Einstein, de Valera and the Institutes for Advanced Study

Is there a collective noun for a roomful of professors? A great many of the most senior figures of Irish academia turned up in Trinity College Dublin on Saturday night to hear the annual statutory lecture of the School of Theoretical Physics of the Dublin Institute of Advanced Studies.

The lecture, titled “No excuses in paradise: the past, present and future of the institutes for advanced studies” (see poster here) was a fascinating talk on the history and purpose of the Institutes for Advanced Study at Princeton, Dublin, Paris and elsewhere. It was given by Professor Peter Goddard, the current director of the famous Institute for Advanced Study at Princeton in the US. This institute, one of the most prestigious research centres in the world, hosted staff such as Einstein, Godel, Oppenheimer, Freeman Dyson and Ed Witten and became the prototype for similar institutes around the world. Peter Goddard himself is extremely well-known as one of the early pioneers of string theory.

The  speaker started by tracing the initial idea by the American educationalist Abraham Flexner in the 1920s to seek funding for an Institute for Advanced Study in the US that could compete with research centres in Germany such as that in Gottingen. The plan was to create an elite American ‘graduate university’ –  a university that did not teach at undergraduate level but focused on research and on the training of researchers. Of course such an institute could only be staffed by the best of the best, and Einstein, already a world figure in science, was approached on one of his periodic visits to Caltech. Worried about the rise of the Nazis, Einstein quickly agreed. You can read more about this story here, but Prof Goddard showed a wonderful slide showing the famous issue of the New York Times with the headline: ‘Einstein to set up new school’.

Einstein in his office at IAS

The speaker then explained how during the war the Irish premier Eamon de Valera, a former mathematician, decided a similar institute would be of benefit in Ireland. Due to economic constraints, it was settled that the institute would deal with theoretical physics (as there were great advances being made in this field and it required no expensive equipment) and with Celtic studies (also not very expensive and of nationalist interest). On the advice of Einstein, de Valera approached Schroedinger, the father of wave mechanics, to persuade him to come to Ireland to direct the institute.

This part of the story was well-known to an Irish audience but the speaker gave a very nice sketch of the history – Schroedinger did come in 1940 and spent many years at the Dublin IAS, followed by other prestigious theoreticians such as Heitler, Lanzcos and Synge. The institute became a great success internationally, attracting regular visits by famous physicists such as Paul Dirac. Indeed, some nice slides concerning Dirac’s visits were shown, not least a menu demonstrating the attraction of Ireland during wartime. Another slide showed a comment by Dirac, expressing surprise that the Irish Prime Minister had time to sit through a whole mathematics conference! All in all, it was a lovely overview of the history of the Dublin IAS and included a nice reference to Lochlainn’s work (it turns out Goddard collaborated quite a bit with Lochlainn in the early days of supersymmetry) .

Nobel laureates Dirac, Heisenberg and Schrodinger in Sweden

The speaker then explained how the American idea was imported back to continental Europe, notably at IHES in Bures-sur-Yvette just outside Paris (set up in 1958). This institute is also highly regarded in the world of academia, thanks to the work of mathematicians such as Alain Connes and the late Louis Michel. There are also informal links between the institutes – many of the professors in the audience had spent time at more than one (in my own family we have fond memories of years spent at both the Princeton and Paris institutes as well as Dublin).

The lecture finished with a brief discussion of the role of such research institutes. In a world dominated by the technological application of science, it is sometimes hard to persuade people of the importance of enquiry for it’s own sake – ‘the usefulness of useless knowledge’. Of course, one answer to this is that we don’t know which part of scientific enquiry will prove technologically useful (look at Boolean algebra or the development of the web at CERN). However, a deeper answer is that knowledge and the pursuit of knowledge will always be important for their own sake. The professor summed up with the best quote of the night: ‘the thing about a scholar’s paradise is that there are no excuses for failing to do something important!’

