Archive for March, 2018

Why Physicists Leave Physics

Posted in Uncategorized on March 31, 2018 by telescoper

Interesting post. Only about one in twenty PhDs go on to be professors in the long run. People leave academia for various reasons, not all of them negative, but I still think we overproduce PhDs in the UK. There has never been a proper study of the merits of funding fewer PhDs and more Masters degrees, for example.

4 gravitons

It’s an open secret that many physicists end up leaving physics. How many depends on how you count things, but for a representative number, this report has 31% of US physics PhDs in the private sector after one year. I’d expect that number to grow with time post-PhD. While some of these people might still be doing physics, in certain sub-fields that isn’t really an option: it’s not like there are companies that do R&D in particle physics, astrophysics, or string theory. Instead, these physicists get hired in data science, or quantitative finance, or machine learning. Others stay in academia, but stop doing physics: either transitioning to another field, or taking teaching-focused jobs that don’t leave time for research.

There’s a standard economic narrative for why this happens. The number of students grad schools accept and graduate is much higher than the number of professor jobs. There simply isn’t room…

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Stephen Hawking Remembered

Posted in Uncategorized on March 30, 2018 by telescoper

I wasn’t really planning to post anything over this Easter break but I thought I’d make a small exception just to direct you to a radio programme and podcast that I contributed to about Stephen Hawking, who died recently.

You can find the link to a podcast of the episode of Pythagoras’ Trousers originally broadcast on Radio Cardiff that features my ramblings, as well as a longer, unedited version of the interview I contributed, with some more technical content, here.

And let me also take the opportunity to send my best wishes to everyone of any faith or none over the forthcoming holiday!

Uncommon Travel Experiences

Posted in Biographical with tags , , on March 29, 2018 by telescoper

Back in Cardiff for the Easter weekend – which I am to spend mainly sleeping – after flying back this morning from Dublin, I thought I’d do a brief post about a fairly strange thing that happened when I got to Cardiff Airport this morning.

I’ve done this flight many times over the past few months and arrival at Cardiff has always been the same story: passengers disembark and walk through a special arrival gate marked `Channel Islands and Republic of Ireland’. This leads past a couple of desks (marked security) which have always been unoccupied and straight into the baggage reclaim area. This morning, however, there were 3-4 police and/or UKBA people and they checked everybody’s passport who was on the flight from Dublin.

This is quite irregular, as there is supposed to be a Common Travel Area including the UK and Ireland (as well as the Channel Islands and the Isle of Man), and passport checks are not routinely made at borders within the CTA. They never have been to date on any of the trips I’ve made.

So what was going on? Was it some sort of rehearsal for the post-Brexit era (which may well see the end of the CTA, as there is likely to be a hard border between the UK and Ireland)?

I suspect not. One possibility is that the Police were actually looking for someone or something specific. Although passport checks are not routinely made, there is no law forbidding them if there’s a reason to make them. In fact the CTA is the result of informal agreements rather than domestic laws or international treaties so it’s not legally enforceable in any case.

However, I think a likelier explanation is connected to the reason why the flight was late departing from Dublin. The computer system that is linked to the automatic boarding pass reader at the departure gate seemed not to be working. The Flybe staff there had to check every document by hand, and cross names off a printed list as they went through the departure gate. The final tally of passengers also took a while to produce, so we left about 25 minutes late.

I suspect that whatever the problem was with Flybe’s systems, some of the passenger data usually registered for each flight was not available. When authorities at Cardiff were informed about this, an additional precautionary check was performed. I think this is a good theory, as it provides a unified explanation of two unique phenomena (unique in my experience of the Dublin-Cardiff route, that is).

Anyway, although I was surprised at to find uniformed people checking passports when I arrived, and mildly concerned that I might miss the 10.00am bus from the airport to Cardiff, I have travelled enough to realise that it’s never a good idea to make a fuss or even a joke when immigration officers are involved; it never achieves anything and they rarely possess even the most rudimentary sense of humour. And I got on the bus with plenty of time to spare….

Incidentally, when arriving in Dublin from Cardiff there is no specific arrival area for passengers from the UK who must proceed to passport control along with everyone else. A person travelling from the UK to Ireland does not have to show a passport – an ID card will suffice – but the UK does not have a system of ID cards so the only photo-identification most of us have is a passport. In practice, therefore, I show my passport when I arrive. In fact I usually show it to the automatic barrier that reads e-passports, which is far quicker than joining the queue for those with old passports or other forms of ID. At least the automatic machines work in Dublin…

The LGBT+ Physical Sciences Climate Survey – Reminder

Posted in LGBT with tags , , , on March 28, 2018 by telescoper

An email from the Institute of Physics yesterday reminded me to remind you all to participate (if you are so minded) in the LGBT+ Physical Sciences climate survey, which was launched amid the snows of 1st March this year.

As it happens, an IOP photographer was on hand to capture these images of yours truly giving a speech to open the event and chairing the subsequent panel:

The survey is open to members and non-members of professional organisations who identify as LGBT+ or allies and who may be working, teaching or studying in a physical sciences field. Respondents will need to be at least 16 years of age and above. The Institute of Physics (IOP), Royal Astronomical Society (RAS) and Royal Society of Chemistry (RSC) are managing this survey on behalf of the LGBT+ Physical Sciences Network. Its aim is to collect evidence for what the working and studying climate is like for LGBT+ physical scientists in the UK and Ireland.

