Sagan

December 23, 2006

Unsurprisingly, I am late for Carl Sagan Blog-a-thon(See here for a list of posts) . It’s ten years since sagan died.

(Hmm.. Lately my blog has reduced to a series of posts in memorial of different anniversaries ! I promise my readers that I will try to come up with something else for the next post..)

Carl Sagan affected so many of us in so many different ways. I still remember reading Cosmos [Amazon] when I was younger and being awed by the wonder of it all. If you hadn’t noticed before, the quote just beneath this blog’s title comes from sagan.

Sagan is no more. But the spirit which drove him still survives in his wife Ann Druyan who is equally unflinching in supporting science and its popularisation. I could clerly recognise that spirit, for example, when I heard Druyan answer a question in the middle of a discussion about science and religion.

The greatest legacy of Sagan, in my eyes, is the realisation that a culture without science is as impoverished as a culture without art or music. Given how few people realise that fact (with my limited experience, I can safely assert that even most science students don’t realise it) world really needs more sagans today.

These are two videos of sagan I could get hold of at youtube.
Carl Sagan on Alexandria
Part 1

Part 2

You might also like to read this post – “Casting out the demons” by Jennifer Oullette.

2006 – Year of Maxwell ?

December 17, 2006

(Crossposted to BlogPhysica )

maxwell_j_c.jpg
I just realised(via a physicsweb article ) that this year is supposed to be the 175th anniversary of the birth of James Clerk Maxwell. Quite in the year to realise it I suppose 😉

So what impression of Maxwell would you have gained if you had met him in his prime, as a young Scottish undergraduate Donald MacAlister did in Cambridge in 1877? You would surely have been charmed, but perhaps also surprised to meet – as MacAlister put it – “a thorough old Scotch laird in ways and speech”. As the proprietor of an 1800 acre Scottish estate, Maxwell had all the qualities of the better kind of Victorian country gentleman: cultivated, considerate of his tenants, active in local affairs, and an expert swimmer and horseman too.

Few would have guessed that this “Scotch laird”, so disarmingly old-fashioned even in 1877, was a scientist whose writings remain astonishingly vibrant in 2006 and the greatest mathematical physicist since Newton. In addition to his work on electromagnetism, Maxwell also contributed to eight other scientific spheres: geometrical optics, kinetic theory, thermodynamics, viscoelasticity, bridge structures, control theory, dimensional analysis and the theory of Saturn’s rings. He also worked on colour vision, producing the first ever colour photograph…

Even if his achievements are somewhat overshadowed in the public’s eye by those of Einstein, whose successes were marked by a great series of events last year, it is a measure of Maxwell’s standing that 2006 – the 175th anniversary of this birth – has been dubbed Maxwell Year.

Anyway, this gives me an excuse to return back to writing about Maxwell about whom Feynman famously remarked

From a long view of the history of mankind — seen from, say, ten thousand years from now, there can be little doubt that the most significant event of the 19th century will be judged as Maxwell’s discovery of the laws of electrodynamics. The American Civil War will pale into provincial insignificance in comparison with this important scientific event of the same decade.

I guess I should add that the revolt of 1857 would also pale into provincial insignificance….

Since I have already linked once to poems by Maxwell , I will now link to one of the oldest biographies of Maxwell – the one written by Lewis Campbell and William Garnett (Link to PDF file).

The 1997 Digital Preservation of “The Life of James Clerk Maxwell”

..There are very few biographies of Maxwell. The most comprehensive biography was written by a life-long friend, Lewis Campbell with help from William Garnett. It is considered a primary historical reference on Maxwell. Published in 1882, shortly after Maxwell’s death, it is today found only in the rare book rooms of large libraries. However, now the entire text of the book with figures included is available here…

It is a long and interesting book filled with a lot of anecdotes written at a time when mechanical theories of ether were still in vogue. This of course, does not undermine its significance in History of physics . …

To quote what Weinberg wrote three years ago in his “Four Golden Lessons” addressed to a Scientist

Finally, learn something about the history of science, or at a minimum the history of your own branch of science. The least important reason for this is that the history may actually be of some use to you in your own scientific work. For instance, now and then scientists are hampered by believing one of the over-simplified models of science that have been proposed by philosophers from Francis Bacon to Thomas Kuhn and Karl Popper. The best antidote to the philosophy of science is a knowledge of the history of science.

