Tag Archives: universities

Robert Boyle Summer School 2014

Last weekend saw the third Robert Boyle Summer School, an annual 3-day meeting in Lismore, Co, Waterford in honour of one of Ireland’s greatest scientists. Born in Lismore into an extremely wealthy family, Boyle  became one of the most important figures in the Scientific Revolution,  well-known for his scientific discoveries, his role in the rise of the Royal Society and his influence in promoting the role of the experiment in the ‘new philosophy’.

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The Irish-born scientist and aristocrat Robert Boyle   

 

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Lismore Castle, the birthplace of Robert Boyle

The summer school took place in the Heritage Centre in Lismore, the beautiful town that is the home of Lismore Castle where Boyle was born.  The talks covered a wide range of topics, from Boyle’s scientific legacy to the interplay of science and religion (like many figures of the scientific religion, Boyle was quite devout and extremely interested in the interface between science and religion). See here for the conference program.

This was the third such summer school, organised jointly by the CALMAST science outreach group at Waterford Institute of Technology  and the Lismore Heritage Centre. As the only such event on a major figure in the scientific revolution, it is beginning to attract some of the world’s top experts on this period of science (known as ‘early modern’). This year, the programme included talks by Lawrence Principe (Drew Professor of the Humanities at Johns Hopkins and author of The Scientific Revolution (OUP) and The Aspiring Adept: Robert Boyle and his Alchemical Quest); John Hedley Brooke (Professor Emeritus of Science and Religion and Oxford University , and author of Science and Religion: Some Historical Perspectives and Religious Values and the Rise of Science in Europe); and Terry Eagleton  (author of over forty books and Distinguished Professor of English literature at Lancaster University).

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Lawrence Principe at Boyle 2014

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John Hedley Brooke at Boyle 2014

It was the sort of conference I like best – a small number of inter-disciplinary talks aimed at curious academics and the public alike, with lots of time for questions and long breaks for discussion. On the last day, Boyle’s legacy was also celebrated by some talks concerning the science of today; we had a superb lecture on astrophysics from Professor Lorraine Hanlon of University College Dublin, and an outstanding seminar on inflammation and ageing by Professor  Luke O’ Neill, one of Ireland’s best known and most successful biochemists.  Other highlights were a lecture on fraud in modern science by Jim Malone, Emeritus Robert Boyle Professor of medical physics at Trinity College Dublin, and an open-air barbecue in Lismore Castle on Friday evening,including a re-enactment in costume of some famous Boyle experiments by Eoin Gill of WIT.

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Eoin Gill aka Robert Boyle

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Song and dance in the grounds of Lismore Castle

All in all, a superb conference in a beautiful setting.  The meeting was sponsored by Science Foundation Ireland, the Royal Society of Chemistry, the Institute of Chemisty (Ireland), the Institute of Physics (Ireland), the Robert Boyle Foundation,  i-scan, Abbott, Lismore Castle Arts and the Lismore House Hotel.

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A late night music session with Luke O’ Neill  

 

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Freeman Dyson and the Dublin Institute for Advanced Studies

On Monday, I attended the Statutory Lecture of the School of Theoretical Physics of the Dublin Institute for Advanced Studies (DIAS). This is an outreach lecture presented annually by DIAS and this year the lecture took place at University College Dublin. Better known abroad than at home, the Institute has a long and distinguished history of world-class research in fundamental areas of physics (see here), so it was entirely appropriate that the statutory lecture was given by Freeman Dyson, renowned physicist and Professor of Physics at the famous Institute for Advanced Study at Princeton, the college on which DIAS is modeled.

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Freeman Dyson at the DIAS lecture on Monday night  

The title of Freeman’s lecture was  “Are Brains Analog or Digital?” and the abstract is below:

We know that creatures like us have two separate systems for processing information, the genome and the brain. We know that the genome is digital, and we can accurately transcribe our genomes onto digital machines. We cannot transcribe our brains, and the processing of information in our brains is still a great mystery. I will be talking about real brains and real people, asking a question that will have practical consequences when we are able to answer it. I am not able to answer it now. All I can do is to examine the evidence and explain why I consider it probable that the answer will be that brains are analog.

