Physics

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My most visible contribution to particle physics after my death might well one sad day turn out to be the sketching of W and Z boson identification diagrams I made in 1999 for a talk I was to attend at Moriond QCD. I must have been on a bright day when I set out to make those graphs, because everywhere I turn I see somebody using them -without paying any recognition to me of course. I noticed the trend two years ago, and I get reminded of it periodically. Recognition is not an issue, of course. I totally subscribe to the internet rule "grab what you like, use it as you please". References to…
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Today I wish to offer you the preview of a poster which I am going to show on September 1st in Kobe, Japan, at a session of the 29th edition of the Physics in Collisions conference. The CMS experiment, I remind you, is one of the four detectors which will start to measure the debris of proton-proton collisions at the Large Hadron Collider, in Geneva, when the latter starts operations a dozen weeks from now. The other three experiments are called Atlas, Alice, and LHCb. Atlas is a direct competitor of CMS in its high-energy discovery program, while Alice focuses on the collisions of heavy ions…
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In thirty minutes I will jump on a flight to Frankfurt and from there to Kobe, Japan, where I am attending the twenty-ninth edition of the Physics in Collisions conference. No big talk in store for me this time; no Westminster central hall kind of thing, nor spotlights or interviews. I will just be presenting a poster. Well, two. For a 43-year-old staff physicist, presenting a poster is not a particularly prestigious task, although it is definitely not a shame either. Posters are normally prepared by students, who thereby get a chance to discuss their work at scientific conferences without…
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Today I wish to offer you the figure attached at the bottom of this article, which shows a combination of recent determinations of the rate at which the Tevatron proton-antiproton collisions produce single top quarks. The top quark is the heaviest member of a family of six. It has been discovered in 1995 by the CDF and Dzero experiments at the Tevatron, and since then it has been studied in great detail, since its phenomenology provides a lot of information on the theory of electroweak interactions. That is actually kind of strange, since quarks are most of all subject to the strong force,…
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To start the process, I'm copying a post from my original blog.  I might post some of those entries here. Especially the ones which have  had a decent response. The purpose of joining this community is to have a blog dedicated to popular scientific writing. The biggest advantage of this venture is that it will teach me how to communicate vague andintuitive physical ideas in a clear scientific language. This article assumes a preliminary knowledge of axiomatic thermodynamics.   But do proceed nevertheless! ------------------ We’ll see if this way of looking at entropy makes it…
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Today, although fully submerged by an anomalous wave of errands which had been patiently waiting for my return at work, I heroically managed to dig out of the ArXiv a paper worth a close look. The study, titled "Likelihood Functions for Supersymmetric Observables in Frequentist Analyses of the CMSSM and NUHM1" and authored by renowned supersymmetry experts like John Ellis and Sven Heinemeyer, and experimentalists like my CMS colleagues Albert De Roeck and Henning Flacher, had me thinking that Supersymmetry does have an answer for everything, apparently. That, at least, is what one gets from…
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The figure shown below represents the best measurement of the top quark mass ever obtained by a single experiment, and it is a determination with a less than 1% total uncertainty. It has been approved last week by the CDF experiment at Fermilab. The CDF experiments collects proton-antiproton collisions delivered by the Tevatron collider, which imparts the projectiles with 1 TeV of energy each, for a center-of-mass energy of 2 TeV. This is still the highest energy ever achieved by a collider, although the record is going to be soon stripped off Fermilab by the Large Hadron Collider, which is…
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"We would dig a shaft near 'ground zero' about 10 feet in diameter and about 150 feet deep. We would put a tank, 10 feet in diameter and 75 feet long on end at the bottom of the shaft. We would then suspend our detector from the top of the tank, along with its recording apparatus, and back-fill the shaft above the tank.As the time for the explosion approached, we would start vacuum pumps and evacuate the tank as highly as possible. Then, when the countdown reached 'zero', we would break the suspension with a small explosive, allowing the detector to fall freely in the vacuum. For about 2…
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Google “E=mc2 is wrong” and you get 1,060 hits. Google “E=mc2 is correct” and you get a mere 138 hits. There you have it. It took us a more than a century, but finally this crazy inconsistent theory of relativity got outvoted. Common sense cries victory! Fortunately, science does not work that way. Science is no democracy, and we do not render a theory invalid by popular vote. Einstein's theory of relativity has stood the test of time and its correctness is beyond any doubt. But... there is an issue with what is arguably the most famous equation in the history of natural sciences. So what is…
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The World Conference on Science Journalism held in London 2009 has its own web site, of course. Today they were so kind to let me know they had published there the recordings of all sessions, among which was the one where I gave my speech. The session title was "Blogs, Big Physics, and Breaking News", it featured Matin Durrani as chair, and Matthew Chalmers, myself, and James Gillies as speakers. The abstract ran as follows: How are blogs changing the way science news develops and is reported?The commissioning of the Large Hadron Collider at CERN will offer atelling case study over the next…