Archive for May, 2021

Life is too short…

Posted in Biographical, Maynooth on May 31, 2021 by telescoper

Today not being a bank holiday in Ireland – though it is in the UK, it’s our turn next Monday – I’ve been trying to finish off my examination marking and haven’t had time to write a proper post. Instead of doing that I thought I’d share the following picture, which I found on Facebook. It’s from the Technische Universität Kaiserslautern. I hope my colleagues in the Department of Experimental Physics don’t take offence!

Lest anyone gets the wrong idea about my view of the Experimental versus Theoretical Physics
divide, let me repeat some thoughts I posted a while ago.

Regular readers of his blog will know that here at Maynooth University there are two Physics departments, one the Department of Theoretical Physics (of which I am a Faculty member) and the other the Department of Experimental Physics. These two units are in the same building but have so far have been largely separate in terms of teaching and research; Experimental Physics (EP) is somewhat larger in terms of staff and student numbers than Theoretical Physics (TP).

For instance, when students enter on our General Science degree programme they have to choose four subjects in the first year, including Mathematics (much as I did when I did my Natural Sciences degree at Cambridge back in the day). Picking `double physics’ (i.e. Experimental Physics and Theoretical Physics) uses up two of those choices, whereas Physics was a single choice in the first year of my degree. In the second year of this programme students do three subjects so can continue with both Theoretical and Experimental Physics (and another) , as they can in Year 3 where they do two subjects, and in Year 4 where they can do a single Major in either TP or EP or a double Major doing a bit of both.

To confuse matters still further, the Department of Theoretical Physics only changed its name from the Department of Mathematical Physics relatively recently and some of our documentation still carries that title. Quite often I get asked what’s the difference between Theoretical Physics and Mathematical Physics? As far as Maynooth is concerned we basically use those terms interchangeably and, although it might appear a little confusing at first, having both terms scattered around our webpages means that Google searches for both `Mathematical Physics’ and `Theoretical Physics’ will find us.

The Wikipedia page for Theoretical Physics begins

Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experimental tools to probe these phenomena.

This is what Wikipedia says about Experimental Physics:

Experimental physics is the category of disciplines and sub-disciplines in the field of physics that are concerned with the observation of physical phenomena and experiments. Methods vary from discipline to discipline, from simple experiments and observations, such as the Cavendish experiment, to more complicated ones, such as the Large Hadron Collider.

I count myself as a theoretical physicist (that’s what I did in Part II at Cambridge, anyway) though I do work a lot with data and many of the researchers in my discipline (cosmology) actually work at the interface between theory and experiment, so the distinction between theorists and experimentalists is perhaps not a very useful one.

As a matter of fact I think there’s a good case for theoretical physicists to have at least some experience of practical experimental work. There are two reasons for this:

  1. to understand about errors in measurement and how to treat them properly using statistical methods;
  2. to learn how easy it is to break expensive laboratory equipment.

In the past during Open Days I have asked the audience of prospective physics students if they could name a famous physicist. Most popular among the responses were the names you would have guessed: Einstein, Hawking, Feynman, Dirac, Newton, Schrodinger, and some perhaps less familiar names such as Leonard Susskind and Brian Greene. Every single one of these is (or was) a theorist of some kind. This is confirmed by the fact that many potential students mention similar names in the personal statements they write in support of their university applications. For better or worse, it seems that to some potential students at least Physics largely means Theoretical (or Mathematical) Physics.

Although it is probably good for our recruitment that there are so many high-profile theoretical physicists, it probably says more about how little the general public knows about what physics actually is and how it really works. No doubt there are many prospective students who are primarily drawn to laboratory work just as there are many drawn to theoretical calculations. But there are probably others whose interests encompass both. For me the important thing is the interplay between theory and experiment (or observation), as it is in that aspect where the whole exceeds the sum of the parts. Life is too short for arbitrary divisions!

The Tironian et…

Posted in History with tags , , , , , on May 30, 2021 by telescoper

Last week I had my last Irish language lesson at Level 1. Although I struggled to find the time to do anything outside the actual classes, and am consequently struggling generally with the language, I have enjoyed it a lot and do intend to go again next year to try to learn a bit more and get better at the basics.

