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On Rating Universities

In a world where we live hostages of advertisement, where our email addresses and phone numbers...

Goodbye Peter Higgs, And Thanks For The Boson

Peter Higgs passed away yesterday, at the age of 94. The scottish physicist, a winner of the 2013...

Significance Of Counting Experiments With Background Uncertainty

In the course of Statistics for Data Analysis I give every spring to PhD students in Physics I...

The Analogy: A Powerful Instrument For Physics Outreach

About a month ago I was contacted by a colleague who invited me to write a piece on the topic of...

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Tommaso DorigoRSS Feed of this column.

Tommaso Dorigo is an experimental particle physicist, who works for the INFN at the University of Padova, and collaborates with the CMS and the SWGO experiments. He is the president of the Read More »

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Higgs boson hunters often catch themselves dreaming of the boson having a mass high enough to give rise to the spectacular decay into two Z bosons, and then four charged leptons in the final state. At a hadron collider -let's talk of the LHC to be specific- such a signature is the only one providing events which, once properly selected, are more likely signal than background.

The situation of observing an event display being able to tell for sure what it represents, among the infinite possibilities and the intrinsic indetermination of quantum processes, is reassuring and gives a physicist a feeling of power. God did not play dice this time: those two are 100% Z bosons, and their combined mass is exactly the one of the Higgs.
I read with interest and some amusement (on the mouse joke) the piece written here by Sascha Vongehr. I find his arguments wrong and decided to answer him in the comments thread of his post, but my answer got a bit too long and I did not want to hijack a nice discussion that was developing there; plus I found out that what I was writing could be suitable for this blog in its own right. So below I explain what I criticize about his arguments.
"We consider the scattering of charged W bosons [...] the sum of all diagrams still diverges as s/Mw^2. Heavy leptons cannot help us, so the only solution is to introduce a scalar particle which cancels these residual divergences [...] Here, h is just the Higgs particle. If we had not previously introduced it to generate the heavy boson masses, we would have been forced to invent it now to guarantee renormalizability [...] Higgs particles have so far eluded experimental searches [...] one might speculate that they do not exist as elementary fields, adn the higgs "particle" we have introduced actually corresponds to a more complex object [...]"

F. Halzen and A.D. Martin, "Quarks and Leptons", J.Wiley&sons 1984, p.344.
Fabrizio Tamburini (left) is an old friend - I have known him since 1976, when we both used to attend the gatherings of the newborn Associazione Astrofili Veneziani, at the Lido of Venice. The love for astronomy had brought us together, but we took different paths in our scientific activities. Fabrizio remained maybe more faithful to his old love for the universe, and is now a well-known and respected astrophysicist, who studies original ideas in the physics of photon propagation and more. I repeatedly invited him to write about his research here, but so far he has not accepted, mainly for lack of time... But I am sure he will soon.
The Draconids (also called Giacobinids) are a meteor shower associated to comet Giacobini-Zinner (see below for a 100-year-old picture of the comet). While most years this shower passes unnoticed to all but few professionals and experts amateurs, yielding only very few meteors in the nights between October 6th and 10th, every once in a while the Draconids do put up a real show, producing hundreds, or even thousands of meteor streaks per hour in clear skies.
One of the issues that emerged in the discussion of whether researchers should be bloggers is the fact that it is always dangerous to wear multiple "hats", i.e. carrying multiple responsibilities which may sometimes come in conflict with one another.

Wearing two hats

Of course this is a very common and old problem. I am indebted to Jim S.M., who sent me a few excerpts from Churchill's autobiography, which are very relevant to the issue besides being quite amusing: