I was making a start at cleaning out some of the stuff in my office yesterday and came across a bunch of foreign editions of my book Cosmology: A Very Short Introduction. I’d forgotten I had these, and am not even certain what languages they are all in. Is the first in Japanese or Korean? I really can’t remember.
…still, it’s interesting to see how they’ve chosen different covers for the different translations, and at least I know what my name looks like in Russian Bulgarian!
I’m having a restful morning at home because (a) it was our Departmental Christmas Lunch yesterday meaning that I’m feeling a bit fragile and (b) there’s a planned electrical shutdown in our building this morning meaning that there’s not much point going in until it’s all back up anyway.
Anyway, since various people made the odd facetious comment accusing me of skiving off last week, I thought I’d take the opportunity to reflect a little on the Winter School that I was lecturing at last week. This took place at Passo del Tonale, in the Italian Alps and was the Sixth in a series of schools for graduate students and postdocs held there annually. When I was invited to take part, I was asked to give five lectures as a sort of overview of the current state of cosmology. Subsequently one of the other speakers dropped out so instead of inviting a replacement, the remaining four were given an extra lecture each. Then one of those was taken ill during the summer school so I stepped in at short notice to give another one. And so it came to pass that I gave seven lectures altogether, in the space of five days. That’s considerably more lecturing than I would have done had I stayed in Cardiff.
Anyway, here’s a picture of me during one of the lectures (taken by one of the participants, Chris Crowe).
Afternoons were kept free for skiing and snowboarding, but my dodgy knees don’t allow me to participate in such activities. I am not shap’d for sportive tricks nor made to court an amorous looking-glass. I had lectures to prepare anyway.
However the hosts looked after us well and there was a fine conference dinner on Wednesday evening,
the main course featuring a roast pig brought into the room by the chefs with some aplomb:
Everything was eaten. I was given the honour of having one of the ears, in fact. A bit chewy, but quite tasty in case you were wondering. I don’t know what the vegetarians did.
Anyway, at the end of the school the lecturers were presented with bottles of fine Grappa. I’ll no doubt be sampling mine over the Christmas vacation!
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In an earlier post, I mentioned an upcoming conference in Arizona to celebrate the pioneering work of the American astronomer Vesto Slipher. As mentioned previously, 2012 marks the centenary of Slipher's observation that light from the Andromeda nebula was Doppler shifted, a finding he interpreted as evidence of a radial velocity for the nebula. By 1917, he had established that the light from many of the distant nebulae is…
Not having much time to write anything particularly original, I thought I’d use this blog to advertise a forthcoming centenary celebration which I hope to attend and speak at, if my recovery goes to plan. The text below is taken from the conference website for a meeting due to take place at the Lowell Observatory in Flagstaff, Arizona from September 13-15. I’m sure they won’t mind me borrowing it, as it helps promote the event. Registration is open until 10th August…
On September 17, 1912, Vesto Slipher obtained the first radial velocity of a “spiral nebula” – the Andromeda Galaxy. Using the 24-inch telescope at Lowell Observatory, he followed up with more Doppler shifts, and wrote a series of papers establishing that large velocities, usually in recession, are a general property of the spiral nebulae. Those early redshifts were recognized as remarkable by Slipher, and were critical to the discovery of what came eventually to be called the expanding Universe. Surprisingly, Slipher’s role in the story remains almost unknown to much of the astronomical community.
The nature, and especially the distance, of spiral nebulae was fiercely argued – most famously in the 1920 Shapley-Curtis debate. Hubble’s 1923 discovery of Cepheids in Andromeda, along with Henrietta Leavitt’s period-luminosity relation for Cepheids, led to a distance scale for the nebulae, enabling Lemaitre (1927) to derive a linear relation between velocity and distance (including a “Hubble constant” and, by 1931, a Primeval Atom theory).
Meanwhile, a new concept of space and time was formulated by Einstein, providing a new language in which to understand the large-scale Universe. By 1932, all the major actors had arrived on stage, and Universal expansion – the most general property of the Universe yet found – acquired a solid basis in observation and in the (relativistic) concept of space. “Space expands”… or does it? How did Lemaitre and Hubble interpret this concept? How do we interpret it? It continues to evolve today, with cosmic inflation and dark energy presenting new challenges still not fully assimilated.
This conference is in honor of Vesto Melvin Slipher and is timed to coincide with the 100th anniversary of the first measured Doppler shift in a Galaxy (then known as a Spiral-Nebula) on September 17, 1912:Slipher 1913 Lowell Obs 2, 56
We are bringing together astronomers and historians of science to explore the beginnings and trajectories of the subject, at the place where it began.
Follow @telescoperHaving had a bit of fun recently at Ant Whitworth’s expense, I think it’s only fair I should let you have a go at me. Here’s a picture of me taken at a book signing a while ago….
Please feel free to suggest a caption through the comments box…
Follow @telescoperWell, here I am back in Cardiff after my little trip to Merseyside. The weather behaved itself and so did the trains in both directions, so it was quite a pleasant travelling experience. In fact, going there yesterday I managed to make a technically impossible connection at Crewe, owing to the train from Cardiff being a minute or two early and the train to Liverpool being a minute late.
I stayed last night at the Jury’s Inn at Albert Dock, shown on the left here. There’s a sort of Ferris Wheel thing next to it. These contraptions seem to be popping up all over the place. Next thing you know there’ll be one in London! The hotel was of its type, generic but reasonably comfortable. Brings back memories of STFC panel meeting; the Jury’s Inn there is a standard place to stay in Swindon when sentenced to hard labour. Unfortunately the one I stayed in was booked up by multiple stag and hen parties and was ridiculously noisy all night. I didn’t really get any sleep until well after 4am. Grump.