So have the institutes been a success overall and should they continue? As a student, I often heard certain university staff mutter darkly that precious little work went on there – however such comments rarely came from staff at the highest levels. It’s worth noting that Saturday’s speaker was introduced by Professor Samson Shatashvili, the well-known string theorist who directs the Hamilton Mathematics Institute , a research institute that functions within Trinity College. Prof Goddard didn’t compare the role of such institutes with the institutes for advanced study directly, but I think his historical account demonstrated that the latter still have an important role to play. As regards the Dublin IAS, I should have said that the lecture above took place in the middle of a conference to celebrate the 60th birthday of Professor Werner Nahm, a noted theorist at the Dublin IAS. A measure of the stature of Werner, and of the continuing prestige of DIAS, can be seen from the list of speakers in the conference program here. Another indication of the continuing success of DIAS was the preponderance of well-known international figures on Saturday night such as Shatashvili, Nahm, Goddard and Frohlich – not to mention the mathematician Micheal Atiyah and a quiet man in the back row who I later realised was Peter Higgs (yes, he of the elusive boson).

The school of theoretical physics (DIAS) on Burlington  Road

Faraday Institute summer school

I spent all of last week at a summer school on science, philosophy and religion hosted by the Faraday Institute of St Edmund’s College, Cambridge. I found the course absolutely excellent and have tried to summarize most of the talks on a daily basis as the conference progressed (see last four posts below). You can also find a list of speakers and talks on the conference website .

All that is left to do is to make a few general observations. I found the school quite exceptional, a real treat for anyone with an interest in the history and philosophy of science, and its impact on religion (and vice versa). A different topic was tackled each day, from historical and philosophical interactions between science and religion on Tuesday to Big Bang cosmology on Wednesday, from the theory of evolution on Thursday to ethical challenges in contemporary science on Friday.  Each day would begin with an introductory overview of the basic science (or history), followed by talks on slightly more specific subjects. Each talk would finish by exploring the philosophical and theological implications of the science.

All the speakers kept good time, leaving 30 minutes of question/answer session after each talk. This definitely made for good audience participation. This was followed by a panel discussion every evening on questions raised during the day.

Note: videos of the talks will be available on the multipage  multimedia page of the Faraday website from mid-September only, apologies for misinformation in earlier posts.

St Edmund’s college, Cambridge

Other reasons for the success of the conference were

1. Fantastic environment; it’s hard to beat Cambridge on this, especially with everyone staying in the same college

2. All the talks were in the same venue, a nice small conference room that holds about 50.

3. Interdisciplinary nature; since the subject matter spanned science, history of science, philosophy and theology, none of the talks were too specialised, the bugbear of most scientific conferences

4. All the talks were by world-class researchers, well used to giving public talks on their subject – a treat for anyone interested in the communication of science.

5. No parallel sessions; since everyone was at the same talk, it made for great discussions over dinner.

Coffee time outside the conference room

A number of my colleagues have expressed reservations about the course, pointing out that it is funded by the Templeton Foundation. All I can say is that all of the speakers presented the science or history in an unbiased way. The week was a treat in the history and philosophy of science, even for those with no interest in religion. That said, it was fascinating hearing renowned theologians criticizing the fundalmentalist positions taken by some religions (and atheists). No-one can demolish the Intelligent Design argument quite as comprehensively as an eminent theologian! Another good example of the impartiality of the conference can be seen in the fact that the scientific work of Richard Dawkins was cited on several occasions and two of his books were on sale  on the conference table..

Update

Speak of the devil! About 10 minutes after writing the above, I walked right past Richard Dawkins himself. He was walking up the back drive into Clare College just as I was wandering out. I wonder if he is giving a talk here in Cambridge? I was dying to ask, but he looked a bit tired and had luggage with him. Possibly not a good moment for questions from random strangers..

Last day at Cambridge conference

Today was the last day of the Faraday Institute summer school (see posts below) and it was devoted to ethical challenges in contemporary science.

The day started with an excellent overview of the whole area of ethics by Dr Cherryl Hunt of the University of Exeter. Dr Hunt set the stage for the day by explaining concepts such as ethical relativism, ethical objectivism and ethical absolutism. She then went on to discuss the differences between naturalistic, utilitarian and deontological positions in an ethical context.

Dr Cherryl Hunt on ethics

Commenting on why ethic challenges are often involved the biological sciences in particular, Dr Hunt explained that the biosciences tend to throw up interesting questions such as

- human improvement: do we need it?

- the mixing of animal and human genes; should we do it?

- genetically modifying plants and animals: is it dangerous?

Dr Hunt  addressed each of these in turn. She also discussed another dilemma, the ethics of environmental challenges. Going over the different positions of many religions, she contrasted the ‘dominion over the earth’ viepoint with that of the ‘stewardship of the natural world’.  This was a fascinating talk and you should be able to get the slides and video on the Faraday Institute website in a few days.

The second talk, given by Prof Keith Fox, Professor of Biochemistry at the University of Southampton, dealt with the specific topic of ‘Genetic engineering: How Far Should We Go?’

Keith started with a great overview of  DNA, genes and genetic code, making some simple points :

- the same copy of DNA exists in every cell

- genes make up 2% of DNA

- the genetic code is universal

- there is no such thing as a human gene

- all life clearly arises from a single source

This was followed by a quick review of landmarks in modern genetics such as recombinant DNA (1972), transfer into E-coli (1973), first genetically modified animals (1976), first genetically modified plants (1983) etc. Then followed a detailed discussion of animal-animal and human-animal gene transfer. I won’t give details, but I particularly enjoyed a discussion of GM foods. A familiar issue here is the pubic misunderstanding of science: the public distrust of GM foods is in marked contrast to the scientific consensus, making it very difficult for GM technology to progess.

Dr Keith Fox on the podium

After lunch, we were treated to a very different sort of lecture:, a lecture on the nature of personhood and the ethical challenges raised by medical technology, given by Professor John Wyatt, Professor of Neonatalogy at University College Hospital London.

Prof Wyatt started with a wonderful slide, a picture of a tiny, prematurely-born baby hooked up to an astonishing number of tubes in ICU at his hospital. Having brought the audience to the human side of things he gave a few interesting statistics:

- about 50% of such babies will be absolutely normal

- about 20% suffer severe mental and physical difficulties

- society values such lives, given the investment in medical treatment

On the other hand, Prof Wyatt explained that, in the same hospital , many parents are offered the option of abortion for babies with handicaps or deformities. In particular, about  90% of unborn babies with Down’s Syndrome are aborted, a truly shocking statistic. Given that it is often the same doctors, you can see the ethical maelstrom. This issue is set to get worse, with the onset of pre-natal tests which may give a full analysis of the DNA of unborn child..

There followed a detailed discussion of the nature of personhood, starting with the views of the philosopher Peter Singer. Dr Wyatt showed the weaknesses of the Singer position by considering examples from brain-damaged adults to dementia. He also emphasised the issue of dependence – how it is intrinsically human to be dependent, from the youngest infant to the oldest person-our natural condition far from an abherration.( ‘We are designed to be burdens!) This was an outstanding talk but I won’t attempt to summarize it further..you can see the video on the conference website or go and buy his book!

The last talk of the day was another talk by Dr Cherryl Hunt (see above), this time on the particular subject of the ethics of stem cell research. Starting with simple definitions such as totipotent cells (can make all cell types, can grow into embryo), pluripotent cells (can make many cell types  but can’t grow embryos) and multipotent cells (can make few cell types), Dr Hunt explained the huge advantages of embryonic stem cells. She went on to describe the ethical challenges concerning the use of these cells, contrasting the utilitarian to deontological viewpoints discussed this morning.

I won’t give a proper review here, but in the discussion afterwards, I was struck by the common sense approach adopted by the speaker and most of the audience, representatives of many religions and none. Essentially, many felt that the fact that nature disposes of about 80% of fertilized eggs for a variety of reasons implies that we should probably not be too absolute in our view of the status of embryonic stem cells. There was also the issue of spares: in IVF, unused embronic cells are routinely disposed of, so  is it not better to use them for the good of mankind?

That was the last talk of the conference; again a recording will soon be available on the Faraday website. As on other days, the day’s presentations were followed by a plenary panel discussion of questions raised by the talks. Overall, this was a fantastic week of highly interesting talks, see review tomorrow. Right now, it’s time for the conference dinner at High Table!

Note: videos of the talks will be available on the multipage  multimedia page of the Faraday website from mid-September only, apologies for misinformation in earlier posts.