More importantly, the history of science can make your work seem more worthwhile to you. As a scientist, you’re probably not going to get rich. Your friends and relatives probably won’t understand what you’re doing. And if you work in a field like elementary particle physics, you won’t even have the satisfaction of doing something that is immediately useful. But you can get great satisfaction by recognizing that your work in science is a part of history.

Salam

November 21, 2006

(Crossposted to BlogPhysica )
salam.jpg

Ten years ago, on 21st of Novomber, 1996, Abdus Salam, who was among the co-founders of the Standard Model died at his home at Oxford.

For those who don’t know him, he was one of the recipient of the Nobel Prize in Physics(1979) “for their contributions to the theory of the unified weak and electromagnetic interaction between elementary particles, including, inter alia, the prediction of the weak neutral current” in short, for what physicists call the Glashow-Salam-Weinberg Model (which along with Quantum Chromodynamics and Classical General Relativity form the foundations on which all physics stands).

Was just reminded of him as I was doing some calculation with the Salam-Strathdee Superfield Formalism in (Supersymmetric extension of) Glashow-Salam-Weinberg Model. It is amusing how pursuit of science brings back names from far away…

As Salam himself mused before beginning his Nobel Lecture

Scientific thought and its creation is the common and shared heritage of mankind. In this respect, the history of science, like the history of all civilization, has gone through cycles. Perhaps I can illustrate this with an actual example.

Seven hundred and sixty years ago,a young Scotsman left his native glens to travel south to Toledo in Spain. His name was Michael, his goal to live and work at the Arab Universities of Toledo and Cordova, where the greatest of Jewish scholars, Moses bin Maimoun, had taught a generation before.

Michael reached Toledo in 1217 AD. Once in Toledo, Michael formed the ambitious project of introducing Aristotle to Latin Europe, translating not from the original Greek, which he did not know, but from the Arabic translation then taught in Spain. From Toledo, Michael travelled to Sicily, to the Court of Emperor Frederick II.

Visiting the medical school at Salerno, chartered by Frederick in 1231, Michael met the Danish physician, Henrik Harpestraeng – later to be-come Court Physician of King Erik Plovpenning. Henrik had come to Salerno to compose his treatise on blood-letting and surgery. Henrik’s sources were the medical canons of the great clinicians of Islam, Al-Razi and Avicenna, which only Michael the Scot could translate for him.

Toledo’s and Salerno’s schools, representing as they did the finest synthesis of Arabic, Greek, Latin and Hebrew scholarship, were some of the most memorable of international assays in scientific collaboration. To Toledo and Salerno came scholars not only from the rich countries of the East and the South, like Syria, Egypt, Iran and Afghanistan, but also from developing lands of the West and the North like Scotland and Scandinavia. Then, as now, there were obstacles to this international scientific concourse, with an economic and intellectual disparity between different parts of the world. Men like Michael the Scot or Henrik Harpestraeng were singularities. They did not represent any flourishing schools of research in their own countries. With all the best will in the world their teachers at Toledo and Salerno doubted the wisdom and value of training them for advanced scientific research. At least one of his masters counselled young Michael the Scot to go back to clipping sheep and to the weaving of woollen cloth.

In respect of this cycle of scientific disparity, perhaps I can be more quantitative. George Sarton, in his monumental five-volume History of Science chose to divide his story of achievement in sciences into ages, each age lasting half a century. With each half century he associated one central figure. Thus 450 BC – 400 BC Sarton calls the Age of Plato; this is followed by half centuries of Aristotle, of Euclid, of Archimedes and so on. From 600 AD to 650 AD is the Chinese half century of Hsiian Tsang, from 650 to 700 AD that of I-Ching, and then from 750 AD to 1100 AD – 350 years continuously – it is the unbroken succession of the Ages of Jabir,Khwarizmi, Razi, Masudi, Wafa, Biruni and Avicenna, and then Omar Khayam – Arabs, Turks, Afghans and Persians – men belonging to the culture of Islam. After 1100 appear the first Western names; Gerard of Cremona, Roger Bacon – but the honours are still shared with the names of Ibn-Rushd (Averroes), Moses Bin Maimoun, Tusi and Ibn-Nafi-the man who anticipated Harvey’s theory of circulation of blood. No Sarton has yet chronicled the history of scientific creativity among the pre-Spanish Mayas and Aztecs, with their invention of the zero, of the calendars of the ‘moon and Venus and of their diverse pharmacological discoveries, including quinine, but the outline of the story is the same – one of undoubted superiority to the Western contemporary correlates.

