Archive for University of Sussex

Hic Sunt Leones

Posted in The Universe and Stuff with tags , , , , , , on November 15, 2017 by telescoper

Just time for a very quick post, as today I travelled to Brighton to attend an inaugural lecture by Professor Antonella De Santo at the University of Sussex.

Antonella was the first female Professor of Physics at the University of Sussex and I’m glad to say she was promoted to a Chair during my watch as Head of the School of Mathematical and Physical Sciences, at Sussex. That was about four years ago, so it has taken a while to arrange her inaugural lecture, but it was worth the wait to be able to celebrate Antonella’s many achievements.

The lecture was about the search for physics beyond the standard model using the ATLAS experiment at the Large Hadron Collider, with a focus on supersymmetry and possibly candidates for dark matter. It was a very nice lecture that told a complex story through pictures and avoiding any difficult mathematics, followed by a drinks reception during which I got to have a gossip with some former colleagues.

The title, by the way, stems from the practice among mediaeval cartographers of marking terra incognita with `Here be lions’ or `Here be dragons‘. I hasten to add that no lions were harmed during the talk.

Anyway, it was nice to have an excuse to visit Brighton again. The last time I was here was over a year ago. It was nice to see some familiar faces, especially in the inestimable Miss Lemon, with whom I enjoyed a very nice curry after the talk!

Now for a sleep and the long journey back to Cardiff tomorrow morning!

Advertisements

R.I.P Leon Mestel (1927-2017)

Posted in Biographical with tags , , on September 18, 2017 by telescoper

Leon Mestel FRS, photographed by Lucinda Douglas-Menzies

I heard this weekend the very sad news that on Friday 15th September 2017, we lost one of our great astrophysicists. Professor Leon Mestel FRS, pictured abvove, passsed away, peacefully in his sleep, at Addenbrooke’s Hospital. He was 90 years old.

Leon Mestel was a scientist of the highest distinction. Elected a Fellow of the Royal Society in 1977, his research interests were very broad, encompassing, but not restricted to, the areas of star formation and structure, especially stellar magnetism and astrophysical magnetohydrodynamics. Among his contributions in other areas were important papers on gravitational collapse and equilibrium in the context of galaxy dynamics, of which the classic `Mestel Disk’ is just one example. He has been awarded both the Eddington Medal (1993) and the Gold Medal (2002) of the Royal Astronomical Society. He had great physical insight which was backed up with prodigious mathematical skill and an encyclopedic knowledge of astrophysics. He also had great powers of concentration and the determination to tackle the kind of extremely challenging problems that scared off lesser intellects. Leon  was an ‘old school’ theoretical astrophysicist who was held in very high regard across the astrophysics community, and he will be greatly missed.

Others more expert than me will be able to pay proper tribute to his scientific work, so I’ll restrict myself here to a few personal reminiscences.

Leon Mestel was Professor in the Astronomy Centre at the University of Sussex when I joined it to start my DPhil in 1985. We new postgraduate research research students were required to take four courses on various aspects of astronomy, and pass oral examinations on them, before being allowed to progress beyond the first year. One of these courses was a course on Stellar Structure, taught by Leon Mestel. His lectures were pretty intense – and, I have to say, not made any easier to understand by his truly terrible handwriting on the blackboard! – but I learned a huge amount from them. I still have the lecture notes I took, in fact.

I had a root around in my old files this morning and found this evidence that I once knew something about stars!


All of us found Leon very scary to start with. He was intellectually quite intimidating and seemed to be a rather fierce and irascible character. That opinion changed when, a few weeks into term, he invited us to his house in Lewes for a social evening. We were all a bit nervous on the way there, unsure of what to expect, but as it turns out Leon was a marvellously entertaining and avuncular host. He had a wicked sense of humour and a seemingly inexhaustible stream of jokes, across a spectrum from groan-worthy puns to very risqué stories, including a  liberal measure of archetypal Jewish humour.  Leon’s father was a Rabbi, actually.  That evening broke the ice and we all realised that the was one of the good guys. That he came across as grumpy sometimes was because he was concentrating very hard, but it was rather easy to make him laugh and bring that twinkle to his eye that we will all remember.