Evolution at Cambridge

Today was evolution day at the Faraday summer school (see posts below), with a number of fascinating talks on the theory of evolution.

First up was Professor Stephen Freeland of the University of Maryland. An interesting aspect of Stephen’s talk was that it was delivered in realtime (by Skype) from Hawaii! With his slides projected on the conference screen and his voice and image on a nearby computer, one quickly forgot he was not actually in the room.

Stephen’s first talk was a super overview of the modern status of the theory of evolution by natural selection, explaining how advances in microbiology and genetics have strengthened and deepened the theory. One interesting aspect of this talk was Stephen’s belief in the fallacy of human supremacy: he sees humans as far from the top of the chain of life,  as often depicted. Indeed, he showed that a great deal of the common portrayal of man at the pinnacle of the evolutionary tree really arises from pre-Darwinian theory!

Stephen also gave a talk on astrobiology, the study of life on other planets. Much of astrobiology is concerned with the study of the emergence of life in the earliest years of earth, but there was a fascinating overview of the factors need for life elsewhere. I particularly enjoyed his discussion of attempts to quantify the Drake equation, an equation that attempts to describe the probability of there being intelligent life on other planets (more on this later).

Denis Alexander in conversation with Stephen Freeland

Next up was a fascinating talk by Simon Conway Morris on ‘Evolution and the Inevitability of Man’. This was a superb overview of the theory of convergence in evolution, a theory Simon has pioneered. Essentially, it concerns the fact that many complex organs such as the camera eye have evolved not once, but several times. Simon went on to explain why he evolutionary convergence may render the emergence of intelligent life not just likely but inevitable, and sees the evolution of intelligent life as an ultimate and inevitable result of the process, in marked contrast with the previous speaker.

This was followed by a superb talk by Keith Fox, Professor of Biochemistry at Southampton University on ‘Creation and Evolution’. Essentially, Professor Fox gave a detailed exposure of scientific flaws in young earth creationism, and in intelligent design. He finished with a description of theistic evolution. In a way, this talk was the most archetypal of the week – a careful rebuttal of the literal positions of fundamentalists by a highly educated scientist and theologian.

The final talk of the day was a salutary lesson in biblical studies by Dr Ernest Lucas. Dr Lucas gave an outline of the challenge for interpreters of any text: when does one need a literal interpretation and when does one need a figurative one?  These are normally decided on factors such as

What kind of language is used in the text?

What kind of literature?

What kind of audience?

What is the purpose of the text?

There followed a detailed discussion of the interpretation of the Book of Genesis, with Dr Lucas concluding that a figurative rather than literal interpretation is clearly called for.  Again, this was a strong attack on fundamentalism by a renowned theologian, absolutely fascinating.

The day finished with a planary question-and-answer session chaired by Dr Denis Alexander, with Stephen participating by Skype link. Again, I was astonished how well it worked.

Simon, Stephen and Dennis in panel discussion

Cosmology day at Cambridge

Today was cosmology day at the Faraday conference (see above). Due to a mishap in scheduled speakers, course director Rodney Holder gave an impromptu talk on ‘God, the multiverse and everything’. Essentially, this was two talks: an introduction to Big Bang theory, inflation and the multiverse, followed by a discourse on the philosophical and theological implications of the multiverse model. It was a super overview and highlighted many of the limitations of the proposition of the multiverse.

That said, it must be remembered that the mutiverse model is at a very early stage of development (indeed, it seemed to me that a separate introductory talk on the status of inflation and the mutiverse might have been helpful for non-physicists in the audience). You can find Rodney’s excellent book on the subject here

Rodney’s talk was followed by a presentation by the renowned Irish philosopher Ernan McMullin on ‘Fine tuning and the ‘The anthropic principle’. This was an excellent talk which I won’t attempt to summarize (it will be soon be available on the Faraday website). It culminated in an outline of 4 main explanations for fine tuning

1.Chance

2. Almost all fine-tuning constants found to be related by future theories (bearing in mind that we know GR and qt are incomplete)

3. Anthropic argument

4. Arguments from natural theology

Ernan in full flight

Later in the day, we had a fascinating talk on ‘Habitable exoplanets and the implications for human significance’ by Jennifer Wiseman, director of the search for exo-planets at NASA. This was a super overview of the methods of the search for earth-like planets orbiting suns, either our own or in other solar systems and the recent successes. The talk finished with a brief overview of the philosophical implications of the discovery of life on other planets.

