Archive for the Maynooth Category

« Older Entries
Newer Entries »

M.C. Escher and CP Violation

Posted in Art, Maynooth, The Universe and Stuff with tags , , , on April 28, 2026 by telescoper

I’ve had these pictures for quite a while and can’t remember where I got them from, but I used to show them in my lectures on Theoretical Particle Physics when I was in Nottingham to illustrate CP-violation and used them in this morning’s lecture at Maynooth.

The following picture by M.C. Escher is called Day and Night:

If you look at it you can see two kinds of symmetry emerging. One is a kind of reflection symmetry about a vertical axis drawn through the centre of the picture that applies to shapes but not to colour. The other is between black and white. But it is obvious that the picture doesn’t display these symmetries separately: to get a picture unchanged from the original you would have to do the mirror reflection and change black to white (and vice-versa).

The mirror reflection in the image can be taken to represent parity (P). Strictly speaking parity refers to a reflection through the origin in 3D rather than a mirror reflection, but it’s just for illustration. We know that a parity symmetry is violated in weak interactions just as it is in the picture.

The other possible symmetry, between black and white can be taken to represent charge-conjugation (C), the operation that converts particles into anti-particles and vice-versa.

While P is not an exact symmetry of weak interactions, it was long thought that the combination of C and P (CP) would be. Actually it isn’t. The story of the discovery of CP-violation is fascinating but I don’t have time to go into it here. It suffices to say that the Escher print also displays CP violation.

First lets do `C’, i.e. convert black to white and vice-versa. The result is:

Now reflect about the vertical mid-line to illustrate `P’:

If `CP’ were an exact symmetry then that image would be identical to the original, which I reproduce here:

You can see, however, that while some elements of the picture do look the same after this combined operation (e.g. the birds), others (e.g. the buildings at the bottom) do not. Although CP is not an exact symmetry of this picture, it is almost (just like it is in particle physics).

7 Comments »

Two Weeks To Go…

Posted in Biographical, Education, Maynooth with tags , , , on April 27, 2026 by telescoper

There are just two weeks of teaching left in the Spring Semester at Maynooth University. Actually slightly less than that because next Monday (May 4th) is another bank holiday. That day doesn’t make any difference to my own teaching, however, as I have no teaching sessions on Mondays anyway.

As I mentioned last week, the formal teaching part of one of my modules (Computational Physics) is already over and the students are now – or should be – busy doing mini-projects.

My other module, Particle Physics, has four remaining lectures. That means that I’m on schedule, despite missing one lecture on Good Friday. The very last lecture for this module is on the last day of term, May 8th, so I don’t know how many students will be there. Come to think of it, because this is a final-year module, it may actually be the last lecture of all at Maynooth for some students…

The end of teaching does not mean the end of the term, however. We have a short “break” and then, on May 15th, the examinations start. In the break I’ll have to mark a stack of Computational Physics projects. That’s always quite hard work as I have to run the codes and check the results as well as read and grade the written reports.

This week and next we also have the final presentations for project students. That will take up two whole full afternoons (this Wednesday and next Wednesday). There’s usually a bit of a do after these to give the students a send-off, as these are projects done by the graduating class. I have been supervising two students this year, plus an MSc student (though the latter will not finish until August).

People sometimes ask me why we have such heavy teaching loads at Maynooth University. Four modules a year – other staff do five (as I did a few years ago when was also Head of Department) – plus projects is far more than one would expect of a “research-led” University outside Ireland. Part of the reason is what I mentioned yesterday – that the University (along with most others) spends far too much of its income on Management salaries and projects that have nothing to do with research or teaching. Other than that I can’t comment. According to this document, Maynooth University has committed to

Introduce a University Workload Allocation Model (WAM) enhancing transparent processes and procedures in the allocation of work.

If there is such a model, it is news to me…

P.S. There’s an even older document here (dated 2014) that says:

The University is committed to ensuring that the allocation of work is reasonable and fair across and within academic units. It is also required to exercise oversight of the implementation of academic workload management. In support of this, the Head of Department / School / Institute will monitor and record workload allocations and will provide to the university, via the Faculty Dean, an annual report on the procedure and model used to allocate workloads, and also an anonymised summary of the average and range of workload distributions between teaching, research and service among all academic staff in the Department/School/Institute.