His sharp brain and very broad knowledge meant that Leon could spot bullshit at a  considerable distance and, while he often seemed to be snoozing through  our weekly seminar,  he invariably woke up at the end and asked a penetrating question. Since one of his main interests was the role of magnetic fields in astrophysics, a subject that sends many astrophysicists screaming from the room, he would often choose something about magnetism as a question. When I was there his main focus was on the fiendishly difficult problem of building a self-consistent model of the pulsar magnetosphere. He was, however, genuinely interested in all branches of astrophysics and always recognised good work when he saw it, especially from younger scientists.

During my time as a PhD student I had some problems that required me to take quite a lot of time off. Leon was extremely kind and supportive during this period, and he even bent the rules a bit to avoid putting me through the formal process of interrupting my studies. When I was back at work and just about finishing my thesis in 1988 it was Leon who came to see me in person, with a big smile on his face, and offered me a postdoctoral position at Sussex to follow my graduate studies. I nearly fell off my chair with surprise and gratitude.

After I joined the staff later in 1988, it became a bit of a ritual for us to visit the Senior Common Room (which was situated in what is now Bramber House) for lunch, followed by coffee. It turned out that Leon liked to do the Times crossword with his post-lunch coffee. He wasn’t at all averse to a collaborative effort on tricky research problems, and it was thus with crosswords too. We both preferred the Guardian puzzle, actually, but he saved that one for after work and did the Times one because the paper was provided free in the SCR. There was also a Chambers dictionary.

I left Sussex in 1990 and Leon retired in 1992. I didn’t see as much of him after that, except for the occasion when he and my former DPhil supervisor John Barrow organized a meeting in 2004 about Eddington at which I was honoured to be asked to give a talk about the 1919 eclipse expeditions. That was a very nice occasion at which Leon was in sparkling form. Thereafter I saw him occasionally at the RAS Club, but in recent years he didn’t come so often as he found it increasingly difficult to get around.

Leon Mestel was not only a great astrophysicist but also a great character.  I’m so very sorry I can’t attend his funeral (which is being held tomorrow), but I send heartfelt condolences to his family, friends and colleagues.

Rest in Peace Leon Mestel FRS (1917-2017)

 

A Blueprint for a Quantum Computer

Posted in The Universe and Stuff with tags , , , , on February 16, 2017 by telescoper

I’m a little bit late blogging about this topic, as it relates to a paper published on 1st February 2017, but it’s a pleasure to be able to draw your attention to an important paper by a group led by a former colleague of mine from the University of Sussex, Prof. Winfried Hensinger, known to his friends as “Winni”. In essence they have constructed a practical way to build a working quantum computer.

Here is the abstract of the latest paper which explains the significance of the work:

The availability of a universal quantum computer may have a fundamental impact on a vast number of research fields and on society as a whole. An increasingly large scientific and industrial community is working toward the realization of such a device. An arbitrarily large quantum computer may best be constructed using a modular approach. We present a blueprint for a trapped ion–based scalable quantum computer module, making it possible to create a scalable quantum computer architecture based on long-wavelength radiation quantum gates. The modules control all operations as stand-alone units, are constructed using silicon microfabrication techniques, and are within reach of current technology. To perform the required quantum computations, the modules make use of long-wavelength radiation–based quantum gate technology. To scale this microwave quantum computer architecture to a large size, we present a fully scalable design that makes use of ion transport between different modules, thereby allowing arbitrarily many modules to be connected to construct a large-scale device. A high error–threshold surface error correction code can be implemented in the proposed architecture to execute fault-tolerant operations. With appropriate adjustments, the proposed modules are also suitable for alternative trapped ion quantum computer architectures, such as schemes using photonic interconnects.

Here’s a short video explaining the setup

This result has generated a lot of good publicity for the group at Sussex, including a piece in the Financial Times and a personal appearance by Winni himself on Sky News.