I won’t give more details as Professor Dyson will publish his paper on the subject quite soon. Suffice it to say that tickets for the lecture sold out days in advance and there was quite a buzz on the night. Freeman held the audience spellbound, reading from his paper without the benefit of a single slide.  One could gauge the interest generated from the huge number and variety of questions afterwards. That said, I couldn’t help noticing that the Irish media took no interest whatsoever in the occasion – one wonders if a world-famous  musician or celebrity chef would be similarly ignored.

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Professor Dyson with staff from the School of Theoretical Physics at DIAS: Werner Nahm (Senior Professor and Director ), Arthur Jaffe (Professor of Mathematics at Harvard and Chairman of the board), Freeman Dyson, Vincent Cunnane (Chair of DIAS Council) and Cecil Keaveney (Registrar)

After the lecture, some of us retired to a nearby hotel where Professor Dyson and his wife regaled us with stories from his long and interesting career. Freeman was a close colleague of my late father and was instrumental in bringing Lochlainn and the rest of our family to the Institute for Advanced Study at Princeton many years ago (after this, Lochlainn returned to Ireland to take up a position at DIAS). So it was great to encounter Professor Dyson once again, this time as an adult! Not to mention that Freeman has fascinating and original views on a wide range of topics; from space travel to climate science, he remains a truly deep and original thinker.

Update

The day after the lecture, staff and friends of the Dublin Institute for Advanced Studies were treated to a private recital by the well-known Irish pianist Hugh Tinney. The connection is that Hugh’s late mother, Professor Sheila Tinney, was an accomplished mathematician who spent time at Princeton IAS and studied with Professor Dyson (Hugh himself studied maths at Trinity College Dublin before deciding on a career in music and was in the audience for Freeman’s lecture).

It was an extraordinary occasion. Hugh played beautifully and each piece was prefaced with a short discussion of the interface of mind, memory and music. The intimate setting made for one of the most exciting concerts I have experienced, far more fun than a formal venue such as the National Concert Hall. It didn’t hurt that the programme included three of my all-time favourite works, Beethoven’s ‘Moonlight’ Sonata,  Schubert’s G major Impromptu and *that* Nocturne by John Field (no.5 in B flat). The recital also had a special significance for me as it took place in the Organ Room of the Royal Irish Academy of Music, a venue I spent a great deal of time in as a young music student.

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Each piece was prefaced by a discussion of the role of mind in music

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Hugh Tinney presenting his latest CD to Professor Dyson

After the recital, we retired to dinner in a nearby restaurant. As you can imagine, one subject of conversation was the mysterious connection between maths and music. I have heard one explanation for this strange phenomenon: “People who are good at maths are good at most things!”

P.S. A video of Freeman’s lecture is now available on the DIAS website.

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Hawking, Cambridge and the infant universe

I hugely enjoyed this week’s conference ‘Cosomolgy and the Constants of Nature’  at Cambridge University. There were some truly great talks by John BarrowJohn Ellis and Thanu Padmanabhan among others, not to mention Joao Magueijo describing his famous ‘variable speed of light’ theory in person. The icing on the cake was that my visit coincided with this week’s announcement of the detection of gravitational waves from the infant universe by the American BICEP2 experiment. If correct, the signal gives very significant experimental support for the theory of cosmic inflation, as well as the phenomenon of gravitational waves predicted by general relativity…..a double whammy if ever there was one.

Yesterday, I was priviliged to attend a seminar on the new results given by George Efstathiou and Anthony Challinor, team leaders on the rival Planck experiment (EU). There’s nothing like hearing a new observation dissected by a rival group and the seminar certainly didn’t disappoint. Both Cambridge physicists concluded that the BICEP 2 result is very robust, at least at face value, with the caveat that the signal needs to be reproduced at more than one frequency. The other caveat is that although the sensitivity of BICEP2 is up to ten times that of Planck,  there is a certain tension between the BICEP2 data and last year’s published data from Planck. I was particularly interested in Professor Efstathiou’s comment that the differing data of the two experiments may be a genuine effect, i.e., may represent some new physics at wide angles (Planck) that doesn’t affect the BICEP2 (small angle) measurements . The next few months should be very interesting indeed for cosmology…(see here for a rigorous discussion of the BICEP2 data by Peter Coles).

