and, by not signing the paper, their opinion on it is now worth less than if they had. Unless they have blogs or they comment on them (Pasha Murat did in this site, for instance), or if they get interviewed by some zealous reporter looking for the controversy- you will not hear publically their opinion.

Anyway, I do not care much what opinion people have about the CDF result. I myself do think it is not new physics (I already guessed a 1% chance for NP – but that is a lot these days!). But I strongly believe it had to be published, because of its potential importance, despite the fact that it is clearly written that investigations are continuing: It had to be published since it has an obvious value, regardless of the correctness of this or that detail and the stress on this or that feature of the data: it is a warning about past measurements by CDF with the same datasets, and there are a few- the “scientific” reasons behind taking the name off the publication stand to zero. If Strassler wanted to make a point about the fact the analysis was unlikely to be correct, he had all means to do so, but he chose another way.

Cheers,
T.

9. dorigo - November 19, 2008

Hi tomate,

I also appreciated the contents of the program when I got to know it last week. We will see what comes out of this interview…

Cheers,
T.

10. Luboš Motl - November 19, 2008

The Russian text seems to be nothing else than a translation of some irrelevant comments at two blogs, and not exactly the best ones.

At least the author seems to be skeptical about your so-far unjustified accusations.

Your attack against Matt’s paper is bizarre, too. See the final 30% of

http://motls.blogspot.com/2008/11/parallel-universes-and-science-on-tv.html

to see details why.

11. dorigo - November 19, 2008

Hi Lubos,

I like your cautious “so-far unjustified”.

My “attack” is just some notes on the parts of his paper I did not like, and as I say in the post, there are many valuable pages in there. In any case, I make a few points, and on those I can be criticized. For instance, please explain the 75 pb estimate of the paper.

I will now check your blog…

Cheers,
T.

12. Luboš Motl - November 19, 2008

Dear Tommaso,

“so far unjustified” is about the worst status that such an accusation can have. It is very hard to rigorously prove that the accusations similar to yours are untrue. That’s why such accusations are so mean.

Also, I am flabbergasted by what you find so controversial about Matt’s computation of the 75 picobarns of ghost events. Let me give you a course on cross sections plus a crash course on multiplication because you clearly need it.

Matt explains very clearly, in the same paragraph, that by the ghost events, he means the 153,895 events in the “ghost sample”. He even gives his own explanation of the CDF procedure how the number 153,895 was obtained. But if you doubt that this is the number of the ghost events from the CDF paper, see pages 15 and 16 of the CDF paper where the number 153,895 of ghost events is mentioned.

Now, the mathematically remarkable part of my explanation that might be really tough for you. The cross section is obtained by the number of events divided by the integrated luminosity (claimed to be 2100/pb) by the CDF team.

Shockingly enough, 153,895 divided by 2100 is not 742 pb as you claim but 73.28, close to 75 pb as Matt claims. To verify my statement, you may purchase a special machine called the “calculator” from the grant paying incompetent Italian sourballs like you as “physicists”. Thank me for my deep calculations and recommendations.

You’re welcome.😉

Best wishes
Lubos

13. dorigo - November 19, 2008

LOL Lubos, you certainly would profit from a crash course in speed reading, because you obviously try, but fail.

What I say above is that Matt did compute the number as you quote, but failed to notice that the luminosity (not the xs) is not 2100/pb but 742/pb – inverse picobarns.

I even mention this mistake could have been avoided if he had picked up the phone… You would have avoided yours by reading my post a bit less fast.

Cheers,
T.

14. Luboš Motl - November 19, 2008

No, it is not. What you write is just complete rubbish.

When calculating the cross sections, one must obviously use the total integrated luminosity of all events that were observed – and that’s 2100/pb.

The 742/pb figure you refer to is just a way to measure a particular smaller subset of the (total) 2100/pb collisions – namely those collisions which are relevant for the correlated b-bar cross section measurements. These special 742/pb collisions are those that are acquired by the dimuon trigger.

But if some new (?) ghost events only occur among these dimuon events – in the 742/pb ensemble – it doesn’t mean that their cross section can be obtained by dividing the event number by the reduced luminosity, 742/pb. Because these dimuon events are more rare and occur in the subset only, they simply have a smaller cross section: it’s because 2100/pb is always in the denominator.

Your calculation has nothing to do with the subtle points of possible 25% errors discussed by Matt. The calculation you suggest would lead to three times higher cross section than the real one – something like 200 pb? You’re just completely deluded and if you still don’t understand why this point of yours was completely silly, you’re just hopeless.

15. dorigo - November 19, 2008

Lubos, please, stop it, you are wasting a reputation which cost you years of studies, besides making me pee in my pants from the laughter.

If I tell you the luminosity with which those 153000 events have been collected is 742/pb, you should pause before insisting in your mirror climbing, lest you end up injuring yourself badly. It is NOT 2100/pb, ok ? The fact you now really, really want it to be 2100/pb so that you do not look like a total fool here, does not unfortunately change the situation.

