Physics

Great news for the CMS experiment - and for Italy, and for my institution, Padova, where I coordinate accelerator-based physics research for INFN. Professor Roberto Carlin, a longtime member of the CMS experiment, where he has taken many important roles in the construction and operations of the experiment, and recently was deputy spokesperson, has now been elected spokesperson. This consolidates a "rule" which sees Italian physicists at the lead of the experiment every other term, after Tonelli (2010-12) and Camporesi (2014-16).  More in general, Italy is confirmed once more to be one of…

Great news for the CMS experiment - and for Italy, and for my institution, Padova, where I coordinate accelerator-based physics research for INFN. Professor Roberto Carlin, a longtime member of the CMS experiment, where he has taken many important roles in the construction and operations of the experiment, and recently was deputy spokesperson, has now been elected spokesperson. This consolidates a "rule" which sees Italian physicists at the lead of the experiment every other term, after Tonelli (2010-12) and Camporesi (2014-16).  More in general, Italy is confirmed once more to be one of…

Some shameless self-promotion is in order today, as my review titled "Hadron Collider Searches for Diboson Resonances", meant for publication on the prestigious journal "Progress in Particle and Nuclear Physics", has been made available on the Cornell Arxiv.My review covers quite extensively the topic, as it is not constrained in length as other reviews usually are. At 76 pages, and with 500 references, it aims to be the main reference on this type of physics for the next five years or so - at least, this is the stipulation with PPNP. Whether I managed to make it such, it is something to be…

The recently released paper noting that dwarf galaxy's orbits do not obey the simplest models of dark matter is not news to any physicist who pays attention to cosmology.  In short, the simplest models of dark matter, the DM in CDM, may need to be tweaked but hopefully not by too much.  So the rest of the media and everyone else can relax.  That's not to say the work isn't very important.   I am a advocate of alternative models and try to formulate such models just to see if I can.  I also strongly believe that alternative models are needed just in case standard…

The field of particle physics is populated with believers and skeptics. The believers will try to convince you that new physics is about to be discovered, or that is anyway at close reach. The skeptics will on the other hand look at the mass of confirmations of the current theory -the Standard Model- and claim that any speculation about the existence of discoverable new phenomena has no basis.Believers are fun to argue with, and often I manage to bring them to put their money where their mouth is, by offering to take bets on the fact that the LHC will discover new particles or forces in the…

A search just posted on the Cornell arXiv by the ATLAS Collaboration caught my eye today, as it involves a signature which I have been interested on for quite a while. This is the final state of proton-proton collisions that includes an energetic photon and a recoiling dijet system, when the dijet system may be the result of the decay of a W or Z boson - or of a heavier partner of the Z, called Z'. The setting We are talking about research being carried out at the CERN LHC, the Large Hadron Collider. The machine has been producing data since 2015 in what is called "Run 2", and the ATLAS…

The Plenitude Principle says “all possible exists”. According to hype, the Plenitude Principle is the result of quantum mechanics and particular Many Worlds Interpretations (MWI) of quantum physics. However, the Plenitude Principle is self-evident and likely many thousand years old. Pierre Fermat suggested considering ‘parallel worlds’ to Blaise Pascal in 1654 [Devlin 2008]. Such scientific Many Worlds/Minds (MW/M) descriptions facilitated the development of probability theory and were essential in the development of statistical mechanics in the nineteenth century, for example in the work of…

Peer review is the backbone of high quality scientific publications. Although the idea that only articles that are approved by a set of anonymous nitpickers can ever see the light of publication on "serious" journals is old and perfectible, there is currently no valid alternative to identify verified, rigorous scientific work, and to filter out unsubstantiated claims, and methodologically unsound results - the scientific analogue of "fake news".In practice, the method works as follows. A scientific journal receives an offer to publish an article by a scientist or team of scientists, or…

Scared by the void of Christmas vacations? Unable to put just a few more feet between your mouth and the candy tray? Suffocating in the trivialities of the chit-chat with relatives? I have a solution for you. How about trying to solve a few simple high-energy physics quizzes?  I offer three questions below, and you are welcome to think any or all of them over today and tomorrow. In two days I will give my answer, explain the underlying physics a bit, and comment your own answers, if you have been capable of typing them despite your skyrocketing glycemic index.1. An experiment…

In the previous post I discussed the generalities of "diboson production" at the LHC. Dibosons are pairs of elementary bosons - the photon (carrier of electromagnetic interactions), the W and Z bosons (carriers of the weak interaction, respectively charged and neutral), the gluon (carrier of the strong interaction, and coming in 8 undistinguishable varieties), and the Higgs particle. Looking for proton-proton collisions of high energy that give rise to resonant pairs of elementary bosons gives access to a host of new physics scenarios. In all cases (but one, which I maybe will touch on…