Thursday, October 31, 2013

Tuesday, October 22, 2013

Al via, domani 23 ottobre, il Festival della Scienza di Genova

Festival della Scienza Bellezza

Genova, 23 ottobre_3 novembre 2013

Si intitola “Quello che non so” lo spettacolo conferenza dedicato ai grandi misteri della fisica contemporanea ideato dall’Infn per la serata inaugurale del Festival della Scienza di Genova, mercoledì 23 ottobre. Si tratta di un evento unico che propone un format sperimentale pensato per il grande pubblico in cui si alternano talk show scientifico e performance artistiche. Interverranno i protagonisti della scoperta del bosone di Higgs, valsa il Nobel per la Fisica 2013 a Peter Higgs e Francois Englert, Guido Tonelli (spokesperson emerito esperimento Cms) e Fabiola Gianotti – in collegamento dal Cern (spokesperson emerito esperimento Atlas). Accanto a loro Caterina Biscari (ricercatrice Infn e direttore del laboratorio Cells Alba di Barcellona) e Antonio Zoccoli (Giunta esecutiva Infn). Nello spettacolo "Quello che non so" la narrazione scientifica sarà accompagnata dalle suggestioni del mago delle bolle di sapone Marco Zoppi e dai quadri di sabbia animati dalla sand artist Gabriella Compagnone. A condurre la serata sarà Marco Castellazzi (Rai 3 Geoscienza). Lo spettacolo è una nuova versione, aggiornata nei contenuti e nell’impianto artistico, dell’evento "Lo Show dell’Universo" realizzato dall’Infn a Città della Scienza di Napoli nel settembre 2012.

Monday, October 14, 2013

Birth, death, resurgence (and death again) of an idea

One might think that only few great scientists are blessed with those “eureka” moments when, all in a sudden, a great discovery is standing just before their gleaming eyes, so clear and obvious that it cannot be wrong. In my experience, this expectation is very far from reality.

I think that many, if not all, people working on intellectual activities can experience the same feverish excitement that hit Archimedes in its tub. And they actually do so on a regular basis!

The thing is, the relevance of any scientific achievement is very personal and it is proportional to the effort one has put to reach it. No matter whether such achievement would be universally important or not, it will anyway be so for its discoverer. Only great scientists have the privilege to feel such excitement for great discoveries, but most scientists would anyway feel exactly the same emotion after solving much humbler problems, simply because they finally overcome some long-standing intellectual challenge.

There is another big difference between great discoveries and those made by the “scientist of the street”. The former can last forever whereas the latter hardly survive overnight. Furthermore, because Science is sadistic, the more relevant the discovery appeared at the beginning, the shorter the time it will survive. Therefore, although any scientist can feel the birth of her/his own ideas – whatever small its intrinsic impact might be – it is also true that most of us have also to face the frustration of seeing that idea dying as quickly as it was born. I like to believe the same happens to great scientists as well.

Sometimes this process repeats itself continuously, each new idea being accompanied by more mistrustful joy and its possible death being followed by less sorrow. I consider myself lucky in this respect, because I can easily get over-excited after having some new idea (if not in front of a computer, this usually happens on the way back walking from work, so my humble suggestion is to leave your car in the garage) but I don't feel particularly sad when such idea turns out to be completely wrong, as it happens most of the times.

Actually, I think this experience is common to the majority of my colleagues and it is truly fortunate that the excitement following some potential new idea largely overcomes the almost-unavoidable letdown for its failure. After all, I believe, such feeling is the real thrust of the scientific process, the reward any scientist is intimately working for.

The one above is my own contribution to the outreach project "Birth of Ideas", created by Ana Sousa and Vitor Cardoso. If you have an interesting anecdote to tell, please read the instructions and submit your contribution!

Saturday, October 12, 2013

The 9 kinds of physics seminar

The “Typical” starts innocently enough: there are a few slides introducing the topic, and the speaker will talk clearly and generally about a field of physics you’re not really familiar with.  Somewhere around the 15 minute mark, though, the wheels will come off the bus.  Without you realizing it, the speaker will have crossed an invisible threshold and you will lose the thread entirely.  Your understanding by the end of the talk will rarely ever recover past 10%.
Read the rest on Many Worlds Theory

Wednesday, October 2, 2013

The Unbearable Baldness of Black Holes

One of the most awe-inspiring properties of black holes is their absolute simplicity, or as John Wheeler famously put it, "black holes have no hair". As their progenitor collapses, its memory is forever lost, and all that remains is a quiescient, bald black hole. In a new article in Physical Review Letters, a team of scientists (that only by chance includes me...) has shown that black holes can nevertheless "grow hair" in the presence of matter, connecting them to the rest of the host galaxy.

Black holes are almost xeroxed copies of one another, differing at most in mass and rotation. These objects are described by a solution discovered by Roy Kerr in 1963. Remarkably, Kerr black holes are ubiquitous in almost any other theory of gravity, to the extend that the "Kerr hypothesis" is the current paradigm in astrophysics. 

First time I saw this picture was in one of Stephen Hawking's popular-science books, probably 'Brief History of Time'. It is supposed to describe the 'baldness' that this post refers too, am I the only one finding it a bit pathetic? :)
We have shown that in simple and attractive extensions of Einstein's theory (known as scalar-tensor gravity) black holes may not be described by the Kerr metric, as was previously thought. The crucial ingredient is the matter surrounding astrophysical black holes, typically in the form of accretion disks. The presence of matter triggers an instability that forces the bald Kerr black hole to develop a new charge -- a "scalar hair" -- connecting it to the matter around it and possibly to the entire galaxy. 

This hair growth is accompanied by a peculiar emission of gravitational waves, potentially by upcoming laser interferometers, which may test the Kerr hypothesis and probe the very foundations of gravity.

Read what real outreach journalists wrote on this on:
Huffington Post
Portuguese newspaper Público