Physics

CMS is one of the two huge detectors built to study the high-energy collisions of protons produced by the Large Hadron Collider at CERN. As all previous collider detectors, CMS is a redundant multi-purpose collection of dozens sub-detector components, which use different physics mechanisms to detect everything that comes out of the collision point, from protons to muons to photons, neutrinos (using the energy imbalance in the calorimeters), neutral hadrons. A transverse cut-away view of the CMS detector is shown below, with the different signals that arise from the interaction of different…

Today I spent the better part of the afternoon in the company of 150 high-school students at the Liceo Fermi in Padova, giving a seminar on particle physics in the context of a project called "Masterclasses" which has been active since 2005 and is a big success. The project aims at students in the last years of their high school and attempts to involve them in the experiments undergoing at the CERN laboratories. Sets of lectures on particle physics and cosmology at the schools are followed by a "hands-on" session at the Physics Department, where students are taught and then tested in…

Every two years physicists and astrophysicists who work in the area of neutrino physics get together in the wonderful setting of Palazzo Franchetti, a historical palace on the Canal Grande in Venice, Italy, to discuss the latest results of experiments and theoretical ideas, and to plan for the future. The conference series has now reached its fifteenth edition. It will take place from March 11th to March 15th, that is in a month from now. It will be the first time without Massimilla Baldo Ceolin, who passed away in November 2011; the last edition in 2011 was also organized without Milla's…

Everyday we rely on information transmitted through satellites. Some are close, orbiting just above the earth’s atmosphere, while others circle at a distance of 30 or 50 times further into space. They are placed into a given orbit based on need: what does the satellite need to see, and how does it need to travel with respect to the surface? These requirements must also come to terms with the essential physics for stable orbit, where the centripetal force equals the gravitational force. In short, satellites closer to the earth must travel faster, circle the earth with greater frequency, and…

I quickly wrote a short paper, "Broken Symmetries, Massless Particles and Gauge Fields", which described how gauge theories may evade the Goldstone theorem, and submitted it to Physics Letters. It was received on 27 July and published 15 September. Before writing up the work on what is now known the Higgs model I spent a few days searching the literature to see whether it had been done before. I thought that Schwinger, in particular, might well have done something of the kind years earlier and I might have overlooked it. When I had satisfied myself that he hadn't, I wrote a second short paper…

The puzzle of dark energy, the dark cloud of 21st centry physics, is possibly solved. A postdoctorate, Wan-Jiung Hu, solves this puzzle in his book "Theories of Everything by Logic". Wan-Jiung Hu is a MD(National Taiwan University) and PhD(Johns Hopkins University). Currently, he is a postdoctorate in Taiwan. The author is highly interested in physics research as a formal member of German Society of Physic. The author is also an associate member of American Geophysical Union. In the book, the author propose that dark energy is actually light pressure. Photon emitted from galaxy will travel…

1:1 In the beginning Newton declared space and time. 1:2 And space was without form, and void; and darkness was upon the face of the deep. 1:3 And Newton said, Let there be force: and there was force. 1:4 And Newton saw the force, that it was good: and Newton divided force from straight motion. 1:5 And Newton called force change of momentum, and straight motion he called momentum conservation. And the evening and the morning were the first day. 1:6 And Newton said, Let there be a force in the midst of matter, and let it divide matter from energy. 1:7 And Newton divided matter which were under…

Quite some time ago I discussed here the tentative Y(4140) resonance  claimed by the CDF collaboration in their Run II data. This was a peak which was found in B-decay data containing a J/Psi signal, a phi meson, and an additional kaon track, and it resulted from the  study of the mass difference of the J/Psi + phi signal and the J/Psi alone. Confused ? You have all rights to be. I will explain everything in good order, but be sure that the matter was puzzling not only for laymen but also for insiders: because the find was mysterious, not predicted by existing models, and…

The history of the cosmos. In quaternionic physics one equation plays a major role. It is a mixture of a differential equation, a continuity equation and a coupling equation.Φ = ∇ ψ = m φHere Φ, ψ and φ are continuous quaternionic distributions or more specially they are quaternionic probability amplitude distributions. ψ and φ are normalized. m acts as a coupling factor. ∇ is the quaternionic nabla. The real part of it takes the differential with respect to the progression parameter. m follows fromm² = ∫ |Φ|² dV Here we focus onΦ = ∇ ψIt represents not only the definition of the…

The Omega_b particle is a quite peculiar baryon, made up by three heavy quarks: a b-quark, and two s-quarks. Because of this composition, where only down-type quarks appear, the phenomenology of the decay of this particle is really spectacular: both the b-quark and the strange quarks take quite some time to decay, and as they take shifts to do it the Omega_b first transmutes into a Omega (a particle made up by three s-quarks!), then into a Lambda, and finally into a proton. Each of these decays generates a reconstructable decay point, so one can reconstruct the whole chain perfectly. A…