In any case, you should avoid this topic entirely. The cross section for “ghost events” with loose cuts is what it is, and it is not interesting. What is interesting is the cross section of the subset which is not attributable to QCD sources. But I gather you cannot understand this, so I will have a post on the topic to educate you.

Cheers,
T.

16. dorigo - November 19, 2008

By the way, for the occasional bystanders: the timing of the exchange above is interesting: comment 12 arrived at 5.55PM, and comment 14 at 6.48PM. I predict that the next comment by Lubos will take more than the 50 minutes interval between the previous ones. He is of course now desperately flipping the pages of the CDF paper, trying to figure out a way to get out of the dead end he’s slipped into :)))

T.

17. Luboš Motl - November 19, 2008

Dear Tommaso, you start to behave like a complete crackpot that makes Kea a supergenius in comparison. I can’t believe you are *so* dense.

The correct integrated luminosity in the denominator is always 2100/pb. This number, 2100/pb, is a coefficient waiting to be multiplied by cross sections – obtained for proton-antiproton collisions (imagine proton, antiprotons as initial states in a QFT calculation) and encoding proton and antiproton fluxes – to get the actual number of events of certain types.

The number 742/pb only tells us that in about 1/3 of the proton-antiproton collisions, a bottom-antibottom pair was believed to be created at the very beginning, as evidenced by the dimuon trigger. One could use this number, 742/pb, if it were true that all these events recorded with the dimuon trigger had the bottom-antibottom pair at the beginning of the event, and if all the cross sections were somewhat re-expressed as cross sections for bottom-antibottom collisions. Well, except that the bottom-antibottom are not really colliding here. They are just produced in 1/3 of the collisions.

But with some handwaving, one could perhaps re-express the cross sections as cross sections based on fluxes of bottom quarks and antiquarks, and the corresponding integrated luminosity would only be 742/pb because the fluxes would refer to fluxes of bottom quarks and antiquarks. The proton-antiproton events with silent dimuon triggers would be irrelevant/lost for all these bottom-physics purposes.

At any rate, this interpretation is unusable even with handwaving in the case of the “lepton jets” paper because the very point of the paper that you signed – although you have no idea what the paper actually says – is that in many of these collisions that excite the dimuon trigger, completely new physics and new particles (as opposed to bottom quarks) is created at the beginning of the collisions.

For example, Giromini et al. crazily postulate the pair-creation of particles h1,h2 and around 16 taus at the end of the cascades. At any rate, you can’t divide these things by bottom-quark fluxes or luminosities because there are no bottom quarks in the events over there. Instead, you must return to the previous general picture that survives – it’s a picture of proton-antiproton collisions at the Tevatron. The fluxes are fluxes of protons and antiprotons, not bottom quarks, and their integrated luminosity is 2100/pb.

If you can’t get this simple point even after this rudimentary presentation optimized for kindergartens, I recommend you harakiri.

18. dorigo - November 19, 2008

Lubos, I had warned you. You should have stopped this. Instead, you add more nonsense logs to an already hot fire, and you just earned a post about your ranting and raving, and about how ignorant about simple experimental concepts a theorist can be, especially if he is so arrogant to believe he does not need to think things over before speaking.

You will have to wait tomorrow for a detailed exposition of your ignorance, using quotes from this thread, in a separate post. But just a hint here, to send you to a night of tormented sleep: the CDF study is based on 742/pb. For some extra distributions, later in the paper 2100/pb are used, a dataset collected with one and a half year of additional running. The numbers we are discussing, 153000 events out of 700000, etc., and the wrong cross section estimate by Strassler, come from the 742/pb. Period.

Inventing bottom quark fluxes and sentences like “in about 1/3 of the proton-antiproton collisions, a bottom-antibottom pair was believed to be created at the very beginning” make me feel sorry for you. Why don’t you take a good advice, Lubos ? You misread the CDF publication. You misread my post. Not happy about that, you now made a complete fool of yourself. I really, honestly would not have wanted to get to this point, but I had indeed warned you. Now your ignorance will be exposed, for the fun of your many enemies and the disconcert of your few admirers.

Look out for a post tomorrow. Now, I am sure you’ll understand, my time is better spent with my family.

Cheers,
T.

19. Luboš Motl - November 19, 2008

Dear Tommaso,

unfortunately, in your case, you didn’t misread anything. The only problem with you is that you’re completely dumb. Let me inform you that a couple of particle physicists are reading your blog, they know that what you write is pure bullshit just like I do, and they will remember.

The 742/pb figure is only good for calculations where one assumes that the bottom-antibottom pair is at the beginning. For example, this reduced luminosity may be multiplied by the cross section

sigma (b goes to mu, b-bar goes to mu)

to obtain the number of events of this kind. Note that the subscript of the cross section above encodes the bottom-antibottom initial states. The whole point of the CDF paper is to claim that these ghost events don’t have any bottom-antibottom pair at the beginning. So the 150,000 “ghost” events shouldn’t really be clumped into the same group as the regular, bottom-based, non-displaced dimuon events, and it is absolutely unphysical nonsense to compute the ratios of these two groups’ event numbers.