Anyway, last night we had a very nice dinner at the Clove Hitch restaurant/bistro (which I definitely recommend) preceded by a pint at the famous Philharmonic Pub. Thanks to Phil and Sue for looking after us so nicely.
My talk opened the proceedings at the Merseyside Astronomy Day, which was held at Spaceport on the Birkenhead side of the Mersey. Here’s a view of Liverpool’s impressive skyline taken from there, with a nice sailing barge on the Mersey.
The small auditorium – usually used for Planetarium shows – was pretty full and I think my talk went quite well, although it’s not really for me to say. They did actually record everything so if I can get hold of a copy I might post it. Anyway, after my turn there was a fascinating lecture by Prof. Peter Read of Oxford University about the atmospheres of Jupiter and Saturn.
After a quick lunch we used Liverpool’s excellent public transport to zip back to Liverpool Lime Street and I had a relaxing and punctual journey back to Cardiff, albeit with no miracle change at Crewe this time. Dozing on the train I quite startled to wake up near Shrewsbury to find a vintage steam locomotive in sight:
No doubt there’ll be someone out there in internetshire who will tell me all about this train through the comments box but for now I’m going to make some dinner and take it easy as I’m rather knackered.
Follow @telescoperI’m just about to head by train off up to Merseyside (which, for those of you unfamiliar with the facts of British geography, is in the Midlands). The reason for this trip is that I’m due to give a talk tomorrow morning (Saturday 12th May) at Merseyside Astronomy Day, the 7th such event. It promises to be a MAD occasion.
My lecture, entitled The Cosmic Web, is an updated version of a talk I’ve given a number of times now; it will focus on the large scale structure of the Universe and the ideas that physicists are weaving together to explain how it came to be the way it is. Over the last few decades astronomers have revealed that our cosmos is not only vast in scale – at least 14 billion light years in radius – but also exceedingly complex, with galaxies and clusters of galaxies linked together in immense chains and sheets, surrounding giant voids of empty space. Cosmologists have developed theoretical explanations for its origin that involve such exotic concepts as ‘dark matter’ and ‘cosmic inflation’, producing a cosmic web of ideas that is in some ways as rich and fascinating as the Universe itself.
Anyway, I’m travelling to Liverpool this afternoon so I can meet the organizers for dinner this evening and stay overnight because there won’t be time to get there by train from Cardiff tomorrow morning. It’s not all that far from Cardiff to Liverpool as the crow flies, but unfortunately I’m not going by crow by train. I am nevertheless looking forward to seeing the venue, Spaceport, which I’ve never seen before.
If perchance any readers of this blog are planning to attend MAD VII please feel free to say hello. No doubt you will also tell me off for referring to Liverpool as the Midlands…
Follow @telescoperA while ago I blogged about an event I attended, called Experimental Marathon, which was held in Reykjavik Art Museum in May 2008. I was reminded about this for various reasons recently and managed to dig up a couple of pictures of my presentation, which appeared in the glossy book of the event that was produced later on.
As you can probably infer, I gave a talk which was basically about the cosmic microwave background. My “experiment” was a television set that wasn’t tuned properly producing a screenful of static. I pointed out that some (actually not that much) of the buzz was coming from the beginning of the universe. Pretty unoriginal and gimmicky, I know, but it seemed to go down quite well with the audience and I had some nice questions and comments at the end of my 20 minutes.
During the three days of the event I also got to meet quite a few artists, scientists and other luminaries whose names are on the list here.:
You can find one of the numerous reviews of this event here, which also includes quite a few pictures of various experiments including one that some might consider to be NSFW …
Follow @telescoperI was having a chat over coffee yesterday with some members of the Mathematics Department here at the University of Cape Town, one of whom happens to be an expert at Bridge, actually representing South Africa in international competitions. That’s a much higher level than I could ever aspire to so I was a bit nervous about mentioning my interest in the game, but in the end I explained that I have in the past used Bridge (and other card games) to describe how Bayesian probability works; see this rather lengthy post for more details. The point is that as cards are played, one’s calculation of the probabilities of where the important cards lie changes in the light of information revealed. It makes much more sense to play Bridge according to a Bayesian interpretation, in which probability represents one’s state of knowledge, rather than what would happen over an ensemble of “random” realisations.
This particular topic – and Bayesian inference in general – is also discussed in my book From Cosmos to Chaos (which is, incidentally, now available in paperback). On my arrival in Cape Town I gave a copy of this book to my genial host, George Ellis, and our discussion of Bridge prompted him to say that he thought I had missed a trick in the book by not mentioning the connections between Bayesian probability and neuroscience. I hadn’t written about this because I didn’t know anything about it, so George happily enlightened me by sending a few review articles, such as this:
I can’t post it all, for fear of copyright infringement, but you get the idea. Here’s another one:
And another…
Nature Reviews Neuroscience 11, 605 (August 2010) | doi:10.1038/nrn2787-c1
A neurocentric approach to Bayesian inference Christopher D. Fiorillo
Abstract A primary function of the brain is to infer the state of the world in order to determine which motor behaviours will best promote adaptive fitness. Bayesian probability theory formally describes how rational inferences ought to be made, and it has been used with great success in recent years to explain a range of perceptual and sensorimotor phenomena.
As a non-expert in neuroscience, I find these very interesting. I’ve long been convinced that from the point of view of formal reasoning, the Bayesian approach to probability is the only way that makes sense, but until reading these I’ve not been aware that there was serious work being done on the possibility that it also describes how the brain works in situations where there is insufficient information to be sure what is the correct approach. Except, of course, for players of Bridge who know it very well.
There’s just a chance that I may have readers out there who know more about this Bayes-Brain connection. If so, please enlighten me further through the comments box!
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