This was a fascinating talk, but I can’t help thinking that there is a fundamental paradox here: given the size of the universe, it may well be that there are lots of planets in the right zones, all teeming with life – but we will probably not find them, due to the same size of the universe! Jennifer answered this by pointing out that the rate of discovery is very exciting – just think of the excitement if we did find one in the right zone and it did have life!

As ever, the day finished with panel discussion, where the speakers answered a variety of questions based on all the talks.

Science, philosophy and religion at Cambridge

I’m spending this week in St Edmund’s College of the University of Cambridge, attending the Faraday Institute summer school on science, philosophy and religion. So far, the course is a feast in the history and philosophy of science, just as last year (see posts on last year’s summer school in July 2008 section).

This morning started with an excellent talk on ‘The Reception of Darwinism’ by renowned historian Prof John Hedley Brooke that posed three main questions. What shifts in attitude resulted from Darwin’s work? What information exists to add to conventional accounts of debates such as the Huxley-Wilberforce debate? Does it make sense to say that Darwin’s theory led to the death of God? I won’t attempt to summarize the talk here, but a video of it will be available on the Faraday website in a few days.

Next we had a talk on ‘Rationality in Science and Religion’ by Roger Trigg, followed by a talk on ‘Islam and Science Yesterday’ by Prof Nidhal Guessom of the University of Sharjah, UAE. Roger’s talk was a highly appropriate for the first day, setting the stage with definitions of concepts such as realism, materialism, relativism, naturalistic methodology etc. Nidahl’s talk was a fascinating account of the history of Islamic science, not merely as curators of Greek classicism but as innovative scientists – accompanied by a careful discussion of the reasons for the gradual decline of Islamic science.

For me, the tour- de-force of the day was a fantastic talk on the history of mediaeval science by the Oxford historian Allan Chapman: ‘Mediaeval cosmology and the Church’. Essentially, Chapman’ s thesis was that the ‘Dark Ages’ is a misnomer, created by a revisionist Protestant view of Catholic science in the middle ages (‘those dark and monkish times’ – Hooke). Chapman made his case by giving a superb overview of science from 600 AD to 1400, describing the advances made from optics to astronomy, and the contributions of figures such as William of Ockham, d’Oresmene,  Nicholas of Cusa and Bernhardt Walther.

Of course, this thesis leads to an obvious question – if the Dark Ages were not so dark, why did it take so long for the heliocentric model to emerge? (my question). Chapman had a great answer – because no-one suspected the Ptolemy model was wrong! After all, most of the predictions of Ptolemny’s geocentric model were more or less accurate!!

I love this theme, and I’m sure it’s typical in science. The most difficult scientific theories to refute are those that are almost correct -or make predictions that re almost correct – simply because no-one suspects they need fixing! True from the limits of Newton’s gravity to the discovery of the elctroweak interaction!. Thought for the day…

Al in all, a super first day. As usual, each talk is a superb example of how to communicate science. After each talk, there is 30 mins of Q&A after every talk, leading to great discussions. After tea, there is a plenary panel discussion, with questions raised during the day discussed.

Course director Rodney Holder (far left) chairs a panel discussion with Allan, Niddaahl and Ernan (L-R)

150th anniversary of Tyndall’s greenhouse effect

Every scientist knows that this year marks the 150th anniversary of the publication of Darwin’s ‘On the Origin of Species’, but not so many may be aware that another scientific breakthrough occurred that year. In 1859, the Irish physicist John Tyndall discovered that certain gases – carbon dioxide and water vapour in particular – absorb infra-red radiation. The discovery was established over a few short weeks, but it provided an explanation for the greenhouse effect, one of the great puzzles of science.