I had my own private excitement when I was introduced to Stephen Hawking for the first time. It was a very moving encounter, Professor Hawking remembered my father and his work. Stephen was also very interested in our recent discovery of Einstein’s unpublished attempt at a steady-state model of the cosmos. Indeed, his first remark to me was that steady-state cosmic models were the dominant cosmic paradigm when he started his research career at Cambridge all those years ago. He asked me to send him a copy of Einstein’s paper and I had a stressful evening trying to do so as my college email chose that day to block me for not changing my password often enough – of all days for that to happen!

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I can’t quite believe this photo

All in all, it was yet another hugely productive visit to Cambridge University. Every time I come here something dramatic happens but I’m also looking forward to going home, I could do with a rest!

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Farewell to Clare college

Update

The American National Pubic Radio ran a piece on our Einstein discovery on today’s Morning Edition. I think it’s quite nice, apart from the usual emphasis on Einstein’s ‘blunders’ (why do journalists always see explorations as blunders?) Still, I’m learning not to be too precious about media stuff…

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Cosmology and the constants of nature at Cambridge

They say the Irish know how to party and the coincidence of yesterday’s victory in the Six Nations with a St Patrick’s weekend has brought the country to a whole new level of craziness. So it’s good to arrive in beautiful, tranquil Cambridge University for  a few day of quiet contemplation of the universe. It’s also good to get away from the hoopla generated by our recent discovery of an unpublished Einstein manuscript (see last post)…

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Clare bridge this evening

I’m here for the conference ‘Cosmology and the Constants of Nature’, the next installment in the Cambridge/Oxford collaborative research project on the philosophy of cosmology (see here for an overview of the project).  Readers with a rudimentary knowledge of cosmology or particle physics will recognize the theme of this week’s meeting. Are ‘constants of nature’ such as the speed of light in vacuum or the gravitational constant truly constant? Or did they have different values in the early universe ? Are they truly independent of one another? Or are there hidden connections we are unaware of? Where do their values come from? The programme looks truly impressive, with talks by Martin ReesJohn Barrow, John Ellis, John Webb, Pedro Ferreira, Thanu Padmanabhan and Joao Magueijo. See here for the conference programme and overview.

I’m looking forward to Joao’s talk ‘Variations of c and other constants’. Joao made headlines a few years ago when he suggested that a speed of light in vacuum in the early universe very different to today’s value could give rise to many of the effects predicted by cosmic inflation. It looked like an intriguing alternative to inflation, although I haven’t heard much about the proposal recently. Joao also wrote a really nice book on the subject – in fact, it was one of the things that inspired me to persuade my boss to allow me to teach a course on the history of 20th century cosmology. It seems a while ago now, who would have guessed my little course would lead to the discovery of an unknown Einstein model of the universe ?

Right now, it’s time to stop musing and catch up on the world with the ten o’ clock news. Except wait, I don’t have a tv! I’m back in Clare College, my favourite of all the Cambridge colleges. There’s no tv, but on the other hand there’s something about working away in an unpretentious student room overlooking the beautiful quad that I find very relaxing. A perfect place for a bit of thinking…or maybe write a murder mystery…

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Clare College – a good place for some quiet thinking

Update

Some truly great talks by , John BarrowJohn Ellis, and Martin Rees among others so far at the conference, but the big news is yesterday’s announcement  of the observation of B-mode polarization in the cosmic microwave background by the BICEP2 experiment. If correct, the signal is strong evidence of gravitational waves emanating from the inflationary epoch of the infant universe. A huge boost for the notion of cosmic inflation, not to mention strong empirical evidence for the phenomenon of gravitational waves predicted by general relativity…..a double whammy if ever there was one. I won’t say more on this as several cosmologists here at Cambridge who are team leaders on the European PLANCK experiment will give an impromptu seminar on the US results tomorrow. I’d best change my flight – every time I come to Cambridge something dramatic like this happens…