It’s great to see the  Ion Quantum Technology group continuing to do really well and I’m sure the investments made in physics research at the University of Sussex over the last few years will bring even more exciting developments in the near future!

 

A New Head for the Old School

Posted in Biographical, Education with tags , , on December 13, 2016 by telescoper

Just a brief post to pass on the news (which I just heard this morning) that the University of Sussex has now formally announced that Professor Philip Harris will be taking over as Head of the School of Mathematical and Physical Sciences at the University of Sussex, the position I held until this summer.

I worked a lot with Philip during the time I was at Sussex as he was Head of the Department of Physics & Astronomy for part of that period. I’m sure he’ll do a great job and I wish him – and indeed the whole School – all the very best for the future!

Incidentally, the news item announcing Philip’s appointment contains the following snippet:

Both departments are ranked first in the UK for graduate prospects in the Times and Sunday Times University Guide 2017 (Destinations of Leavers from Higher Education Survey, 2015-16), with 100% of Mathematics BSc students being in work or further study within six months.

I wasn’t aware of this interesting news before today, and I’m sure it will provide a boost to the School’s efforts in the currently rather challenging student recruitment market. Of course Philip Harris can now take credit for anything good that happens to the School, whereas if anything goes wrong he can always blame it on the old Head of School!

 

Three Cheers for Three Chairs!

Posted in Uncategorized with tags , , , on November 2, 2016 by telescoper

Just a quick post to say public congratulations to three of my former colleagues in the Department of Physics and Astronomy at the University of Sussex.

My spies tell me that the following have recently been promoted to Professorial positions:

  • Kathy Romer (now Professor of Astrophysics) – Kathy is principal investigator of the XMM Cluster Survey collaboration and is coordinating cluster research for the Dark Energy Survey project.
  • Antony Lewis (now Professor of Cosmology) – Antony works on theoretical models of the early universe, as well as comparing observations with cosmological models, and is part of the core team analysing data from the Planck satellite.
  • Jacob Dunningham (now Professor of Physics)  – Jacob is Head of the Atomic Molecular & Optical (AMO) Physics group at Sussex  and works on quantum mechanical entanglement spans the fields of quantum information, quantum optics, Bose-Einstein condensation, and metrology.

As former  Head of School  I knew these were in the system but I left before the somewhat laborious promotions process was completed, so it’s very nice to receive confirmation that they all went through.

P.S. Extra-special congratulations to Kathy, because she was born on Tyneside (i.e. not in the Midlands).

 

50 Years of the Astronomy Centre at the University of Sussex

Posted in Biographical, Education, The Universe and Stuff with tags , , , , , on October 18, 2016 by telescoper

On Saturday (15th October) I was back in Brighton for the first time since I left my job there at the end of July. The occasion was a very nice lunch party to celebrate 50 years of the Astronomy Centre at the University of Sussex, which started properly in 1966. It was a pleasant occasion, and great to have the chance to catch up with some people I haven’t seen for far too long. I had two stints in the Astronomy Centre: once as a student then postdoc from 1985 to 1990, and the other from 2013 to 2016 when I was Head of the School of which the Astronomy Centre is part. I had a lot more time to do research in the first incarnation than in the second!

Quite a few people present hadn’t realised I was no longer working at Sussex, which led to one or two slightly awkward conversations, but I was thankfully very far from being the centre of attention.

After the lunch itself we had short speeches from various alumni of the Astronomy Centre: esteemed science writer John Gribbbin (who was one of its first MSc students in 1966); Lord Martin Rees (who was briefly a Professor at Sussex, before he returned to Cambridge to take up the Plumian Professorship); John Barrow (who was my supervisor while I was there); Carlos Frenk (who was a postdoctoral researcher when I arrived in September 1985, but who left to take up a lectureship in Durham at the end of that year so we overlapped only for a short time); Andrew Liddle (who arrived near the end of my stay and was there for 22 years altogether, leaving at the end of 2012 to take up a post in Edinburgh); and Peter Thomas (current Director of the Astronomy Centre).

