We are just a few hours away from the announcement of the winners of the 2021 Nobel Prize in Physics. While waiting, I think back to last year – the tumultuous 2020 – when exactly in these same days Reinhard Genzel, Andrea Ghez, and Roger Penrose were awarded the Nobel Prize in Physics. The prize was awarded to them for their observational (Genzel, Ghez) and theoretical (Penrose) studies of black holes. These works are not particularly recent, Fonte:Nobel and sufficiently well established to have already entered university textbooks by the time when I was a student – when Instagram did not exist yet (in the distant 2012).
To be precise – as every researcher should be – the term “black holes” is used only in the motivations for the award to Penrose. Ghez and Genzel were the first to discover the super-massive black hole at the center of our galaxy, but despite the almost unanimous consensus of the scientific community, the Royal Swedish Academy of Sciences preferred to remain vague and mention a “compact super-massive object”. Caution – as every researcher should know again – is a must-have when there is no direct evidence: the fact that the surrounding stars orbit around the Milky Way core at such a speed could be due to the gravitational attraction of a huge alien garbage dump – which would contain about 1034 tons of junk compacted into a volume that would fit inside the orbit of the Earth.
As an astrophysicist I think (and hope) I have some familiarity with the subject, so I didn’t dwell into it too long. Instead, I decided to read the biographies of the three scientists hoping to find some interesting anecdotes, since the combination of science & gossip has the same effect on me as macaroni and cheese (respectively). I’ve also tried on several occasions to convince the staff of this publication to include a “Heart & Brain Mail” column, but apparently it’s not in line with editorial policy – too bad. If you are reading this, maybe you could send an email to Monnalisa to support the idea.
To no small disappointment, Wikipedia offered no mischievous insights (I should have read Der Spiegel instead). I then turned my attention to another aspect: the journeys the three Nobel Laureates have taken along their careers. Let’s summarize them for each one, in order of seniority – because if it was not clear, earlier in the article I have listed them in alphabetical order.
Studied in London, PhD at Cambridge in 1958 where he also got a research grant (so far he’s a pure mathematician). He then worked at Princeton (New Jersey, USA), Syracuse University (New York) and a year at the University of Texas in what is probably the least Texan city in the whole state (Austin). He came back to England in 1964 and started to work on cosmology – consistency of space-time, birth and death of the Universe, black holes… good choice, Sir Roger! Km traveled: 19,500.
He studied between Freiburg and Bonn, where he also obtained his PhD (1978). He then landed in the States (Center for Astrophysics, Smithsonian-Harvard) and did not miss the opportunity for a coast-to-coast trip from Massachusetts to the University of Berkeley, in California. He then went back to Germany, in Munich precisely, where he is currently the director of the Max Planck Institut für extraterrestrische Physik – a famous institute of “extraterrestrial physics” that, despite the name, does not deal with extraterrestrial life at all. Km travelled: 20,300.
She obtained her Bachelor in physics from MIT in 1987 – ten years after Genzel was there. She completed her PhD at the California Institute of Technology (Caltech). After a brief trip to Arizona, she returned to work in Southern California, at UCLA. Km traveled: 7,000.
I probably noticed this mobility aspect in their biographies because it is the only thing we have in common: in every other respect my career as an astrophysicist does not compare. It is obviously not a coincidence: this kind of professional odyssey is the common denominator of the modern scientist, starting from Galielo Galilei, who moved from Pisa to Padua – where he appreciated the liberal and intellectually stimulating environment – and then from Padua to Florence – where he appreciated the salary being five times higher and without teaching obligations.
The reasons for these moves are manifold, a mixture of vocation – collaborations with new colleagues, access to different structures/resources, etc. – and the requirement linked to the atypical nature of this work. It is easy to fall into the temptation of talking about “brain on the run”, especially in the astrophysics field where the number of PhDs is growing much faster than new jobs. Fonte:Kame Without denying the existence of such a problem, it is perhaps worth counterbalancing the image of the “unhappy wonder researcher” with a different narrative: brains on the road rather than brains on the run. A perspective that could be applied more generally, even outside the world of Astrophysics, to avoid falling into easy stereotypes.
Wasn’t there a time when being a citizen of the world took on positive aspects? Obviously this also implies a series of compromises that not everyone would find acceptable: living on rent, not having parents to help with the grandchildren, being able to eat decent bread only by paying exorbitant amounts. But since these are hard times, why don’t we take a break from contemplating displaced human misery and take a look at the “happy temps” who travel by choice and not to escape from something? This is obviously assuming that winning a Nobel makes you happy and makes you think with fondness of that time in your life when you had to move house every 2-3 years and didn’t have 8 million Swedish krona in your bank account.