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Filed under Cosmology (general), History and philosophy of science

Einstein’s unfinished symphony in the media

Our recent discovery of an unpublished model of the cosmos by Albert Einstein (see last post or here for a preprint of our paper) is receiving a lot of media attention, it’s very humbling. First off the mark was Davide Castelvecchi with a very nice article in Nature. Davide’s article was quickly reproduced in various outlets, from Scientific American here to the Huffington Post here. Trawling over the internet, I see newspaper and magazine articles describing our discovery in a dozen languages. It’s nice to see historical material receiving this sort of attention, I guess everyone loves an Einstein story.

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I’m also intrigued that it was the traditional media that picked up the story – with the exception of Peter Woit, no-one in the blogosphere seemed to notice our preprint or even a blogpost I wrote describing our paper. Perhaps we bloggers need the imprimateur of respected print journals more than we care to admit!

I notice one slightly misleading point in the electronic version of the Nature article is getting repeated everywhere. It’s probably not quite correct to frame Einstein’s attempt at a steady-state model of the cosmos in terms of a resistance to ‘big bang’ theories; there is no reference to the problem of origins in Einstein’s manuscript. Indeed, one of the most interesting aspects of the manuscript is that it appears to have been written in early 1931, at a time when the first tentative astronomical evidence for an expanding universe was emerging but the issue of an explosive beginning for the cosmos had yet to come into focus (e.g. the great debate between Eddington and Lemaitre later in 1931). It’s interesting that the initial mention in Nature of resistance to ‘big bang’ theories  is repeated in almost all other outlets, one can’t help wondering how many science journalists read our abstract. An honorable exception here is John Farrell at Forbes Magazine. John certainly noticed the discrepancy and no wonder – John has written an excellent book on Lemaitre.

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All in all, it’s been a lot of fun so far. I’m getting quite a few emails from distinguished colleagues pointing out that Einstein’s model is trivial because it didn’t work, which is of course true. However, our view is that what Einstein is trying to do is very interesting from a philosophical point of view  – and what is even more interesting is that he apparently abandoned the project when he realised that a consistent steady-state model would require an amendment to the field equations. In short, it seems the Great Master conducted an internal debate between steady-state and evolving models of the cosmos decades before the rest of the community…

Update

There is a very nice video describing our discovery here.

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Filed under Astronomy, Cosmology (general), History and philosophy of science

Einstein’s smallest blunder

At 17.45 GMT today, I carried out the final fuel checks on our Einstein paper, took a deep breath and hit launch (okay SUBMIT).

Over the summer, I came across quite a few references to a paper Einstein wrote on cosmology in early 1931, in the wake of Hubble’s first observations of the expanding universe (Ahemperhaps you mean  in the wake of Hubble’s observation of an apparent linear relation between the recession of the spiral nebulae and their distance, an empirical result that some theorists interpreted as evidence of an expanding universe – Ed ).

Like many Einstein papers, this paper is written in German, but unlike most Einstein papers  I could not find an English translation anywhere – pretty strange, given that this is Einstein’s first official  publication in the light of the new astronomical results (and given that he wrote very few papers on cosmology). So, with permission from the Einstein Archives, I spent the summer translating the paper with a colleague and adding hysterical remarks. Sorry, historical remarks. It was a most enjoyable project, with a few surprises along the way:

(i) Einstein’s 1931 paper offers a lot of interesting insights into his thoughts on the first tentative evidence for an expanding universe, but it does not say what a lot of science historians seem to think it says

(ii) Some calculations, where Einstein estimates values for the radius of the universe and the density of matter using Hubble’s results, seem to contain a fairly obvious numerical error

(iii) The same error can be seen in writing on a blackboard preserved from a lecture Einstein gave on the paper at Oxford University in 1931

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Einstein in Oxford – nice to know we all make mistakes

There has already been quite a bit of interest in our article, it seems your humble correspondent may have gotten lucky for once. Or we  might be wrong, in which case we’re going to look very silly. In the meantime, it looks like I’ll be doing a bit of traveling this year….

Update (Jan 2014)

Our article has now been published in the European Physical Journal (History). You can find the article here or a preprint on the Physics Arxiv here.

Update (Jan 2014)

Our article made the cover of EPJ!

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Last day at COSMO13 in Cambridge

Today was the last day of the COSMO13 conference, a most enjoyable, if sometimes exhausting conference – so many seminars, not to mention a banquet in Trinity College last night.

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The conference finished this morning with lectures on dark energy from Ofer Lahav and Edmund  Copeland, on dark energy and modified gravity by Lam Hui and Claudia de Rahm, and on inflation by Richard Easther. The conference website is here and videos of the presentations will be available here in the next few days.

UPDATE: Videos of the plenary talks and pdfs of talks from the parallel sessions are  now available here.

If I had to summarize the conference in one sentence, I think the take-home message is that recent experimental results in both cosmology (from the PLANCK satellite) and particle physics (from the LHC) are strongly supportive of our basic models, giving strong confidence that our underlying theories are on the right track. The downside is that in each case, the fit is a teeny bit too good for comfort. There is a slightly worrying lack of evidence for physics beyond the standard models so far – a lack of evidence for supersymmetric particles at the LHC (although a low-mass Higgs is in principle good news for SUSY) and a lack of non-Gaussianities and parity violation in the PLANCK measurements of the cosmic microwave background. But the future is bright, especially considering the projected increases in luminosity at the LHC and the possible detection of B-mode polarization in the CMB by PLANCK.

That said, I agree heartily with Ofer Lahav’s comment that it is extraordinary to be living through a paradigm shift in cosmology, namely the discovery of the accelerated expansion (two paradigm shifts if you include inflation). Added to which we are now in an era of precision cosmology. Indeed, measurements of the cosmic microwave background by PLANCK are now reaching such a level of precision that it isn’t always meaningful to talk about agreement or tension with astrophysical measurements – the latter have quite a lot of catching up to according to George Efstathiou!

On a personal note, it’s extraordinary to see Dad’s work on supersymmetry reaching a whole new audience in cosmology, as supersymmetry breaking in the early universe  becomes a major area of research. I can’t tell you how many young researchers eyed my badge in astonishment and then started to quizz me about O’Raifeartaigh models!

Now the conference has finally ended, it’s nice to get back to work on my paper on Einstein’s cosmology in the 1930s – some of the talks here have given me some new ideas. I managed to finish most of the paper here, I’ll always think of it as my Cambridge paper!

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COSMO 2013 at Cambridge University

Today was the first day of the COSMO 2013 conference at Cambridge. Walking up the path to the hallowed Department of Applied Mathematics and  Theoretical Physics (DAMTP), I was gripped by my usual fear that I might meet with a frosty reception at the door; “No experimentalists, please!”

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The hallowed halls of DAMTP

But it’s not that sort of conference. COSMO 2013 is a very nice mix of cosmology and particle physics, theory and experiment. You can see the conference poster and programme here.

This morning started with two contrasting plenary talks on particle physics; an experimental talk by Lars Sonneschein, and a more general talk ‘From the Higgs boson to Cosmology’ by well-known CERN theoretician John Ellis.

In his talk ‘Recent Results from the LHC’, Professor Sonnenschein gave a brief overview of recent results at the LHC, from current production rates of top anti-top quarks to the famous discovery of the Higgs boson. Much of this probably wasn’t that new to the audience given the number of Higgs talks last year, but it was good to see up-to-date information on the decay modes and coupling constants for the Higgs.The main point was that with more and more accurate measurements, there is still no evidence yet of any physics beyond the Standard Model, whether one was searching for dark matter, microscopic black holes or indeed supersymmetry (SUSY). On the other hand, there were grounds for good cheer for the experimentalists given the projections Lars gave for increased luminosity at the LHC in the next few years.

John Ellis’s talk took a very different tack. He starting by explaining why a light Higgs mass and weak couplings is a good result for supersymmetry (SUSY can stabilize a light Higgs), giving theorists yet another reason to take the theory seriously, despite the ecent narrowing of windows of possibility at the LHC (at least for minimal models). Professor Ellis then made a connection with cosmology, remarking that basic Wess-Zumino SUSY models can be shown to fit very well with many generic models of inflation;in particular, adding supersymmetry to the mix can give models that fit very comfortably within the recent PLANCK results (some fall well within the dark blue region in the famous Planck figure below). A colleague of a certain age commented to me afterwards  that he isn’t quite reconciled  with the way inflation has become the dominant paradigm in today’s cosmology; for my part, I can never get used to today’s discussions of  supersymmetry in both cosmology and particle physics, having grown up thinking of it as an obscure theory practised only by my father and a few colleagues around the world! Science truly evolves…

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Prof Ellis wearing his Standard Model t-shirt

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Generic SUSY versions of inflation can give models that fall within the most probable region (dark blue)

At question time afterwards, I commented that I was struck by the contrast between the two talks, i.e. the strong motivation for SUSY from theory but the lack of results so far at the LHC, and asked Professor Ellis whether he thought the first evidence for SUSY might indeed come from the cosmic microwave background rather than particle accelerators (I made a mess of the question, nervous for once!). He responded by pointing out that it took 40 years to find the Higgs in particle accelerators, thus we should not be too impatient.  This answer makes a lot of sense to me, I’m a bit dismayed at the way SUSY scepticism has quickly become almost as popular a sport as string theory scepticism. After all, theory is often decades ahead of experiment, particularly in particle physics…

There were two other plenary lectures after coffee, an overview of Dark Matter by Malcolm Fairbairn and a talk on neutrino masses by Silvia Pascoli. They were both excellent talks but there is so much going on I just can’t keep up! Also, Stephen Hawking is sitting three tables away, also working away at a computer – I’m going to tidy myself off to the afternoon sessions before someone mistakes me for a journalist and chases me out of the canteen!

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Summer hols; summer school, swimming and that book

You must be finished for the summer? Like most academics, I get asked this question every day in summer, usually by village acquaintances convinced that college closes the day the students finish their exams.

Some lecturers in the Institutes of Technology do indeed take off from June 20th to September 1st; that is their right, given the heavy teaching load during termtime. However, for those of us who try to keep up the research, the summer months are the time to get something done, just like our colleagues in the universities.

For me, this is no chore  – the sheer bliss of being able to do quiet research without classes, meetings, staff interactions and all the rest of it. Very restful. Also, we’re having a serious heatwave in Ireland this month and I’m happy to escape to the cool, quiet office every day. So I plug away happily during the day and treat myself to a swim in my village in the evenings..

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Tide’s in on Lawlor’s Strand in Dunmore East

Actually, I did give some ‘cameo’ lectures this week and last, to our summer school. We have a very nice bunch of engineering, computing and business students visiting from Kiel in Germany, and I had fun trying to condense my climate science course down to a one-hour presentation for each group. I haven’t given short presentations on climate before, it was very satisfying to prepare (see here for a copy of the talk)  The other thing I noticed was that students from the continent always seem to be very mature, polite and interested. I must look into an exchange sometime, do they have Erasmus for staff?

My main task this summer is to finish my little book on cosmology. It’s based on a course I have taught for some years and it’s been a lot of fun to write. Now I’m finding that it’s one thing to write a book and quite another to get it published! Still, I have plenty of time now to be writing book proposals and writing to publishers. In the meantime, I look forward to a swim in the sea everyday after work and a walk into the village. It’s funny to live in a village where others come for summer holidays!

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Tide’s out on Lawlor’s Strand in Dunmore East

Update

Unfortunately it’s so warm, we’re beginning to get quite a few jellyfish. Hope it cools down a little next week!

