Newcastle Joins the Resurgence of UK Physics

Posted in Education, Science Politics, The Universe and Stuff with tags , , , on August 17, 2014 by telescoper

I’ve posted a couple of times about how Physics seems to undergoing a considerable resurgence in popularity at undergraduate level across the United Kingdom, with e.g. Lincoln University setting up a new programme. Now there’s further evidence in that Newcastle University has now decided to re-open its Physics course for 2015 entry.

The University of Newcastle had an undergraduate course in Physics until 2004 when it decided to close it down, apparently owing to lack of demand. They did carry on doing some physics research (in nanoscience, biophysics, optics and astronomy) but not within a standalone physics department. The mid-2000s were tough for UK physics,  and many departments were on the brink at that time. Reading, for example, closed its Physics department in 2006; there is talk that they might be starting again too.

The background to the Newcastle decision is that admissions to physics departments across the country are growing at a healthy rate, a fact that could not have been imagined just ten years ago. Times were tough here at Sussex until relatively recently, but now we’re expanding on the back of increased student numbers and research successes. Indeed having just been through a very busy clearing and confirmation period at Sussex University, it is notable that its the science Schools that have generally done best.  Sussex has traditionally been viewed as basically a Liberal Arts College with some science departments; over 70% of the students here at present are not studying science subjects. With Mathematics this year overtaking English as the most popular A-level choice, this may well change the complexion of Sussex University relatively rapidly.

I’ve always felt that it’s a scandal that there are only around 40 UK “universities” with physics departments Call me old-fashioned, but I think a university without a physics department is not a university at all; it’s particularly strange that a Russell Group university such as Newcastle should not offer a physics degree. I believe in the value of physics for its own sake as well as for the numerous wider benefits it offers society in terms of new technologies and skills. Although the opening of a new physics department will create more competition for the rest of us, I think it’s a very good thing for the subject and for the Higher Education sector general.

That said, it won’t be an easy task to restart an undergraduate physics programme in Newcastle, especially if it is intended to have as large an intake as most successful existing departments (i.e. well over 100 each year). Students will be applying in late 2014 or early 2015 for entry in September 2015. The problem is that the new course won’t figure in any of the league tables on which most potential students based their choice of university. They won’t have an NSS score either. Also their courses  will probably need some time before it can be accredited by the Institute of Physics (as most UK physics courses are).

There’s a lot of ground to make up, and my guess is that it will take some years to built up a significant intake.The University bosses will therefore have to be patient and be prepared to invest heavily in this initiative until it can break even. The decision a decade ago to cut physics doesn’t exactly inspire confidence that they will be prepared to do this, but times have changed and so have the people at the helm so maybe that’s an unfair comment.

There are also difficulties on the research side (which is also vital for a proper undergraduate teaching programme), there are also difficulties. Grant funding is already spread very thin, and there is little sign of any improvement for the foreseeable future  in the “flat cash” situation we’re currently in. There’s also the stifling effect of theResearch Excellence Framework I’ve blogged about before. I don’t know whether Newcastle University intends to expand its staff numbers in Physics or just to rearrange existing staff into a new department, but if they do the former they will have to succeed against well-established competitors in an increasingly tight funding regime. A great deal of thought will have to go into deciding which areas of research to develop, especially as their main regional competitor, Durham University, is very strong in physics.

On the other hand, there are some positives, not least of which is that Newcastle is and has always been a very popular city for students (being of course the finest city in the whole world). These days funding follows students, so that could be a very powerful card if played wisely.

Anyway, these are all problems for other people to deal with. What I really wanted to do was to wish this new venture well and to congratulate Newcastle on rejoining the ranks of proper universities (i.e. ones with physics departments). Any others thinking of joining the club?

A Keno Game Problem

Posted in Cute Problems with tags , , , , on July 25, 2014 by telescoper

It’s been a while since I posted anything in the Cute Problems category so, given that I’ve got an unexpected gap of half an hour today, I thought I’d return to one of my side interests, the mathematics and games and gambling.

There is a variety of gambling games called Keno games in which a player selects (or is given) a set of numbers, some or all of which the player hopes to match with numbers drawn without replacement from a larger set of numbers. A common example of this type of game is Bingo. These games mostly originate in the 19th Century when travelling carnivals and funfairs often involved booths in which customers could gamble in various ways; similar things happen today, though perhaps with more sophisticated games.