I went to look for the CVs of all astrophysicists awarded a Nobel Prize. If I have not miscounted, there are twenty-six people – Andrea Ghez is the only woman – out of a total of about 215 scientists – I say “about” because I am afraid I might have considered Marie Skłodowska Curie twice, and I do not want to recount. For the record, the first astro-Nobel prize was Victor F. Hess in 1936, thirty-five years after the first ever Nobel prize in Physics, awarded to W.C. Röntgen (X-ray pioneer). Hess, like Curie, gives me some problems in accountability, because his discovery of cosmic rays is halfway between Astrophysics and Particle Physics. Despite the experimental error, we can say that since it was established in 1901, the Nobel Prize in Physics has been awarded to an astrophysicist in 10-12% of cases. The percentage rises to a staggering 30% when considering only the results of the 21st century. Except in rare cases, these distinguished astrophysicists have accumulated several miles on their loyalty card, confirming the impression made with Penrose, Ghez, and Genzel (this time listed in descending order of h-index, the bibliographic index that measures the scientific impact of an author’s body of publications). Obviously we are talking about an elite group of scientists who do not necessarily represent the characteristics of the average researcher. But it is interesting to note that even though they earned their PhDs in places of the highest prestige, the next step was to seek a job elsewhere. Of course, one cannot rule out that this was a matter of necessity, but it is legitimate to assume that such bright students would have found an opportunity not to leave. The research system favors such mobility: for example, the European Union has funding schemes in which it is expressly required that the research project be carried out in a state where the beneficiary does not currently reside. The same philosophy applies to the well-known Erasmus program, which in more than thirty years has allowed millions of European citizens to spend a study period abroad.
Hess himself is probably the one who has traveled the least, having spent his career almost entirely in Austria. But even he decided at some point that it was important to change his perspective, and took a couple of sabbatical years to work in the United States. Now that I notice, also Mayor & Queloz – the discoverers of a planet orbiting a Sun-like star – have always stayed in between Lausanne and Geneva: maybe there is something special about the Alps we are not aware of?
Everyone else has studied and worked in at least three different places. Not surprisingly, in most cases these are top-notch institutions: Princeton has hosted the most Nobel Prize winners (7) followed closely by Harvard, California Institute of Technology (Caltech), University of California Berkeley, and Massachusetts Institute of Technology (MIT). It is obviously not only a simple matter of prestige. Each university has different labs and offers different expertise. Berkley, for example, is not as universally famous as Harvard, but it has privileged access to the Keck telescopes, which are at the top of the list of the most important telescopes in the world. It also has an astronomical tradition that starts in the 1870s, shortly after MIT opened its doors, and a good twenty years ahead of Caltech.
It’s worth clarifying three things. First, we are not discussing common telescopes (which are refractor telescopes) but reflecting telescopes, much more powerful. Secondly, we’re narrowing this down to telescopes that observe visible light (or if you prefer, electromagnetic radiation in the optical spectrum with wavelengths between ~300 and ~1000 nanometers) and thirdly, we don’t want to limit ourselves putting them merely in size order. But then again, size of what? We could use the size of the primary mirror, i.e. the larger one, but I do not like this criterion, because size matters, but only up to a certain point. The location, for example, is just as important: the quality of the images taken at >4200 m altitude on Mount Mauna Kea in Hawaii – not bad to work there, right? – is far superior to those that would be obtained with the same instrument at the Gran Canarias Observatory, and not only because of the lower altitude (about 2200 m, so a thicker layer of atmosphere) but also because of the moisture particles that make the image more blurred. And in case you are interested in surprising your friends with breathtaking astronomical photographs (maybe not with your smartphone, please) instead of Hawaii you can also organize a trip to the highlands of Chile – another wonderful location for stargazing. So how to rank them? At the beginning of the 21st century, Benn & Sanchez Fonte:Benn suggested looking at the number of articles published using data collected with a given telescope. At that time, Keck (with its 10 meters diameter primary mirror) was second only to the Hubble Space Telescope (2.4 meters). Also on the podium was the Canada-France-Hawaii Telescope, located a few meters away from Keck, which managed to be competitive despite its “only” 4 meters diameter. At the end of the 90’s however, the ESO (European Southern Observatory, so called because the sponsors are European States but the telescopes are in Chile) Very Large Telescope (VLT) became operative and supplanted the Keck hegemony (on the ground). From a certain point of view this is cheating, since the VLT is not one but a complex of four telescopes, each of 8 m class. Hubble is still unmatched in terms of scientific impact, but we should also keep in mind that maintaining it costs 100 times more than a ground-based telescope. As for the 2020 Nobel Prize in Physics, the research was conducted with both Keck (Ghez) and ESO/VLT (Genzel).