You can complete the survey here.

The survey is open until Monday 30th April, but why not do it right away?

A Day at DIAS

Posted in Biographical, Books, Talks and Reviews with tags , , on March 27, 2018 by telescoper

Last night I flew back to Ireland for a few days of work here before the Easter Weekend. The schedule of flights from Cardiff to Dublin has changed for the spring, with the afternoon flight much later: at 7.45pm instead of 3.40pm, so I left from Cardiff after work on Monday and had dinner in the airport (an overpriced and barely edible beefburger).

Although there is no teaching in either on Maynooth or Cardiff this week I had to come to Ireland for a few reasons, including giving a seminar today at the Dublin Institute for Advanced Studies (DIAS) this afternoon which provided me with the chance to visit it for the first time.

It being a pleasant morning I walked to DIAS from Connolly Station after taking the train there from Maynooth. It’s about half an hour’s walk.

DIAS is actually spread over several sites. Officially my talk was at the School of Theoretical Physics, but there were some people there from the School of Cosmic Physics, which is located not too far away. There were also a few people from Maynooth there, as there are a number of collaborations going on between the two institutions involving staff and students. There was also a visitor from even further afield, in the form of Cormac O’Rafferty who also visits this blog from time to time.

Anyway I had a nice curry for lunch before the talk, which generated a lot of questions from which I infer that it was either confusing or stimulating (or possibly both). Here are the slides in case anyone feels like taking a look.

For a change I decided to take the train back to Maynooth from Pearse rather than Connolly, but as it was rush hour I found it packed.

Maynooth by contrast is very quiet with most students away for the break. I can also report that the annoying roadworks that have been going outside my Maynooth residence for months have now finished.

Anyway, thanks to my hosts at DIAS for inviting me and I hope my talk was reasonably bearable. Hopefully this will be the first visit of many!

Is the Cosmological Flatness Problem really a problem?

Posted in The Universe and Stuff, Bad Statistics with tags , , on March 26, 2018 by telescoper

A comment elsewhere on this blog drew my attention to a paper on the arXiv by Marc Holman with the following abstract:

Modern observations based on general relativity indicate that the spatial geometry of the expanding, large-scale Universe is very nearly Euclidean. This basic empirical fact is at the core of the so-called “flatness problem”, which is widely perceived to be a major outstanding problem of modern cosmology and as such forms one of the prime motivations behind inflationary models. An inspection of the literature and some further critical reflection however quickly reveals that the typical formulation of this putative problem is fraught with questionable arguments and misconceptions and that it is moreover imperative to distinguish between different varieties of problem. It is shown that the observational fact that the large-scale Universe is so nearly flat is ultimately no more puzzling than similar “anthropic coincidences”, such as the specific (orders of magnitude of the) values of the gravitational and electromagnetic coupling constants. In particular, there is no fine-tuning problem in connection to flatness of the kind usually argued for. The arguments regarding flatness and particle horizons typically found in cosmological discourses in fact address a mere single issue underlying the standard FLRW cosmologies, namely the extreme improbability of these models with respect to any “reasonable measure” on the “space of all space-times”. This issue may be expressed in different ways and a phase space formulation, due to Penrose, is presented here. A horizon problem only arises when additional assumptions – which are usually kept implicit and at any rate seem rather speculative – are made.

It’s an interesting piece on a topic that I’ve blogged about before. I think it’s well worth reading because many of the discussions of this issue you will find in the literature are very confused and confusing. Apart from mine of course.

Debussy, Mozart and Messiaen at St David’s Hall

Posted in Music with tags , , , , , , on March 25, 2018 by telescoper

The view from Tier 2 before the concert

After work (and a pint or two) on Friday evening I headed to St David’s Hall for a concert by the BBC National Orchestra of Wales conducted by Jac van Steen. The concert was broadcast live on BBC Radio 3 so you can listen to it on the iPlayer for a month.

Two of the four pieces on the programme were by Claude Debussy (abovel, to mark the centenary of his death which was 100 years ago today (on 25th March 1918).

The concert opened with Debussy’s Nocturnes and ended with La Mer , both works consisting of three movements for a large orchestra and showing the vivid chromaticism and lush orchestration that typifies so many of his compositions. The last movement of Nocturnes includes some wordless singing, which was performed beautifully by female singers from the Royal Welsh College of Music and Drama.

The second piece was Mozart’s Piano Concerto No. 27 in B flat Major K. 595, with soloist Steven Osborne. This, Mozart’s last piano concerto, is a nice piece, well played by both pianist and (pared-down) orchestra but I felt it was a rather incongruous choice for this programme. It was probably chosen because it is in some sense a valedictory piece, but all it did for me in this concert was emphasize how much the harmonic vocabulary of music expanded between Mozart and Debussy, and left me feeling that the Mozart piece was rather trite in comparison.

After the wine break we heard a piece that was completely new to me, Les Offrandes Oubliées by Olivier Messiaen, a wonderfully expressive piece with wildly contrasting moods, clearly influenced by Debussy but with a distinctive voice all its own. Messiaen is one composer I definitely wish I knew more about.

After the superb La Mer which ended the published programme, something very unusual happened for a classical concert in the UK: there was an encore by the orchestra in the form of a dance by Debussy orchestrated by Maurice Ravel.

All in all, a very enjoyable evening and a fitting tribute to Claude Debussy, a composer who was both modernist and impressionist and whose influence on the development of music is incalculable.