In modern Casino Keno (sometimes called Race Horse Keno) a player receives a card with the numbers from 1 to 80 marked on it. He or she then marks a selection between 1 and 15 numbers and indicates the amount of a proposed bet; if n numbers are marked then the game is called `n-spot Keno’. Obviously, in 1-spot Keno, only one number is marked. Twenty numbers are then drawn without replacement from a set comprising the integers 1 to 80, using some form of randomizing device. If an appropriate proportion of the marked numbers are in fact drawn the player gets a payoff calculated by the House. Below you can see the usual payoffs for 10-spot Keno:

If fewer than five of your numbers are drawn, you lose your £1 stake. The expected gain on a £1 bet can be calculated by working out the probability of each of the outcomes listed above multiplied by the corresponding payoff, adding these together and then subtracting the probability of losing your stake (which corresponds to a gain of -£1). If this overall expected gain is negative (which it will be for any competently run casino) then the expected loss is called the house edge. In other words, if you can expect to lose £X on a £1 bet then X is the house edge.

What is the house edge for 10-spot Keno?

Time for a Factorial Moment…

Posted in Bad Statistics with tags , , on July 22, 2014 by telescoper

Another very busy and very hot day so no time for a proper blog post. I suggest we all take a short break and enjoy a Factorial Moment:

I remember many moons ago spending ages calculating the factorial moments of the Poisson-Lognormal distribution, only to find that they were well known. If only I’d had Google then…

Mathematics and Meningococcal Meningitis

Posted in Education, Science Politics with tags , , , , on June 9, 2014 by telescoper

Last week I attended a very enjoyable and informative event entitled Excellence with Impact that showcased some of the research that the University of Sussex submitted to the 2014 Research Excellence Framework. One of the case studies came from the Department of Mathematics which is part of the School of Mathematical and Physical Sciences (of which I am Head) so I thought I would showcase it here too:

Meningococcal meningitis is a debilitating and deadly disease, causing an estimated 10,000 deaths annually in endemic areas of sub-Saharan Africa. A novel mathematical model developed by Sussex researcher Dr Konstantin Blyuss and colleagues has helped explain the patterns of the dynamics of meningococcal meningitis in endemic areas. This model is now being used by epidemiologists and clinical scientists to design and deliver efficient public-health policies to combat this devastating disease.

You can find out more by following this link.

Lincoln – Green Shoots for Maths and Physics?

Posted in Education with tags , , , , on March 3, 2014 by telescoper

I noticed over the weekend that there’s a job being advertised at the University of Lincoln designated Founding Head of the School of Mathematics and Physics. It seems the powers that be at Lincoln University (which is in the Midlands) have decided to set up an entire new activity in Mathematics and Physics. I’m pointing this out not because of any personal connection with the position, but because it’s refreshing to see a new(ish) Higher Education Institute apparently willing to take the plunge and invest in a new venture, particularly because it includes Physics. It wasn’t at all long ago that UK Physics departments were being closed down – the University of Reading being a prominent example, in 2006. I think Reading is thinking of starting up Physics again, in fact. Perhaps these are the green shoots that presage a new spring for Physics in this country? I do hope so.

It won’t be an easy task to start up a new department from scratch in Lincoln: grant funding is tight and the competition for students among established institutions is already so intense that it will be very difficult for a brand new outfit to break through. Nevertheless, I think it’s a praiseworthy initiative and I wish it well.

From Real Time to Imaginary Time

Posted in Brighton, Education, The Universe and Stuff with tags , , , , , , , , , , , on February 24, 2014 by telescoper

Yesterday, after yet another Sunday afternoon in my office on the University of Sussex campus, I once again encountered the baffling nature of the “real time boards” at the bus-stop at Falmer Station (just over the road from the University). These boards are meant to show the expected arrival times of buses; an example can be seen on the left of the picture below, taken at Churchill Square (in the City Centre).

The real-time board system works pretty well in central Brighton, but it’s a very different story at Falmer, especially for the Number 23 which is my preferred bus home. Yesterday provided a typical illustration of the problem: the time of the first bus on the list, a No. 23, was shown as “1 min” when I arrived at the stop. It then quickly moved to “due” (a word which I’ll comment about later). It then moved back to “2 mins” for about 5 minutes and then back to “due” again. It stayed like that for over 10 minutes at which point the bus that was second on the list (a No. 28 from Lewes) appeared. Rather than risk waiting any longer for the 23 I got on the 28 and had a slightly longer walk home from the stop at the other end. Just as well I did because the 23 vanished entirely from the screen as soon as I boarded the other bus. This apparent time-travel isn’t unusual at Falmer, although I’ve never really understood why.

By sheer coincidence when I got to the bus stop to catch a bus to campus this morning there was a chap from Brighton and Hove buses there. He was explaining what sometimes goes wrong with the real time boards to a lady, so I joined in the conversation and asked him if he knew why Falmer is so unreliable. He was happy to oblige. It turns out that the way the real-time boards work depends on each bus having a GPS system that communicates to a central computer via a radio link. If the radio link drops out for some reason – as it apparently does quite often up at Falmer (mobile phone connectivity is poor here also) – the system looks up the expected time of the bus after the one that it has lost contact with. Thus it is that a bus can apparently be “due” and then apparently go back in time. Also, if a bus has to divert from the route programmed into the GPS tracker then it is also removed from the real-time boards.

However, there is another system in operation alongside the GPS tracker. When a bus actually stops at a stop and opens its doors the onboard computer communicates this to the central system at the same time as the location signs inside the bus are updated. At this point the real-time boards are reset.

The unreliability I’ve observed at Falmer is in fact caused by two problems: (i) the patchy radio coverage as the bus wanders around the hilly environs of Falmer campus; and (ii) the No. 23 is on a new route around the back of campus which means that it vanishes from the system entirely when it wanders off the old route, as would happen if the bus were to break down.

Mystery solved then, in a sense, but it means there’s a systematic problem that isn’t going to be fixed in the short-term. Would it be better to switch off the boards than have them show inaccurate information? Perhaps, but only if it were always wrong. In fact the boards seem to work OK for the more frequent bus, the No. 25. My strategy is therefore never to rely on the information provided concerning the No. 23 and just get the first bus that comes. It’s not a problem anyway during the week because there’s a bus every few minutes, but on a Sunday evening it is quite irksome to see apparently random times on the screens.

All this talk about real-time boards reminds me of a question I was asked in a lecture last week. I was starting a new section of my Theoretical Physics module for 2nd Year students on Complex Analysis: the Cauchy-Riemann equations, Conformal Transformations, Contour Integrals and all that Jazz. To start the section I went on a bit of a ramble about the ubiquity of complex numbers in physics and whether this means that imaginary numbers are, in some sense, real. You can find an enjoyable polemic on this subject, given the answer “no” to the question here.

Anyway, I got the class to suggest examples of the use of complex numbers in physics. The things you’d expect came up such as circuit theory, wave propagation etc. Then somebody mentioned that somewhere they had heard of imaginary time. The context had probably been provided Stephen Hawking who mentioned this in his book A Brief History of Time. In fact the trick of introducing imaginary time is called a Wick Rotation and the basic idea is simple. In special relativity we deal with four-dimensional space-time intervals of the form

$ds^2 = -c^2dt^2 + dx^2 + dy^2 +dz^2$,

i.e. the metric describing Minkowski space. The minus sign in front of the time bit is essential to the causal structure of space-time but it causes quite a few mathematical difficulties. However if we make the substitution

$\tau \rightarrow i c t$

then the metric becomes

$ds^2 = d\tau^2 + dx^2 + dy^2 +dz^2$,

which corresponds to a four-dimensional Euclidean space which is in many situations much easier to handle mathematically.

Complex variables and complex functions provide the theoretical physicist with a host of extremely elegant techniques for solving tricky problems. But does that mean they are somehow “built in” to nature? I don’t think so. I don’t think the Brighton & Hove Bus company uses imaginary time on its display boards either, although it does sometimes seem that way.

POSTSCRIPT. I forgot to include my planned rant about the use of the word “due”. The boards displaying train times at railway stations usually give the destination and planned departure time of the train, e.g. “Brighton 11.15″. If things are running to schedule this information is supplemented by the phrase “On Time”. If not, which is sadly a more likely contingency in the UK, this changes to “due 11.37″ or some such. This really annoys me.: the train is due at 11.15. If it doesn’t come until after then, it’s overdue or, in other words, late.

The most beautiful equation?

Posted in The Universe and Stuff with tags , , , , on February 13, 2014 by telescoper

There’s an interesting article on the BBC website today that discusses the way mathematicians’ brains appear to perceive “beauty”. A (slightly) more technical version of the story can be found here. According to functional magnetic resonance imaging studies, it seems that beautiful equations excite the same sort of brain activity as beautiful music or art.

The question of why we think equations are beautiful is one that has come up a number of times on this blog. I suspect the answer is a slightly different one for theoretical physicists compared with pure mathematicians. Anyway, I thought it might be fun to invite people offer suggestions through the comments box as to the most beautiful equation along with a brief description of why.

I should set the ball rolling myself, and I will do so with this, the Dirac Equation:

This equation is certainly the most beautiful thing I’ve ever come across in theoretical physics, though I don’t find it easy to articulate precisely why. I think it’s partly because it is such a wonderfully compact fusion of special relativity with quantum mechanics but also partly because of the great leaps of the imagination that were needed along the journey to derive it and consequent admiration for the intellectual struggle involved. I feel it is therefore as much an emotional response to the achievement of another human being – such as one feels when hearing great music or looking at great art – as it is a rational response to the mathematical structure involved.

Anyway, feel free to suggest formulae or equations through the comments box, preferably with a brief explanation of why you think they’re so beautiful.