Cambridge is the most visited destination in the Old World, while the only astrophysics laureates affiliated with Oxford (and I’m sorry for the long-standing rivalry here), are Penrose and Sir Martin Ryle. To be fair, Cambridge surpasses Oxford also in the general Nobel count too: 110 vs 56. The State University of Milan appears on the list because it was the scientific birthplace of Riccardo Giacconi – one of the fathers of X-ray astronomy. A special mention to Subramanyan Chandrasekhar (expert in stellar physics) from Madras (India), who obtained a scholarship to Cambridge University, 8200 km far from home. I imagine the trip was much longer at the time, since in 1930 there was hardly a direct flight.
In addition to the constant travels, what attracted my attention is the recurrence of certain places. The Alma Mater of 50% of our samples was one of these universities: Cambridge, Harvard, Berkley, or Caltech – in chronological order of founding. So, if you’re thinking of becoming a famous astrophysicist and winning a Nobel Prize, or you’re thinking of where to send your kids to school, now you know how to increase your chances. And not only because of the quality of the teaching and the research of these schools, but also because even in academia “the sun shines on the righteous”. In fact, nominations for the Nobel Prize are proposed by a group of qualified nominators, who send names to the Nobel Commission. Winners from previous years are included among the nominators, so if you work at the same university as a Nobel Laureate – and you don’t forget to bring them coffee every morning – you have a little more hope that your name will end up on the list of nominees. Others authorized to submit nominations are members of the Royal Swedish Academy of Sciences and the Nobel Committee itself, professors in Physics disciplines at universities in Sweden, Denmark, Finland, Iceland and Norway (trust me, there are only very few of them), and professors in Physics disciplines in other universities chosen by the Academy of Sciences, in order to provide more international coverage. These “other universities” must be at least six. It’s clear though that previous Nobel Laureates play a not insignificant role in the process of selection within the field of astrophysics. This is not always the case for Nobel awards though. For example, the voice of the previous winners in the case of the Nobel Peace Prize is submerged in the souk of nominations that are proposed, among others, by members of any national assembly or government, by professors (emeritus, associate, full professors) of History, Social Sciences, Law, Philosophy, Theology and Religion of any university, and by university rectors and directors of research institutes of Foreign Policy.
Perhaps the reader’s head will spin after all these digressions, and he or she may wish to know a little about the situation in Italy. So let’s conclude this overview by having a look at the situation of Astrophysics in Monnalisa’s home peninsula. Without any claim of completeness, but just to give an anecdotal indication, I downloaded the list of 571 employees and associates of INAF (Italian Institute of Astrophysics) updated to 7/3/2021. The CV is not listed, so one must rely on the geography of names to identify those who have spent part of their careers in other countries. The process is incomplete insofar as it has gone, but despite this, the count of foreign-born names (37 in all) is a robust lower bound because I have verified that these are astrophysicists who have crossed at least one border (it is unknown whether to stay permanently in Italy or just for a limited period). It is also a good indicator of diversity within INAF: these 37 people studied abroad and it is fair to say that they bring an alternative contribution and international perspective within the research body. Foreign researchers are somehow different from Italian researchers that trained in Italy and then moved abroad for a few (or many) years, before returning home. 37 out of 571 means 6%. Honestly, I expected worse, and intuitively I would expect much higher percentages for France (INSU-CNRS), but I can’t find any data.
I did a similar thing for the 162 PhD students scattered around the country with an INAF affiliation. Twenty-six have a foreign-born name. They would represent 16% of those enrolled, a percentage to be handled with caution. It is not, however, far from the ~20% of international students in the United Kingdom, a country which can count on the much greater North American (for language reasons) and Chinese pools (Chinese students make up to 30% of total student arrivals from across the Channel).
And with this last stop, the time has come to end our journey. Although on rickety tracks, we have touched on several aspects of scientific mobility. I have not proved any thesis but I hope I have provided some food for thought. And if not, I will simply end with Jack Kerouac’s famous phrase: