Atoms of light: Book launch at UCD

I drove up to Dublin yesterday evening for a book launch at University College Dublin. Two of my former professors, Alex Montwill (who taught courses in formal quantum theory and particle physics) and Ann Breslin (special relativity and experimental high-energy physics) have just written a popular science book ‘Let there be light: The Story of Light from Atoms to Galaxies‘ published by Imperial College Press. Both were among the best teachers I ever had, as well as outstanding researchers in the field of particle physics. In fact, Alex was Ireland’s foremost experimental particle physicist for many years, but is probably best known for a series of lectures on modern physics on national radio.

I’ve never been to a physics book launch before, it was great fun. All the great and the good from the world of Irish physics were there, including just about everyone who taught me as an undergraduate! Talk about a trip down memory lane. One big difference – I couldn’t believe how beautiful Belfield campus is now with tons of landscape gardening and new buildings.

The book was launched with great aplomb by Dick Ahlstrom, science editor of The Irish Times. Dick has played a huge role in the communication of science to the public in Ireland, mainly through writing and editing a full page on science every week in The Irish Times (you can see an example here). As far as I know, there is a fairly unique example of a full page on science in a quality newspaper, and is now an integral part of that great paper.

I have yet to have a good read of the book but it looks superb, as you might expect of the culmination of a lifetime’s reflection on physics by two highly respected physicists and teachers. The book is pitched at a level slightly above most popular science books, somewhere between undergraduate and the layman, and is an introduction to pretty much all of modern physics from the perspective of the study of the nature of light – from optics to wave theory, from astronomy to quantum theory, from electromagnetism to special relativity. An unusual feature is the essay-like style of the presentation – you can start reading anywhere (though it’s hard to put down). Another unique feature are the illustrations; a huge number of really helpful small illustrations, from well-known images to sketches and cartoons. A lot of the concepts are illustrated via an owl character, which reminds me of the books of George Gamow, an old hero of mine.

If you want to know more, buy the book. I’m looking forward to reading it at the weekend

Update: You can get it at discount at the World Scientific site, and there is a very nice overview of the book there

Standard Model at Trinity College

I gave an introductory talk on the Standard Model and the forthcoming LHC experiments to some physics students in Trinity College last night. There wasn’t a huge turnout, but it was great being back in the Schroedinger Theatre – lovely wooden theatre, steep tiered seating, buckets of atmosphere. All mod cons of course but also a good big old fashioned blackboard for back-of-the-envelope calculations to accompany the slides (you can get the slides here).

It was a real trip down memory lane – as a postgrad, I used to give quantum mechanics tutorials in the same theatre to 2nd year theoretical physics. I used to spend hours preparing answers to Denis Weaire’s problem sheets, only to find the students hadn’t opened a book!

Anyway, I think the lecture went well (I heard it was completely incomprehensible  – Ed). The best thing about it was the poster – students really know how to put a poster together.

glendagilson1

I also found time to point out that Ireland is not a member of CERN, almost uniquely in western Europe (see September posts on this). This denies our best students and researchers the opportunity to work with world-class researchers at a world-class facility – an omission that has had a devasting effect on experimental particle physics in Ireland. The map below says it all really.

The 20 member states of CERN (blue) do not include Ireland. Many non-European States have associate membership (U.S., China, India and Japan), but this does not include Ireland either.

Steady state theory back

I’m up to my tonsils in teaching this week, so no time for a proper post. However, over at Cosmic Variance there is a very interesting discussion of a recent paper by Geoffrey Burbridge on the Arkiv ;

A Realistic Cosmological Model Based on Observations and Some Theory Developed Over the Last 90 Years

Essentially, the author is defending the steady-state model of the universe (yes, he’s a member of the original Hoyle group). I wasn’t aware that anyone was still pushing this alternative to the Big Bang, I thought everyone had accepted the evidence was overwhelming. Sean Carroll has a very nice discussion of this point, i.e. the difficulty of ever settling a scientific dabate to everyone’s satisfaction. Every reader of this blog should read it carefully.

P.S. The basic idea of the steady-state model is that matter is continuously created – most physicists consider it effectively ruled out by the simple fact that our universe is clearly different now from what it was in the past. Not to mention the small matter of the cosmic microwave background, a clear fossil of the Big Bang

Zeilinger in Ireland

The highlight of Science Week (see below) was a talk on Monday evening at University College Cork by Anton Zeilinger, the world’s foremost quantum experimentalist. The title of the talk was ‘Quantum puzzles and their applications in future information technologies’ and it was sponsored by Science Foundation Ireland, the Institute of Physics and the Tyndall Institute. (The connection is that Sile Nic Chormaic, the leader of the quantum optics group at the Tyndall Institute, is a former member of the Z. group).

Zeiinger started with a brief introduction to quantum theory, from Planck’s quantum of action to the emergence of wave theory. He then focused on the problem of interpretation, starting with Bohr’s double slit experiment. Having explained the ideas of interference and entanglement, the theme of the talk was set at at the difference between Bohr’s spooky-action at a distance and Einsein’s refusal to yield either locality or realism. Z. then gave a clear depiction of Bell’s theorem and described how the experiments of his own group effectively ruled out hidden variable theory, leaving the question of whether locality or realism was violated. He also mentioned recent tests his group have done that point at the latter, you can read a good account of them here.

Quantum interference on the ski slope

In the second part of the talk, Z. gave a masterly overview of the applications of entanglement – teleportation, encryption and quantum computing - and described the astonishing progress of his group on each. Funding agencies should note how experiments concerning the esoteric question of the interpretation of quantum physics turned out to have important practical applications.

Interestingly, Zeilinger returned to the nature of reality in the final part of the talk. After a careful discussion of recent experiments, he discussed the modern philosophy that it is operationally impossible to seprarate reality and information in any meaningful way, finishing with his own view – that information, not reality, is the fundamental aspect of our lives.

At question time, the speaker was as affable as ever. In response to a question from me on the so-called BB problem (who/what was there to observe it), he pointed out that qt does not specify the ordering of space-time – i.e. it doesn’t matter when the observable is observed…

All in all, this was a fabulous talk on cutting edge quantum research and its applications.

The Zeilinger record: entangled photons over the Canary Islands

P.S. Zeilinger has a well-known blog here, but you’ll need to brush up on your German!

P.P.S. There is a super description of the Einstein-Bohr debate and the Zeilinger experiments here, see comment by Zeynel

Science week, Walton and the LHC

This week is Science Week in Ireland, a week of events designed to get schoolchildren and adults interested in the world of science. There are all sort of events, lectures and activities are going on all over the country – you can see a list on the website. Here in the southeast, CALMAST, the WIT Center for the Advancement of Learning of Maths, Science, and Technology, are doing their usual super job, with exhibitions, science shows and lectures…see the program above.

My own contribution was a lecture on the LHC for secondary schools this morning (you can see the slides here). I’m giving a similar lecture to the public in the neighbouring town of Dungarvan tomorrow evening , with one crucial difference. Dungarvan is the birthplace of Ernest Walton – as in Cockcroft-Walton, the team that built the world’s first successful particle accelerator and used it to split the atomic nucleus. Their accelerator was the precursor modern accelerators and is still used as a pre-amp today (I’m told there is a mock up of the original somewhere in CERN, must check this). Anyway, I intend pitching this particular LHC lecture as Walton’s legacy.

The Cockroft-Walton experiment  was a spectacular success, given that the energy they used was relatively low. Not only did it offer a nice verification of E = mc2, it was also a convincing demonstration of quantum tunelling – George Gamow had visited the Cavendish a few months earlier, and convinced Rutherford that they might succeed at low energy. There is a nice description of this story in the book ‘The Fly in the Cathedral’ by Brian Cathcart.

Ernest Walton: Ireland’s only Nobel in physics

In between these two lectures, I’m driving to Cork to catch the highlight of the week – Anton Zeilinger is giving a talk on quantum entanglement and its applications…wow. More on this tomorrow.

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The best surfspot in the world

This week I’m back hard at work after a short break with The Surf Experience in Lagos, Portugal. It was certainly worth taking a few days out, staying in a beautiful big house in the Algarve with about 20 other guests. Each day we went to the beach in a convoy of jeeps, west or south coast depending on the wave conditions.

Arrifana beach on the west coast

As usual, the camp was full of Germans – my favourite people to go on holiday with, and a great opportunity to improve my German. There was a lovely atmosphere in the house every evening, as the guests dined together and shared a few beers before collapsing into bed. Defnitely my favourite surfspot in the world.

Surfcamp in Lagos

I got plenty of work done too – I read a chapter of Manjit Kumar’s book on quantum physics every night, as I have been asked to review it for Physics World, the flagship magazine of the Institute of Physics. Today, it’s back to the real world, as I take our third years for a course in the quantum theory of solids.

On the plane home, I had a great thought for their first lecture. I think I’ll do some revision by getting the class to derive de Broglie’s relation from relativity, and to show how it led Schrodinger to his wave equation (they’ve already had a course in qt). It’s a nice starting point for solid state physics, and I had great fun going through the derivations on a napkin on the plane home (ok, they’re not really derivations but such outlines give students a great feel for the quantum world) – really nice physics.

Next week is Science Week in Ireland, and I’m giving several talks on the LHC, so I’m knee deep in that preparation too…sigh. I miss Lagos.