The Irish Times have accepted a piece I have written on Tyndall for their Irishman’s Diary slot next month. I like this column- it is a unique feature of The Irish Times, comprising an 800-word essay prominently displayed on the op-ed page, written by the house journalist 3 days a week and by a freelance writer on other days. I have written a few diaries on various Irish scientists in the past (see My Articles) and I hope one day to publish the ‘Science Diaries’ as a collection of essays.  Below is a draft of what I intend to say on Tyndall:

**********************************

John Tyndall: celebrated Irish scientist who discovered the greenhouse effect

Many readers will know that this year marks the 150^th anniversary of the publication of Darwin’s ‘On the Origin of Species’. Another breakthrough occurred in science that fateful year, this one with an Irish connection. The discovery attracted much less attention than Darwin’s theory of evolution at the time, but it has become one of the hottest topics in science today (literally).

In July 1859, the Irish physicist John Tyndall, one of the great scientists of the 19^th century, established that certain atmospheric gases absorb heat quite strongly. This innocuous-sounding discovery was established over a few short weeks, but it provided the solution to one of the great riddles of science: the famous ‘greenhouse effect’.

The greenhouse effect was first proposed by the French polymath Joseph Fourier, almost a century before Tyndall’s experiments. Fourier had wondered how the earth maintains its warm temperature, and he speculated that while heat from the sun passes easily through our atmosphere on the way to earth, heat radiated outwards by the warm earth must somehow be trapped in the atmosphere. The hypothesis was highly controversial, as it was widely assumed that gases are transparent to heat.

Tyndall, a fierce proponent of the new experimental method of science, devised a series of simple experiments to test Fourier’s hypothesis.  Working in the dusty basement of the Royal Institution in London in the summer of 1859, he soon established that, while most gases are indeed transparent to light and heat, some gases – carbon dioxide and water vapour in particular – can absorb heat energy at certain wavelengths. As traces of each gas were known to exist in the earth’s atmosphere, the puzzle of the earth’s temperature was solved.

How did an Irish scientist come to make such an important discovery? John Tyndall was born in Leighlinbridge, County Carlow in 1820, the son of an RIC officer and land agent. On completing his schooling under renowned local teacher John Conwill, he started his professional career as a surveyor for the Ordinance Survey of Ireland.  He was soon transferred to a position with the Ordinance Survey in Lancashire, England, but became interested in the new experimental sciences of physics and chemistry emerging in Germany. He moved to Germany in 1848 to study under the famous experimentalist Robert Bunsen at the University of Marburg, returning to England with a PhD in experimental science in 1851. By 1853, he had been appointed Professor of Natural Philosophy at the Royal Institution, a position previously held by the renowned scientist Micheal Faraday.

Tyndall remained at the Royal Institution for the rest of his career, making important discoveries in diverse areas of science, from magnetism to optics, from the physics of sound to the behaviour of bacteria. He is probably best known for ‘Tyndall scattering’, the scientific explanation for why the sky is blue. A keen mountaineer, he became interested in the science of glaciers and made several important discoveries concerning their behaviour. He became extremely well-known in Victorian England as a public communicator of science and was a prominent member of the ‘X Club’, an influential group of prominent scientists who defended evolution and other new scientific theories from religious dogma.

Tyndall’s verification of the greenhouse effect was accepted by the scientific establishment, but not regarded as a matter of vital importance. He and his colleagues were aware of the output of Victorian England’s factory chimneys, but no-one drew a link between this pollution and the greenhouse effect.

Nowadays, evidence has emerged that the average temperature of the earth and its oceans has been gradually rising since the industrial revolution. Despite many uncertainties, the scientific consensus is that this global warming is associated with an increase in carbon dioxide in the atmosphere, an increase that has been produced by human activities such as industry and transport. The discovery has led to concerted international efforts to agree on targets for reducing carbon emissions worldwide, a process that is only just beginning.

What would Tyndall make of today’s climate problems? Like most scientists of his era, he would probably find it difficult to grasp that humans could have such a global effect on nature. On the other hand, he would be greatly depressed by the shrinking of his beloved glaciers. Above all, he would be astonished to find that, of all the scientific discoveries he made, the work he did in the summer of 1859 has become a major preoccupation of 21^st century science.

Today, the work of this great Irish scientist is commemorated by the annual Tyndall lecture of the Institute of Physics, the Tyndall Centre for Climate Change Research in the UK, the Tyndall National Institute in Cork, Mount Tyndall in California and the Tyndall glacier in Chile.

*********************************

John Tyndall: celebrated Irish scientist who discovered the greenhouse effect

Many readers will know that this year marks the 150^th anniversary of the publication of Darwin’s ‘On the Origin of Species’. Another breakthrough occurred in science that fateful year, this one with an Irish connection. The discovery attracted much less attention than Darwin’s theory of evolution at the time, but it has become one of the hottest topics in science today (literally).

In July 1859, the Irish physicist John Tyndall, one of the great scientists of the 19^th century, established that certain atmospheric gases absorb heat quite strongly. This innocuous-sounding discovery was established over a few short weeks, but it provided the solution to one of the great riddles of science: the famous ‘greenhouse effect’.

The greenhouse effect was first proposed by the French polymath Joseph Fourier, almost a century before Tyndall’s experiments. Fourier had wondered how the earth maintains its warm temperature, and he speculated that while heat from the sun passes easily through our atmosphere on the way to earth, heat radiated outwards by the warm earth must somehow be trapped in the atmosphere. The hypothesis was highly controversial, as it was widely assumed that gases are transparent to heat.

Tyndall, a fierce proponent of the new experimental method of science, devised a series of simple experiments to test Fourier’s hypothesis. Working in the dusty basement of the Royal Institution in London in the summer of 1859, he soon established that, while most gases are indeed transparent to light and heat, some gases – carbon dioxide and water vapour in particular – can absorb heat energy at certain wavelengths. As traces of each gas were known to exist in the earth’s atmosphere, the puzzle of the earth’s temperature was solved.

How did an Irish scientist come to make such an important discovery? John Tyndall was born in Leighlinbridge, County Carlow in 1820, the son of an RIC officer and land agent. On completing his schooling under renowned local teacher John Conwill, he started his professional career as a surveyor for the Ordinance Survey of Ireland. He was soon transferred to a position with the Ordinance Survey in Lancashire, England, but became interested in the new experimental sciences of physics and chemistry emerging in Germany. He moved to Germany in 1848 to study under the famous experimentalist Robert Bunsen at the University of Marburg, returning to England with a PhD in experimental science in 1851. By 1853, he had been appointed Professor of Natural Philosophy at the Royal Institution, a position previously held by the renowned scientist Micheal Faraday.

Tyndall remained at the Royal Institution for the rest of his career, making important discoveries in diverse areas of science, from magnetism to optics, from the physics of sound to the behaviour of bacteria. He is probably best known for ‘Tyndall scattering’, the scientific explanation for why the sky is blue. A keen mountaineer, he became interested in the science of glaciers and made several important discoveries concerning their behaviour. He became extremely well-known in Victorian England as a public communicator of science and was a prominent member of the ‘X Club’, an influential group of prominent scientists who defended evolution and other new scientific theories from religious dogma.

Tyndall’s verification of the greenhouse effect was accepted by the scientific establishment, but not regarded as a matter of vital importance. He and his colleagues were aware of the output of Victorian England’s factory chimneys, but no-one drew a link between this pollution and the greenhouse effect.

Nowadays, evidence has emerged that the average temperature of the earth and its oceans has been gradually rising since the industrial revolution. Despite many uncertainties, the scientific consensus is that this global warming is associated with an increase in carbon dioxide in the atmosphere, an increase that has been produced by human activities such as industry and transport. The discovery has led to concerted international efforts to agree on targets for reducing carbon emissions worldwide, a process that is only just beginning.

What would Tyndall make of today’s climate problems? Like most scientists of his era, he would probably find it difficult to grasp that humans could have such a global effect on nature. On the other hand, he would be greatly depressed by the shrinking of his beloved glaciers. Above all, he would be astonished to find that, of all the scientific discoveries he made, the work he did in the summer of 1859 has become a major preoccupation of 21^st century science.

Today, the work of this great Irish scientist is commemorated by the annual Tyndall lecture of the Institute of Physics, the Tyndall Centre for Climate Change Research in the UK, the Tyndall National Institute in Cork, Mount Tyndall in California and the Tyndall glacier in Chile.

Dr Cormac O’Raifeartaigh is the author of the science blog ANTIMATTER