Physics

The American Chemical Society's Spring 2010 National Meeting and Exposition includes numerous research findings in the field of cold fusion, also known as Low Energy Nuclear Reactions (LENR). Here is the video of the live press conference that gives a broad introduction to the people involved and their views on this controversial part of science.



Blocking Temperature
1. Superparamagnetism
Quasicrystals

Quasicrystals

Mar 19 2010 | 0 comment(s)

Quasicrysstals

A brand new result in Higgs boson physics has been presented by my old-time CDF colleague Wei-Ming Yao at the Moriond QCD conference two days ago. It is the combination of CDF and DZERO limits on the Higgs boson, and it constitutes a significant advancement in our knowledge of the standard model.

The result is simple to state in a single sentence, although it will take me several pages to explain it acceptably. The Higgs boson is excluded at 95% confidence level in the 130-210 GeV mass range, if there are four generations of matter fields.
In 1950 Immanuel Velikovsky published his bestselling Worlds in Collision, where he proposed that Venus was once a satellite of Jupiter that went AWOL and caused catastrophes on Earth as it flew past. Nobody believes this now, and few believed it then either, but you can see how it would work using a solar system simulation designed by PheT.
How to explain resonance to a non-scientist? A few years back I heard a guest speaker on BBC Radio 4 trying to explain the resonance effects of pulsed microwave radiation on the brain in contrast to the thermal effects of the carrier frequency: sadly he failed miserably. What is it about resonance that makes it so hard to explain?

I have taught it to A-level students and to undergraduate engineers. Electrical engineers, in particular, need to be thoroughly familiar with the phenomenon and yet, I could see that its significance eluded them. There are few, if any, good visible examples in real life. The Tacoma Narrows Bridge is one famous example, where strong winds set the bridge oscillating. Eventually it hit its resonant frequency and collapsed.
I was delighted to receive news this afternoon of three new interesting results produced by the DZERO collaboration in the analysis of Quantum Chromodynamics (QCD) processes.

QCD, the theory of strong interactions between quarks and gluons, is the "boring" part of the physics of high-energy hadron-hadron collisions. It used to be more more exciting twenty years ago, when the theoretical calculations were not as refined as they are now, and there was still a lot to understand in the physics of strong interactions between quarks and gluons. But nowadays, things are much more clear.
The CDF collaboration, which runs one of the two proton-antiproton collider experiments at the Fermi National Accelerator Laboratory since the early eighties, has published hundreds of scienticif papers in the course of its 25 years of operation. I believe the number has abundantly surpassed the half-thousand mark, but I am unaware of its exact entity.
On March 8th, international women day, the CMS experiment at CERN will be run almost entirely by women. 32 of the 34 shifts needed to run our experiment will be covered by women scientists of our Collaboration - which counts 588 women overall.

I think this is great news and a very good idea. 588 women scientists are quite an impressive force! And believe me, most of them really do kick ass!!
Yesterday somebody asked me here if I could explain how does a muon really decide when and how to decay. I tried to answer this question succintly in the thread, and later realized that my answer, although not perfectly correct in the physics, was actually not devoid of some didactic power. So I decided to recycle it and make it the subject of an independent post.

Before I come to the discussion of how, exactly, does a muon choose when and how to decay, however, let me make a few points about this fascinating particle, by comparing its phenomenology to that of the electron.