The design and implementation of workload allocation models will be undertaken by Departments/Schools/Institutes in accordance with the general principles outlined above.

Will it? When?

Leave a comment »

The Sharp End of Term

Posted in Biographical, Education, Maynooth with tags , , , on April 23, 2026 by telescoper

So here I am, sitting in the (empty) Physics Computer Lab. The formal Computational Physics lab sessions are over, but I’m on duty to provide help the students with their project work, which will take up the remaining two-and-a-bit weeks of term. It’s a lovely day outside which explains why there are very few people in the lab, and none of them have asked for help so I’ve been busy getting on with some work. Past experience with these sessions suggests that they’ll all come just before the project deadline, which is May 8th.

Up until last week I had a Computational Physics lecture at 9am on Thursdays, but the last one of those happened last Thursday. It was nice to have a more leisurely start this morning. I did think I might get a haircut on the way to work but when I passed my usual barber’s I saw it was full of people waiting their turn so I walked on. It seems that the good weather gave quite a few people the same urge to have shorter hair.

Yesterday was the last Class Test for my other class, Particle Physics, and I’ve taken the opportunity to correct all the scripts for that. I even had time to type up the solutions all neatly and tidily in Latex (including doing Feynman diagrams, which is fun).The end of that job means no more grading for that module until the main examination, which is about a month away. I do however, have lectures and tutorials still to do, including two at 9am on Tuesdays.

The finest weather is usually reserved for the exam period, of course, to maximize the annoyance of students. In my memory all my undergraduate examinations took place in very fine weather, with the exception of my Physics practical the night before which there was an enormous thunderstorm. Come to think of it, that could well have been a portent that warned me off experiments and made me become a theorist.

2 Comments »

Maynooth University Library Cat Update

Posted in Maynooth with tags , , , on April 22, 2026 by telescoper

This week at Maynooth University numerous parties of schoolkids have been, and are being, shown around the campus. Naturally an important stop on this tour is the abode of Séamus the Library Cat. The weather has been nice this week so far, as it was today, so said feline has generally been out and about and making himself available to be admired. On my way to lunch I managed to bypass a large coach party of schoolgirls and reach the cat’s spot ahead of them. I found Séamus giving himself a good wash and brush-up in anticipation of the arrival of the visitors.

Leave a comment »

The Perseus Cluster

Posted in Euclid, Maynooth, The Universe and Stuff with tags , , , , on April 16, 2026 by telescoper

In a vain attempt to convince my readership that I know anything about observational astronomy, I thought I’d share this image of the central regions of the Perseus Cluster (also known as Abell 426) made by my final-year project students:

Picture Credit: Ben Doyle

The image was taken last November using the 1.20m reflecting telescope at the Observatoire de Haute-Provence where the final-year astrophysics students from Maynooth spent a week last November on a field trip taking various observations. The exposure was 240 seconds and the field of view is about 15 arcminutes on a side. Most of the objects in the image are galaxies, rather than stars.

I asked my students to look at this cluster (which is about 10 degrees across), partly because it appears near the Zenith in November so would be a good target, partly because it is nearby so the galaxies in it are therefore quite bright, and partly because it was observed by Euclid and featured among the Early Release Observations. The Euclid telescope is also 1.20m in diameter, but because it has a very fancy camera and is in space, Euclid reveals far more galaxies but I was nevertheless impressed at how well this turned out!

Leave a comment »

Back for the Last Four Weeks…

Posted in Biographical, Education, Maynooth with tags , , , on April 13, 2026 by telescoper

So the Easter break is over and I was back to campus today armed with a very long to-do list. I’m pleased to say I’ve ticked all the items off except the last, which was to prepare my lecture for 9am tomorrow. I’ll do that after supper.

I was very tired this morning after doing a bit of gallivanting for a couple of days. Am I too old to be carrying on like that? Yes. Do I intend to stop? No. Although I had a lot to do I didn’t have any lectures or tutorials so I was able to knuckle down and get on with things, interrupted only by an obligatory telecon.