When I arrived in 1985 there were only four permanent faculty in the Astronomy Centre itself – Roger Tayler, Leon Mestel, John Barrow and Robert Smith – but research there was thriving and it was a great environment to work in. I count myself very lucky at having made such a good choice of a place to do my PhD DPhil. Leon and Robert both worked on stellar astrophysics, but after Leon’s retirement the centre increasingly focussed on cosmology and extragalactic astrophysics, which remains the case today. Roger Tayler sadly passed away in 1997, but Leon is still around: he is 89 years old and now lives in Cambridge.

Those present at the lunch were given a booklet featuring around 50 academic papers or other research “highlights”(e.g. the launch of Planck), approximately one for each year of the Astronomy Centre, chosen to be the “best” of that year. Each page was also shown as a slide during the lunch. I was thrilled to see that two of my papers (from 1987 and 1991 respectively) made it into the collection. The second one was published after I’d left Sussex, but I definitely did the work on it and submitted it while an employee of the Astronomy Centre. Andrew Liddle and John Barrow have the largest number of “greatest hits”, but the most famous paper is probably the classic “DEFW” which won Carlos Frenk and his collaborators the Gruber Prize about five years ago.

The book also contains various bits of interesting bibliometric information, such as this, which shows that the variation in the productivity of the Astronomy Centre over time.

us-astronomy-50-powerpoint

Anyway, for those who are interested, the whole collection of slides can be viewed here:

Thanks to Seb Oliver and the rest of the Astronomy Centre for organizing this very enjoyable event – and for sending me the slides! Here’s to the next 50 years of Astronomy at the University of Sussex!

 

Rank Nonsense

Posted in Bad Statistics, Education, Politics with tags , , , , , on September 8, 2016 by telescoper

It’s that time of year when international league tables (also known as “World Rankings”)  appear. We’ve already had the QS World University Rankings and the Shanghai (ARWU) World University Rankings. These will soon be joined by the Times Higher World Rankings, due out on 21st September.

A lot of people who should know a lot better give these league tables far too much attention. As far as I’m concerned they are all constructed using extremely suspect methodologies whose main function is to amplify small statistical variations into something that looks significant enough to justify constructing  a narrative about it. The resulting press coverage usually better reflects a preconceived idea in a journalist’s head than any sensible reading of the tables themselves.

A particularly egregious example of this kind of nonsense can be found in this week’s Guardian. The offending article is entitled “UK universities tumble in world rankings amid Brexit concerns”. Now I make no secret of the fact that I voted “Remain” and that I do think BrExit (if it actually happens) will damage UK universities (as well as everything else in the UK). However, linking the changes in the QS rankings to BrExit is evidently ridiculous: all the data were collected before the referendum on 23rd June anyway! In my opinion there are enough good arguments against BrExit without trying to concoct daft ones.

In any case these tables do not come with any estimate of the likely statistical variation from year to year in the metrics used to construct them, which makes changes impossible to interpret. If only the compilers of these tables would put error bars on the results! Interestingly, my former employer, the University of Sussex, has held its place exactly in the QS rankings between 2015 and 2016: it was ranked 187th in the world in both years. However, the actual score corresponding to these two years was 55.6 in 2015 and 48.4 in 2016. Moreover, Cambridge University fell from 3rd to 4th place this year but its score only changed from 98.6 to 97.2. I very much doubt that is significant at all, but it’s mentioned prominently in the subheading of the Guardian piece:

Uncertainty over research funding and immigration rules blamed for decline, as Cambridge slips out of top three for first time.

Actually, looking closer, I find that Cambridge was joint 3rd in 2015 and is 4th this year. Over-interpretation, or what?

To end with, I can’t resist mentioning that the University of Sussex is in the top 150 in the Shanghai Rankings for Natural and Mathematical Sciences this year, having not been in the top 200 last year. This stunning improvement happened while I was Head of School for Mathematical and Physical Sciences so it clearly can not be any kind of statistical fluke but is entirely attributable to excellent leadership. Thank you for your applause.