One thing that came up in passing last week was the abbreviation “srl” which I’d seen a few times but although I didn’t understand it I didn’t ask – largely because there were so many other things I didn’t understand. Anyway, it turns out that “srl” is short for agus araile which means “and others”, so is the Irish equivalent of “etc” (et cetera in Latin).

In English “etc” can be abbreviated to &c, where the ampersand is a ligature of the e and t that make up “et” and so stands for “and”. After some googling and discussions on Twitter I learn that Old Irish had quite a lot of special symbols for abbreviations which are no longer used in modern Irish. In fact “srl” used to be “⁊rl” where the “⁊” is not a seven (7) but a Tironian et. It looks like 7 in modern typefaces but in older Irish script it looks more like the ligature “koto” found in Japanese (ヿ). Thys symbol is not entirely extinct – I’ve seen it a few times (e.g. above) and also on old post boxes. Here’s another example from a pub sign in Galway.

This is not a name, by the way. The sign means “bar” and “restaurant” (bialann = bia +-lann, the suffix “-lann” meaning place, usually an enclosed space, so it’s literally food place; the Irish word for “library” is leabharlann, srl.)

The Tironian et is one of the characters in a system of shorthand invented by Marcus Tullius Tiro, the slave (subsequently freed) who worked as private secretary to Cicero (aka Marcus Tullius Cicero). This system was used extensively in monasteries until the mediaeval period, which explains how its use came into Irish through Irish monks. It went out of fashion when printing presses became widely available and the Tironian et is one of the few still in use in the age of computers – it does have a unicode and is available in various fonts that come free with most operating systems in use today.

I think one of the reasons I am struggling to learn everyday Irish is that I keep going off at tangents like this, something I tend to do in all kinds of contexts.

Between Shots

Posted in Biographical, Covid-19 on May 29, 2021 by telescoper

The weather being rather pleasant today I had the chance to do a spot of gardening and hence chat to a couple of my neighbours outside at front of house about this that and the other. It turns out all three of us are between vaccine jabs, two having had a dose of Pfizer/BioNTech and the other one dose of AstraZeneca. None of us had any side effects after the first dose but are all now wondering when we’ll get our second. I expect I’ll get mine by mid-June sometime.

Official statistics on Ireland’s vaccination are no longer being published owing to the continuing disruption caused by a randsomware attack on the HSE computer systems, but the programme itself has not been affected by this and it is now believed that over 50% of the adult population has had its first jab.

However, this week we learned that Johnson & Johnson has joined AstraZeneca in not being able fulfil its contractual obligations and there might be a shortfall of several hundred thousand doses in June. It always seemed to me unlikely that Ireland would reach the Government’s target of 80% of the adult population vaccinated by the end of June, and now that looks virtually impossible.

Progress in vaccination will be a big factor in how we start teaching again next academic year, especially as it concerns the student population. We won’t know for a while how this will pan out so I’m trying not to think about it.

Of course there’s also the question of how many don’t take up the offer of a vaccine. I haven’t seen statistics on that but I hope it’s a small fraction. If people refuse their jabs, many may die needlelessly.

P.S. Can anyone suggest a plausible scientific explanation of why the lockdown has caused all my summer clothes to shrink?



More from the Dark Energy Survey

Posted in Astrohype, The Universe and Stuff with tags , , , , , , on May 28, 2021 by telescoper

To much media interest the Dark Energy Survey team yesterday released 11 new papers based on the analysis of their 3-year data. You can find the papers together with short descriptions here. There’s even a little video about the Dark Energy Survey here:

The official press release summarizes the results as follows:

Scientists measured that the way matter is distributed throughout the universe is consistent with predictions in the standard cosmological model, the best current model of the universe.

This contrasts a bit with the BBC’s version:

The results are a surprise because they show that it is slightly smoother and more spread out than the current best theories predict.

The observation appears to stray from Einstein’s theory of general relativity – posing a conundrum for researchers.

The reason for this appears to be that the BBC story focusses on the weak lensing paper (found here; I’ll add a link to the arXiv version if and when it appears there). The abstract is here:

The parameter S8 is a (slightly) rescaled version of the more familiar parameter σ8  – which quantifies the matter-density fluctuations on a scale of 8 h-1 Mpc – as defined in the abstract; cosmic shear is particularly sensitive to this parameter.

The key figure showing the alleged “tension” with Planck is here:

The companion paper referred to in the above abstract (found here has an abstract that concludes with the words (my emphasis).