After 1350, however, the developing world loses out except for the occasional flash of scientific work, like that of Ulugh Beg – the grandson of Timurlane, in Samarkand in 1400 AD; or of Maharaja Jai Singh of Jaipur in 1720 – who corrected the serious errors of the then Western tables of eclipses of the sun and the moon by as much as six minutes of arc. As it was, Jai Singh’s techniques were surpassed soon after with the development of the telescope in Europe. As a contemporary Indian chronicler wrote: “With him on the funeral pyre, expired also all science in the East.” And this brings us to this century when the cycle begun by Michael the Scot turns full circle, and it is we in the developing world who turn to the
Westwards for science. As Al-Kindi wrote 1100 years ago: “It is fitting then for us not to be ashamed to acknowledge and to assimilate it from whatever source it comes to us. For him who scales the truth there is nothing of higher value than truth itself; it never cheapens nor abases him.”

And by the way, do read the whole thing – if not for anything else atleast for the Pauli Stories 🙂

…The hut also contained Professor Villars of MIT, who was visiting Pauli the same day in Zurich. I gave him my paper. He returned the next day with a message from the Oracle;
“Give my regards to my friend Salam and tell him to think of something better”. This was discouraging, but I was compensated by Pauli’s excessive kindness a few months later, when Mrs. Wu’s, Lederman’s and Telegdi’s experiments were announced showing that left-right symmetry was indeed violated and ideas similar to mine about chiral symmetry were expressed independently by Landau and Lee and Yang. I received Pauli’s first somewhat apologetic letter on 24 January 1957.

Thinking that Pauli’s spirit should by now be suitably crushed, I sent him two short notes I had written in the meantime. These contained suggestions to extend chiral symmetry to electrons and muons, assuming that their masses were a consequence of what has come to be known as dynamical spontaneous symmetry breaking. With chiral symmetry for electrons, muons and neutrinos, the only mesons that could mediate weak decays of the muons would have to carry spin one.

Reviving thus the notion of charged intermediate spin-one bosons, one could then postulate for these a type of gauge invariance which I called the “neutrino gauge”. Pauli’s reaction was swift and terrible. He wrote on 30th January 1957, then on 18 February and later on 11, 12 and 13 March: “I am reading (along the shores of Lake Zurich) in bright sunshine quietly your paper…”
“I am very much startled on the title of your paper ‘Universal Fermi interaction’ …For quite a while I have for myself the rule if a theoretician says universal it just means pure nonsense. This holds particularly in connection with the Fermi interaction, but otherwise too, and now you too, Brutus, my son, come with this word. …”….

Although he signed himself “With friendly regards”, Pauli had forgotten his earlier penitence. He was clearly and rightly on the warpath.

… I must admit I was taken aback by Pauli’s fierce prejudice against universalism – against what we would today call unification of basic forces – but I did not take this too seriously. I felt this was a legacy of the exasperation which Pauli had always felt at Einstein’s somewhat formalistic attempts at unifying gravity with electromagnetism – forces which in Pauli’s phrase “cannot be joined – for God hath rent them asunder”….

There is something more to Salam’s Legacy than Electroweak Unification. And of course, I’m thinking of the Abdus Salam International Centre for Theoretical Physics (ICTP) at Italy. And in a more subtle way, He also stands for a struggle – a struggle to provide the students from the third world(and in particular Pakistan) the joys of science…

To Quote Hoodhboy

In interacting with Salam, I could see that two strong passions governed his life. Physics research occupied him intensely; his mind would lock onto a problem making him oblivious to all else. He would engage only the most challenging and difficult problems of the field, problems that only the greatest can dare try. The elegance of his solutions were startling, as for example in his brilliant creation of what are called superfields. Without this powerful mathematical concept, physicists would have a very hard time to progress beyond a certain point in grappling with the basic laws of nature.

Salam’s other passion was Pakistan. I have never been able to understand why he was so dedicated to the country of his birth given that he was virtually ostracised there, being an Ahmadi. I can remember that when the members of the physics department at Quaid-i-Azam University sought to invite him for a lecture after he received the Nobel Prize, the idea was vetoed when the student arm of a vociferous religio-political party threatened to use violence if he came to the campus. In spite of this and much more, Salam was never embittered and he never gave up trying to do whatever he could for his country.

So on this day, let us wish that hundreds of years hence, let nobody speak of him the way Salam spoke of Jai Singh – let nobody say “With him .. expired also all science in ” Pakistan .