A Quantum Diaries Survivor

Muons are very special particles. They are charged particles that obey the same physical laws and interaction phenomenology of electrons, but their 207 times heavier mass (105 MeV, versus the half MeV of electrons) makes them behave in an entirely different fashion.

For one thing, muons are not stable. As they weigh more than electrons, they may transform the excess weight into energy, undergoing a disintegration (muon decay) which produces an electron and two neutrinos. And since everything that is not prohibited is compulsory in the subnuclear world, this process happens with a half time of 2 microseconds.

Have you ever behaved like an a**hole? Or did you ever have the impulse to do so? Did you ever use your position, your status, your authority to please yourself by crushing some ego? Please answer this in good faith to yourself - nobody is looking behind your shoulders. Take a breath. I know, it's hard to admit it. But we all have.

It is, after all, part of human nature. Humans are ready to make huge sacrifices to acquire a status or a position from which they can harass other human beings. Perhaps we have the unspoken urge to take revenge of the times when we were at the receiving end of such harassment. Or maybe we just tasted the sweet sensation it gives to use your power against somebody who can't fight back.

What is a twistor, and why should we care? Well, I may not be the most qualified blogger out here to give you an answer, but I will try to at least give you an idea. Before I do, though, maybe first of all I should say why I am discussing here a rather obscure mathematical concept, in this typically experimental-physics-oriented blog.

Twistor theory is a mathematical construction that dates back to the sixties, and is probably mostly known for some of its uses within string theory. Funnily enough, it has now been brought to the fore by Peter Woit, a mathematical physicist from Columbia University who became internationally renowned when he published his 2006 book "Not Even Wrong".

As of late we have been scratching the barrel of "straightforward" measurements of the properties of the Higgs boson, the particle discovered in 2012 by the Large Hadron Collider ATLAS and CMS experiments. But the one property determined in the measurement published yesterday by the CMS experiment was one that many of us were very interested to check.

If a particle is an elementary body, how many individual, distinct properties can it really have? For the word "elementary" means that it is intrinsically simple! But things are not so clear-cut in the subnuclear world. An elementary particle, while devoid of inner structure and dimensions, still has a number of measurable attributes. For the Higgs boson we may size up:

- mass (of course!)

Experimental physics is about investigating the world in a quantitative manner, by exploiting our technology to carefully map the wealth of phenomena that make planets turn around stars, atoms stick together, and hearts to beat. All of that can be understood by creating models of the underlying physics processes. These models need to be fed with input parameters which we must measure.

On July 6th, at 7PM CET (1PM in NY, 10AM in California) I will be chatting online with David Orban on his show Searching For The Question Live (#sftql) about the present and future of particle physics, artificial intelligence and its applications to research, science communication, and the whereabouts. I hope you will be joining us, it should be fun!

For those of you who do not know who David Orban is:

I did not think I would need to explain here things that should be obvious to any sentient being, but the recent activity I detect on Facebook and other sites, and the misinformation spread by some science popularization sources and bloggers around the conclusions reached last week by the European Strategy Update for Particle Physics (EUSUPP), a 2-year-long process that saw the participation of hundreds of scientists and the heavy involvement of some of our leading thinkers, forced me to change my mind.

Fundamental science works by alternating phases of interpretation and refutation. When interpreting the result of experiments, physicists spend their time sweating shirt after shirt in the attempt of formulating economical and coherent explanations of observed phenomena. If the process converges, they formulate a theory which works well, whereby they celebrate for a little while. Then a second phase starts, when hypotheses are formulated on how to refute the shiny new model, finding effects and observatons that do not fit in the formulated framework. And so on.

The text below is the sixth and last part of what could have become "Chapter 13" of the book "Anomaly! Collider Physics and the Quest for New Phenomena at Fermilab", which I published in 2016.

The text below is the fifth part of what could have become "Chapter 13" of the book "Anomaly! Collider Physics and the Quest for New Phenomena at Fermilab", which I published in 2016. For part 1 see here; for part 2 see here; for part 3 see here; for part 4 see here.

No superjets in Run 2

The text below is the fourth part of what could have become "Chapter 13" of the book "Anomaly! Collider Physics and the Quest for New Phenomena at Fermilab", which I published in 2016. For part 1 see here; for part 2 see here; for part 3 see here.

The offer of Ph.D. positions in Physics at the University of Padova has opened just a few days ago, and I wish to advertise it here, giving some background on the matter for those of you who are interested in the call or know somebody who could be.

The Ph.D. in Italy

In Italy, Ph. D.s last three years (the duration can be extended but this is not recommended). Courses start with the first academic semester, so the calls typically open in the spring, and admission tests are run in the summer. The system is not too different from that of other countries, but there are peculiarities of which you might want to be aware.