We find a 2.3σ difference between our S8 result and that of Planck (2018), indicating no statistically significant tension, and additionally find our results to be in qualitative agreement with current weak lensing surveys (KiDS-1000 and HSC).

So, although certain people have decided to hype up a statistically insignificant l discrepancy, everything basically fits the standard model…

Meet the Astronomer Royal for Scotland!

Posted in Maynooth, The Universe and Stuff on May 27, 2021 by telescoper

I just heard this morning the wonderful news that Scotland has a new Astronomer Royal, in the form of Professor Catherine Heymans who is based at the Royal Observatory in Edinburgh. I am delighted to hear of this appointment! I have known Catherine for a long time from her work on cosmological applications of gravitational lensing. She was kind enough to visit us in Maynooth back in 2019 on University business and to meet Maynooth University Library Cat.

Catherine Heymans is the 11th Astronomer Royal for Scotland, succeeding Professor John Brown who passed away in 2019. She is also the first female holder of the title, in the 187 years since it was created.

I’m not exactly sure what is in the job description of Astronomer Royal for Scotland. I think it is largely an honorary title, but it will give Catherine a platform for outreach and other public activities which I’m sure she will do brilliantly, hopefully inspiring a future generation of female scientists in the process!

P.S. I can’t resist mentioning that I have posted a look-alike

R.I.P. Dave Carter

Posted in The Universe and Stuff on May 26, 2021 by telescoper

Dave Carter, photographed around 2001 by the Liverpool Telescope. Picture credit here.

It is with great sadness that I pass on the news of the death over the weekend of Professor David Carter of Liverpool John Moores University who, among many other things, was a regular commenter on this blog. I understand he had been suffering from leukemia for some time.

Dave Carter obtained his PhD from the Institute of Astronomy, Cambridge in 1977 working on the surface brightness profiles of galaxies. He then had a number of positions: at Oxford, at Mount Stromlo and Siding Spring Observatories in Australia, the Isaac Newton Group on La Palma and back in Cambridge. In 1996 he joined Liverpool John Moores University as Project Scientist for the Liverpool Telescope. He took early retirement from LJMU in 2012 but carried on research as an Emeritus Professor mainly working on the HST/ACS Coma Cluster survey.

His comments on this blog over the years – his first was in 2010 – revealed him to have a wide range of interests outside astronomy, including cricket and music. He was also involved in his local Methodist Church and Community Centre, and a local parish councillor.

I didn’t know Dave very well in a personal capacity – we only met in person a few times – but he always struck me as a very nice man as well as being immensely knowledgeable about matters astronomical. I send my deepest condolences to his wife and three sons, as well all his friends and colleagues both in Liverpool and around the world who miss him terribly.

The Burning of the Custom House

Posted in History with tags , , , , on May 25, 2021 by telescoper

Today is the centenary of a significant event in the War of Independence. On 25th March 1921 about 120 members of the Irish Republican Army mounted an operation in Dublin with the aim of setting fire to the Custom House, a fine 18th Century neoclassical building on the North Side of the River Liffey in central Dublin. They were aided in this task by members of the local Fire Brigade who, being Republican supporters, started by the IRA, did the best they could to spread the flames throughout the building when purportedly trying to put them out.

The destruction of the Custom House was a major propaganda coup for the Republican forces, but in military terms it was disastrous. About two-thirds of the IRA volunteers that took part were captured and five were killed. That meant that the virtual elimination of the fighting capability of the IRA in Dublin. The whole plan was the brainchild of Éamon de Valera, who wanted to stage a large-scale “spectacular” to counter the British propaganda argument that Republican forces – who had previously fought a guerilla war of ambushes and assassinations – were just a gang of criminal thugs. The problem with his plan was that the IRA was vastly outnumbered, especially in Dublin where the British garrison was about 10,000. In practical terms, guerilla warfare was all the IRA could manage with the resources available at this time.

The Custom House raid might have been less of a military disaster had more thought been given to an exit strategy once the fires had started, by somehow securing a route out of the area, but as it was the Republican forces trying to hold a perimeter were quickly surrounded, ran out of ammunition in the ensuing gun battle, and were overwhelmed. But maybe it really did have a big effect on the British authorities. Just a few months later, on 11th July 1921, a truce was signed and the War of Independence came to an end.

