Archive for University of Sussex

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.

 

 

Universities must do more to stop violence

Posted in Education, Uncategorized with tags , on August 15, 2016 by telescoper

I’ve thought very hard over the last couple of days about whether to comment on the shocking case reported by the Independent last week of a (male) senior lecturer (Dr Lee Salter) at Sussex University who beat up a (female) student with whom he had been having an affair. In the end I decided that I had to comment, as the case raises some very important questions.

I didn’t know anything about this until last week so I have nothing to add to the account of the events and subsequent criminal conviction given in the newspaper and suggest you read the details there. I will restrict my comments to the wider issues.

On Friday 12th August, shortly after the news broke of Lee Salter’s conviction, the University released a statement which I thought raised more questions than it answered. It  subsequently updated the statement to say that Dr Salter was no longer an employee of the University. Whether that means he was dismissed or that he resigned is not clear.

Among the statements made by the University in its press release is the following:

The University does not tolerate violence of any kind. However, in cases involving criminal charges, it is important that such matters are dealt with by the police and the courts, which take precedence over employment procedures. Pending the outcome of the criminal proceedings, the University kept the situation under review and monitored and assessed any risk to its students.

In my role as a Head of School at Sussex (a job I left just a couple of weeks ago), I had to deal with some disciplinary matters  so I’m very familiar with the content of the relevant procedures. In fact I did more of these than you’d probably imagine, though I can’t write about the details because they are bound by confidentiality.

It is indeed the case that if a disciplinary case involves criminal elements then the established practice is to let the courts decide first before continuing with the disciplinary investigation. For one thing, a conviction in a criminal case usually makes the subsequent internal investigation simpler.

Acquittal in a criminal case does not mean dropping the disciplinary, however, as the standard of proof in a criminal case (“beyond reasonable doubt”) is stronger than that of an internal investigation which is that of a civil court (“on the balance of the evidence”). It is quite possible for the latter standard to be met when the former is not. So it was reasonable for the University to wait for the outcome of the criminal trial before proceeding.

However, the University of Sussex’s own disciplinary procedure also states:

“The University will take disciplinary action in accordance with its procedures against anyone who behaves in a violent manner including, should it be necessary, the immediate exclusion of the perpetrator from the campus.

Based on the account given in the Independent I find it difficult to understand why the University did not take this course of action in this case.

Of course a suspect is innocent until proven guilty, but suspension (paid) and exclusion from campus would not, in my view, have been unnecessarily prejudicial given the seriousness of the charges. Salter would not have been able to do teaching, but could have carried on research from home. The University’s failure to take this step is extremely worrying as in my view it gives inadequate consideration to the effect on the victim of the continued presence of the perpetrator.

For the record I should state that I have very good reasons for having zero tolerance to any form of violence, whether committed by staff or students or political protestors or security guards. You can read why here.

I’ve blogged before about the difficulties surrounding confidentiality and other issues disciplinary procedures in the context of sexual harassment. In that piece – which was actually about science departments – I tried to stress the importance of sticking to proper procedure, but I also explained that dealing with such matters after the fact is never going to provide a fully satisfactory remedy. What is needed is to change campus culture to ensure that abusive harassing and violent behaviour doesn’t happen in the first place. But applying procedures properly would at least be a start…

 

 

 

 

The Rising Stars of Sussex Physics

Posted in Bad Statistics, Biographical, Education with tags , , , , on July 28, 2016 by telescoper

This is my penultimate day in the office in the School of Mathematical and Physical Sciences at the University of Sussex, and a bit of news has arrived that seems a nice way to round off my stint as Head of School.

It seems that Physics & Astronomy research at the University of Sussex has been ranked as 13th in western Europe and 7th in the UK by leading academic publishers, Nature Research, and has been profiled as one of its top-25 “rising stars” worldwide.

I was tempted to describe this rise as ‘meteoric’ but in my experience meteors generally fall down rather than rise up.

Anyway, as regular readers of this blog will know, I’m generally very sceptical of the value of league tables and there’s no reason to treat this one as qualitatively any different. Here is an explanation of the (rather curious) methodology from the University of Sussex news item:

The Nature Index 2016 Rising Stars supplement identifies the countries and institutions showing the most significant growth in high-quality research publications, using the Nature Index, which tracks the research of more than 8,000 global institutions – described as “players to watch”.

The top 100 most improved institutions in the index between 2012 and 2015 are ranked by the increase in their contribution to 68 high-quality journals. From this top 100, the supplement profiles 25 rising stars – one of which is Sussex – that are already making their mark, and have the potential to shine in coming decades.

The institutions and countries examined have increased their contribution to a selection of top natural science journals — a metric known as weighted fractional count (WFC) — from 2012 to 2015.

Mainly thanks to a quadrupling of its physical sciences score, Sussex reached 351 in the Global 500 in 2015. That represents an 83.9% rise in its contribution to index papers since 2012 — the biggest jump of any UK research organisation in the top 100 most improved institutions.

It’s certainly a strange choice of metric, as it only involves publications in “high quality” journals, presumably selected by Journal Impact Factor or some other arbitrary statistical abominatio,  then taking the difference in this measure between 2012 and 2015  and expressing the change as a percentage. I noticed one institution in the list has improved by over 4600%, which makes Sussex’s change of 83.9% seem rather insignificant…

But at least this table provides some sort of evidence that the investment made in Physics & Astronomy over the last few years has made a significant (and positive) difference. The number of research faculty in Physics & Astronomy has increased by more than 60%  since 2012 so one would have been surprised not to have seen an increase in publication output over the same period. On the other hand, it seems likely that many of the high-impact papers published since 2012 were written by researchers who arrived well before then because Physics research is often a slow burner. The full impact of the most recent investments has probably not yet been felt. I’m therefore confident that Physics at Sussex has a very exciting future in store as its rising stars look set to rise still further! It’s nice to be going out on a high note!