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Last day of Quantum Foundations conference at Oxford

Yesterday was the last day of the  Cosmology and Quantum Foundations  conference, a symposium that formed part of the  Establishing the Philosophy of Cosmology project at Cambridge and Oxford.

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There was no workshop in the  morning, but there were two weighty lectures in the afternoon, ‘Inflationary Cosmology as a Laboratory for Primordial Quantum Mechanics’ by Antony Valentini and ‘Relational Quantum Mechanics: Spinfoam Cosmology’  by Carlo Rovelli.

Antony Valentini’s talk was the second installment of his thesis that we should consider the possibility that the quantum equilibrium universe we experience is simply a subset of a much larger ensemble which is deterministic, not in equilibrium, and does not obey the standard rules of quantum probability. In this model, elements of the larger ensemble made a transition  by a process of relaxation on atomic timescales to the quantum equilibrium we see today. Antony hypothesized that observational cosmology might offer a test for his model because any non-equilibrium states remaining before cosmic inflation would have become frozen during this period,  feeding into the cosmic microwave background at the end of inflation. His analysis suggested one explanation for the well-known power deficit in the CMB at long wavelengths in the Planck and WMAP data.  I have no idea what the theoreticians thought of Antony’s hypothesis, but talks like this certainly give the lie to those who accuse physicists of groupthink and of being incapable of thinking outside the box!

Carlo Rovelli then gave the second installment of his talk on his relational view of quantum mechanics (see last post). The main point here was that adding gravity to the analysis is not a complication in the case of the relational interpretation of qt because the model is fundamentally relativistic in nature (gravity is simply a curvature of spacetime in relativity). He went on to describe how the theory leads to the ‘quantum loop’ view of quantum gravity. I am not qualified to comment on the theory, but what I took out of Carlo’s talks is that the only fundamental entities in relational theory are covariant quantum fields -the wavefunction has no physical significance, any more than a mathematical operator.

All this was followed by a round table discussion between, Carlo, Antony, Simon Saunders and David Wallace. For many of us, this was a major highlight of the conference. It was a privilege to hear major proponents of the many-worlds interpretation of quantum theory (Saunders and Wallace) arguing point-by point against the relational view (Rovelli), not to mention pointed interjections from heavyweights in the audience such as John Barrow, Julian Barbour and Joe Silk. During the course of the debate, it struck me that the discussion was in some ways a modern echo of the classic debate between the Heisenberg and Schroedinger interpretations of the quantum world. I could almost see Heisenberg behind Carlo Rovelli’s chair, applauding his emphasis on the discreteness as the key property of the quantum world and his dislike of the wavefunction. In the opposite corner, Schroedinger’s view had much in common with the many-worlds camp because of his dislike of collapsing wavefunctions. Indeed, it has recently been suggested by several authors that Schroedinger’ s later work on quantum interpretation somewhat anticipates the many-worlds view (will dig out references on this).

So a splendid finish to a splendid conference; an important debate on the meaning of quantum theory between leading proponents of alternate modern interpretations of the theory, with echoes of history throughout.

Update

It all happens at Oxford. Strolling past the Sheldonian this evening, I heard the familiar strains of Vivaldi’s Four Seasons. Turns out Nigel Kennedy was giving a concert with the Oxford Philomusica, so I sneaked into the foyer to hear the last few movements. You don’t hear much about Kennedy since he moved to Poland, but his performance was as electric as ever. I timed the applause at over 20 minutes, he certainly hasn’t lost his gift for communicating with the audience. However, the real surprise was the orchestra, it didn’t sound like any college orchestra to me – lovely crisp playing, fantastic articulation in the fast passages, and super pianissimos in the slow passages. Turns out the Oxford Philomusica is a relatively new initiative, a professional orchestra in residence at the university. What a great idea , I’m sure it gives a unique opportunity for the very best of the music students

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Nigel Kennedy at the Sheldonian

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Filed under Cosmology (general), quantum theory