There have been many commemorations today, many of them rightly focusing on the loss of civilian life and lots of coverage in the news and other media. Here is an item that was on RTÉ News last night.

I’m not in Lausanne…

Posted in Biographical, Maynooth, The Universe and Stuff on May 25, 2021 by telescoper

A view of Lausanne, where I am not.

For the rest of this week I shall not be in the beautiful town of Lausanne on the shores of Lake Léman in Switzerland.

The reason I am not in Lausanne is that the Annual Meeting of the Euclid Consortium is being held here this year. I was not in Barcelona for the corresponding meeting last year. At least I have actually been to Barcelona a few times. I’ve never been to Lausanne, and won’t have been even after attending a conference there.

While not in Lausanne I shall be watching the talks remotely from Maynooth but of course there is much more to a conference than the formal sessions. I am looking forward to not travelling there and back as well as not socializing with the other delegates, not sampling the local food and wine, not meeting any new people and not making any use of networking opportunities to start new collaborations. I’ll also not be rummaging around in the conference goody bag.

Above all I am looking forward to not seeing many old friends for the first time in ages and not going out for a drink with them. Instead of that I’ll be not having a drink, on my own, in Maynooth.

These virtual conferences are all very well, and of course made necessary by the Covid-19 pandemic, but what particular annoys me about them is the absence of travel means I don’t get to use my Irish passport. I deeply resent being denied the opportunity brandish it in front of my UK colleagues as I use the fast track at the airport…

Give us a break!

Posted in Biographical, Education, Maynooth on May 24, 2021 by telescoper

Taking a short break from marking exams I thought I’d share an article you can read here entitled Let’s Reclaim Summer Break arguing that Faculty members should make a point of taking a break this summer. Here’s a short excerpt:

Our work seems to have fried our willpower and our ability to unplug and left us feeling tethered to our email and work even when, ostensibly, we are taking time off. We need to rest our minds, bodies and spirits — which will inevitably enrich our ability to return to our work with new energy. We can’t all book a fancy self-care retreat on an isolated island, but maybe it’s time to commit to enjoying a guilt-free beach read. Or to taking a long walk in the middle of the day or visiting a local venue for a live music performance.

I wholeheartedly agree with this. This year has been exhausting enough but I didn’t get any time off at all last summer and it’s definitely showing. I’m completely drained. I can see the tasks piling up for this summer already so I hope I’ve got the willpower not only to say ‘no’ but to disconnect entirely for the time that is owed to me.

But my biggest fear isn’t whether I myself get a holiday this coming academic year or not. It’s that, having worked all summer last year, and put in countless hours of unpaid overtime ever since, there is a real danger that level of overwork will be the “new normal” for all of us – and I don’t just mean at my University.

We’d like to think our employers will let us relax a bit once the Covid19 pandemic is over, but another possibility is that having seen how much we’re prepared to put up with that they’ll expect that to carry on forever, with perhaps a few webinars on “resilience” thrown in for good measure.

Football Round Up

Posted in Football, GAA on May 23, 2021 by telescoper

Well today saw the last round of matches of the English Premier League for this season. The most important match finished Fulham 0 Newcastle United 2. That caps a good end of season run that leaves Newcastle in 12th place having recovered well from an alarming slump in mid-season to avoid any threat of regation.

It’s been a good weekend for Newcastle fans because yesterday Sunderland lost their playoff semi-final against Lincoln City and therefore languish in League One for another season.

Fulham, West Brom were already relegated some time ago, so there wasn’t much end of season drama at the bottom end of the table. I gather that manager Sam Allardyce will be leaving West Brom, having accomplished everything that was expected of him with the club.

As you can see, the top three teams are all from the Midlands. Leicester could have joined them had they not lost to Spurs today so it is Chelsea that joins them in the top 4. Manchester City finish as Champions by a country mile.

By contrast, here in Ireland, the Gaelic Football season has only just started. This afternoon I watched a cracking game between Dublin and Kerry that ended with points level at 4-09 to 1-18 after a late penalty to Kerry allowed them to equalize in stoppage time. Dublin had been well ahead earlier in the game but had to weather a determined fightback to hold on for the draw.

There are no crowds at GAA matches yet but at least one can watch games for free on terrestrial TV…