Physics

Exotic baryons, what are they ? But first of all, what is a baryon ? Well, it depends whom you ask the question to. In the context of the static quark model, a baryon is a particle composed of a triplet of quarks, as opposed to a meson, which is a particle composed of a quark-antiquark pair. But the quark model is fifty years old, and nowadays we know better: baryons and mesons do not just contain a triplet or a duo of quarks; they are in fact a soup of quarks and gluons. What is still true is that their intrinsic properties are distinguished by the _valence_ quarks they contain. Valence…

Meteorites - stones that fall on Earth from space - are quite rare, but not so much as to make their possession impossible. In fact I know a few collectors of these strange bits of matter; and I find the very strange-looking stones quite fascinating. I myself own a small piece of tectite fallen somewhere in South Africa a few decades ago; but it is just an odd bit in a larger collection of minerals and crystals that formed on Earth (yes, I find those even more fascinating; but that's just me).One of the biggest collectors of meteorites in Italy is also one of the true experts on the matter,…

The 13 TeV data from LHC collisions taken this summer is quickly going through analysis programs and being used for new physics results, and everybody is wondering whether there are surprises in store... Of course that will require some more time to be ascertained.For the time being, I can offer a couple of very inspiring pictures. CMS recorded a spectacular event featuring two extremely high-energy jets in the first 40 inverse picobarns of data that was collected and reconstructed by the experiment with all detector component properly working. The two jets have a combined invariant mass of 5…

There have been many news stories saying that the EM Drive will solve almost all problems in interplanetary travel, permit low cost flying cars and who knows what else. Other stories say that it is flat out impossible and we shouldn't spend a single publicly funded research dollar on it. But I haven't seen a single article with the rather boring suggestion that perhaps in this case the research community has got it exactly right. That it's not a perpetual motion machine, doesn't deserve to be dismissed out of hand. But it's far too soon to justify huge research programs into it, even if it is…

Are you a post-lauream student in Physics, interested in pursuing a career in particle physics, and maybe with interest in advanced machine learning applications, with an eye to a great job after your PhD ? Then this posting is for you.The AMVA4NewPhysics network is now offering its first 36-month scholarships, to perform research with the Large Hadron Collider experiments ATLAS and CMS, searching for new physics and studying the properties of the newly-discovered Higgs boson. The salary is in the 47000-53000 euro/year range, depending on family situation of the candidates. We strongly…

Well, as some of you may have heard, the restart of the LHC has not been as smooth as we had hoped. In a machine as complex as this the chance that something gets in the way of a well-followed schedule is quite significant. So there have been slight delays, but the important thing is that the data at 13 TeV centre-of-mass energy are coming, and the first results are being extracted from them. 13 TeV is a whole 62.5% more than the 8 TeV of the 2012 collisions, and getting there was a real challenge: first of all, safety systems had to be installed in all the magnets to ensure that no accident…

I apologize for my lack of posting in the past few days. I will resume it very soon... So as a means of apology I thought I would explain what I have been up to this week.- I have been fully absorbed on Monday and Tuesday with the signing of the Grant Agreement of the AMVA4NewPhysics ITN network. The thing is, while there is a rather relaxed deadline for this set by the European Community (12 August), my network fell in a complicated mix of University closures, vacations of the persons responsible for signing the papers, and bureaucracy of administrative and legal offices in the various nodes…

Normal 0 MicrosoftInternetExplorer4   Generalization of Newton’s inertia principle in flavor phenomenology    Generalization of Newton’s inertia principle in euclidean 3-space is related to the flavor degree of freedom of the quantum reality. When there are several mass copies, single particle mass must be replaced by the quantum concept of mass matrix; it introduced new additional dimensional quantities besides direction angles of the particle momentum vector – mixing angles and mass ratios of the copies.    Inertia law states that with no forces (no external…

    If you like star trek or similar science fiction, you have probably heard of the term, "space-time continuum". Well it is a real thing, as is time, and yes the definition of time still works for all of our day to day scheduling of events and activities.      When things start moving near the speed of light or are in a strong gravitational field, time might seem to go awry. We all have a good appreciation for length, width and height. As fundamental as these three dimensions are to our understanding of the world around us, modern science tells…

The reported observation of a resonant state of a J/psi meson and a proton in the decay of the Lambda_b baryon by the LHCb collaboration, broadcast by CERN today, is a very intriguing new piece of the puzzle of hadron spectroscopy - a topic on which many brilliant minds have spent their life in the course of the last half century. Now, I am honoured to know, and have hosted in this blog in the past (where he wrote about doubly heavy baryons, one of his favourite topics) Professor Marek Karliner, who has been investigating composite hadrons for a long time. So I was really happy…