I am looking forward to your suicidal idiotic posting in which you will emphasize that you have no idea what the term “luminosity” means. Right now, my bet is that you will indeed write this stupidity because the night won’t be enough for you to recover basic mental functions.

Best wishes
Lubos

20. An appetizer for the impatient lubologist « A Quantum Diaries Survivor - November 19, 2008

[…] Lubos Motl trackback I cannot resist directing the Lubophilites and the Lubophobes of you to the thread of the former post, where, out of the blue, Lubos starts an attempt at explaining why Strassler’s estimate of […]

21. Philipe - November 19, 2008

Dear Lubos,

Why do you waste time with Peter Woit? You wrote a long tirade over his BRST notes which are basically correct. Why don’t you shut up and let him post his correct notes on BRST. Perhaps a few people will find them rather useful. Don’t you have anything better to do? Research? A job? A social life? Why don’t you fill out an eHarmony profile and find a woman. Oh that’s right, you’re too sexist to marry a woman.

“Even more interesting is the second part because he effectively copies the section 3.2.1 of “Superstring Theory”, a classic 1987 book by Green, Schwarz, and Witten. What Woit says about the BRST issues is more or less correct – it’s what Green, Schwarz, and Witten have also written, after all.”

Yes, you should be familiar with this sort of thing. After all, you don’t write any papers, but you do talk about other people’s work these days. You see, what Woit did was write up a summary, and a useful summary. That’s what a lot of people do.

“Now, isn’t it ironic for a vitriolic, Al-Qaeda-style critic of string theory to choose a section of a string theory textbook as a source of explanations of a topic that he views important?”

Yes, that’s called using a reference. In this case, the reference is called “Superstring Theory”. Just because he opposes string theory, doesn’t mean he’s not allowed to use something from a string theory book.

“But none of his anonymous readers – or the journalistic garbage that has promoted the jerk in the media two years ago – cares because all of them are equipped with hypocrisy of an unprecedented degree.”

Go see a therapist.

You may not agree with my recommendation that you go see a therapist, or my assessment that you have nothing better to do. That’s fair. But surely you agree with me about my points regarding Woit’s BRST notes and your response to them.

If you delete this post, and suppress the views of people who disagree with you, then why do you even have a blog? Blogs come with comments, and not every commenter will agree with the views of the blog’s author.

Have a good day.

22. Philipe - November 19, 2008

Dear Tommaso,

You may delete my previous comment if you wish. I’m so sorry. I shouldn’t have said those things.

23. piscator - November 19, 2008

Dear Lubos,

I suggest you have a look at chapter 10 of Ellis-Stirling-Webber. There you will find the bb_bar x-section for pp_bar collisions, and the fraction of the total x-section bb_bar production gives.

At 1.8Tev, they give 20 microbarns x-section for bb production, comprising 0.03% of total x-section.

piscator

24. Dan Riley - November 20, 2008

Lubos,

When CDF says they used data corresponding to an integrated luminosity of 742/pb (for one part of the analysis), they really do mean integrated luminosity, not some “reduced” luminosity. If you are still confused on this point, you might check your understanding of footnote 5 on p. 29.

-dan

25. bozox - November 20, 2008

Thread hijack: now I know what does “chicken cacciatore” (sp?), the dish, mean. Hunter-style, right?

26. Andrea Giammanco - November 20, 2008

I think Lubos is confused by the fact that the most recent CDF and D0 papers were based on 2100/pb. Please notice that CDF and D0 have currently ~3000/pb on tape (or even more, things go fast) but new data have to be completely processed and understood, before being used in an analysis.
Probably this CDF paper is still based on ~700/pb because they started the approval process when only this statistics was “ready for analysis”, and the approval process (understandably) took much longer than usual.
The fact that they mix ~700/pb with ~2100/pb in the same paper can give a hint of the phylogenesis of the different sections: the last checks that they added could profit from the most recently acquired data.
Probably it was considered irrelevant to rerun the entire analysis on the full statistics since the effect they observe is definitely not a rare one, so it’s preferable to use well-understood data rather than more data.

27. Lubos the experimentalist « A Quantum Diaries Survivor - November 20, 2008

[…] whole thread is available here, but let me nit-pick a few pearls for the lazier of you. “The 742/pb figure you refer to is […]

28. dorigo - November 20, 2008

Andrea, the CDF analysis is based on 742/pb for 28 pages, and on 2100/pb for the rest of the paper. The part which deals with the smaller luminosity does that because those first data were taken by a unprescaled trigger. Later data are useful for kinematics but less straightforward to use for cross section estimates and rate comparisons, because of the instantaneous luminosity-dependent prescale.

Cheers,
T.

29. Andrea Giammanco - November 20, 2008

Now everything is crystal clear, thanks!

30. A chat with Arkani-Hamed at CERN « A Quantum Diaries Survivor - December 9, 2008

[…] third was the trap into which poor Lubos Motl fell head first, when I asked him to justify a wrong cross section […]


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