Physics

Scientists are often portrayed as serious yet quirky, but many hide a prankish interior.  Here's a butcher's dozen of famous pranks by -- or at-- scientists. The best lecture never heard.Mathematician G.H. Hardy was invited to give a keynote speech, and told the organizers he would present a proof of the famously unproven Riemann zeta hypothesis, but that they should keep that secret.  Upon arrival, his actual lecture was on a much more conventional topic.  The organizers asked him why he didn't present his revolutionary proof.  His reply?  He always says that's his…

This is my last post of my blog. I have decided to totally quit my blogging activities after the last incident. My participation in the scientific collaborations CDF and CMS has always been a problem, since whenever I discussed a topic here even mildly related to their business there was the potential of receiving heat from those colleagues of mine who believe that the scientific integrity of the experiment can be harmed by a blog post, or who imagine that grant reviewers be influenced by what is written by a collaborator in a private blog. If I look back at these six years of blogging, I…

On today's online version of the highest-diffusion newspaper in Italy, Il Corriere Della Sera (a bit too right-winged for me, but still an important source) stands a piece signed by none less than Carlo Rubbia, Physics Nobel prize in 1984 for the discovery of W and Z bosons. Despite his not so young age any more, Carlo is still extremely active in the field of high-energy physics, where he has moved his interest into neutrino physics. Just to explain what I mean with "active", I listened to his talk at NEUTEL11 just a couple of weeks ago, where he proposed a new neutrino experiment to be…

WARNING: This blog contains both ADULT language AND THERMODYNAMICS. If you are under 18 or do not like any laws that involve chaos, please leave by clicking on an ad to support this site. Time and space are joined at the hip. I mean this in a completely naked, having an amazing animal experience together kind of way. A review of the history of physics will support this scandalous claim.[click or skip, the video is a reading of contents contained herein] Sir Isaac Newton developed the mathematics of change, the calculus. In looking at the logical structure of the formalism, he concluded…

It has been a while since I last wrote about results from the DZERO collaboration, and I am happy to be given a chance to do so by my casual Monday morning browsing of the most recent Arxiv preprints. The fact that I am not a member of DZERO but I still know something about the experiment and its "environment" makes it fun for me to write about their results: despite knowing my way best when I take a walk through CDF or CMS results, I have to be quite careful there to avoid stepping on the toe of some collaborator (and sometimes it feels like their toes cover all the ground), plus I must…

"The observed exclusion limit is found from the point where the 95% quantile (dottedline) crosses the median value of the distribution of Q values for the QCD prediction(dashed line). This occurs at Lambda = 9.5 TeV. The expected limit is Lambda = 5.7 TeV. [...]As a cross-check, a Bayesian analysis of F(mjj) has been performed, [...]. This analysis sets a 95% credibility level of Lambda > 6.7 TeV. The expected limit from this Bayesian analysis is 5.7 TeV, comparable to the CLs+b expected limit. While the observed limit from CLs+b analysis is significantly higher than the Bayesian results…

This might become the title of a series of posts, much like my "say of the week" series. In fact, the Large Hadron Collider is back in operation since earlier this month, and the instantaneous luminosity at which it collides protons at a center-of-mass energy of 7 TeV is going to keep gradually increasing, as better orbit parameters are found, more protons are injected in the machine, more bunches are made to circulate, and beams are squeezed in the surroundings of the experimental halls. Still, it feels nice to report that the value of L = 2.4E32 cm^-2 s^-1 has been now achieved, a full 20%…

Lacking the papers to prove I am a theoretical physicist, I have built something working class: a lunchboxThe box contains Yoplait Yogurt, Del Monte 100 Calorie Mixed Fruit, and White Cheddar Cheese Smart Food Pop Corn (note: all product placements are unpaid). The apple included indicates I work on gravity. [The video is a reading of the content contained herein, so click or skip] Near the handle is the name I use to encompass this work, GEM, for Gravity and EM. The acronym has already been taken by gravitomagnetism. English is full of words with multiple meanings, so I hope people…

The CDF collaboration sent to the preprint arxiv a new paper a few days ago. In it, they report on a measurement of the mass difference of top and anti-top quarks. The result would not be worth discussing in detail, if it did not show a 2-sigma discrepancy which might be the first hint of a CPT violation. So let me discuss it here. "CPT" is an acronym for a symmetry of Nature that is generally believed to be absolutely conserved. Such properties of matter are best tested at a microscopic level, where things behave "simply" -if you understand quantum mechanics. Each of the letters in the…

My blogging output here is scarce this week, because I am spending my time at the NEUTEL 2011 conference in Venice. I am producing some posts summarizing the talks I hear at the conference, together with a few colleagues. Our blog there will be short-lived, but already collects about 1000 views a day, growing by the day. Here is a selection of recent posts you can find -I only list here those published today or yesterday: Art McDonald: Past and Present of Neutrino Oscillations Overview of Neutrino Phenomenology Jeffrey Wilkes; SuperKamiokande G. Fiorentini: GeoNeutrinos L. Corwin:…