We have four weeks left until the end of lectures for Semester 2. To be precise it’s four weeks minus one Bank Holiday (on Monday 4th May) which makes it 3.8 (working) weeks, but I don’t have lectures on Mondays so this isn’t very relevant to me. My Particle Physics module will continue in the same vein until the end of teaching but Computational Physics changes after this week, with lectures and formal lab sessions ending allowing the students time to do their mini-projects (which they have already started). They will still have access to the labs and be able to consult the demonstrators for help on their projects, though they can work at home (or somewhere else) instead if they prefer.

Other signs of the approaching end of term is that the May Examination timetable has been published, the required papers are being printed, schedules of student presentations are being circulated, and arrangements being made to mark projects.

When teaching is over for the academic year , and before exam marking starts, assuming a whole day of decent weather arrives, I plan to walk from Maynooth into Dublin along the Royal Canal. That’s a distance of 27 km. I do intend to walk the length of the National Famine Way later this year, but I was convinced to do one stage first to see if my knees can take it. The final leg of the Famine Way is from Maynooth to Dublin, which is convenient because if I’m forced to give up I can easily get the bus or train home, as I can if I reach the end.

Now for a quick supper, write my lecture for tomorrow morning, and have an early night!

2 Comments »

An independent arXiv

Posted in Finance, Maynooth, Open Access with tags , , , on April 9, 2026 by telescoper

I’m a bit late passing this news on, but a few weeks ago arXiv announced that from 1st July 2026 it will be establishing itself as an “independent nonprofit organization”. It has been hosted for many years by Cornell University. You can read here about the reasons for this and how it will work, and there is a lengthier article in Science magazine, but the quick summary is

This transition allows for faster technological development, greater organizational flexibility, expanded partnerships, and long-term financial sustainability. A platform built by scientists for scientists, the new arXiv will continue to serve researchers worldwide with the same dedication to free and open scientific discovery.

Such a move creates opportunities, but also carries risks. The sustainability of the new-look arXiv will depend on finding appropriate sources of income, for example. I wish arXiv well in this move. There’s an advertisement for the post of Chief Executive, if anyone fancies the job!

One possible future model for the Open Journal of Astrophysics is as a standalone non-profit organization of some sort, funded also by donations. Currently we are funded by the Library at Maynooth University, where I am based. Having made the decision not to charge fees of any kind, we lack any source of income other than the University. I am very grateful for that support, but we are run on a very tight budget. We keep costs to an absolute minimum, but are not free.

I have written before about what I think the future of Diamond Open Access could look like. I would like to see a range of Diamond Open Access journals offering a choice for authors and serving different sub-disciplines. Most universities nowadays have publishing operations so there could be network of federated journals, some based on arXiv and some based on other repositories and others with different models, such as SciPost. Perhaps institutions are worried about the expense but, as we have shown the actual cost, is far less than they are wasting on Article Processing Charges.

Everything is working well right now at OJAp, but it is not reasonable that the expense of running a journal that serves the global astrophysics community should fall entirely on one small University in Ireland. It won’t be sustainable in the long run, either, if we continue to grow at the present rate. Compare us with the Diamond Open Access publisher SCIPOST, which has a long list of sponsors covering its costs; we have none. My only hope at the moment of turning OJAp into an independent organization is to win the lottery!

Another thing makes me nervous. Many modern universities, which are nominally non-profit institutions, are managed by people who care far more about revenue generation than about academic scholarship and research. I worry that someone upstairs might pressurize us to introduce charges to generate income by threatening to close us down.

I know that money is very tight in astrophysics these days but if you have access to any potential sources of funding – then please consider supporting OJAp!

1 Comment »

Winding Down for Easter

Posted in Biographical, Education, Maynooth with tags , , , on April 2, 2026 by telescoper

When I was a lad, back in England, the name for the Thursday before Good Friday was Maundy Thursday. That term isn’t used here in Ireland, where it seems to be known as Holy Thursday. Anyway, Maynooth University is closed tomorrow (Good Friday) but not today (Holy Thursday). Although today is not an official holiday, some campus facilities are in fact closed – including Pugin Hall, where I often have lunch. This helped me plan my activities for the day.

My agenda for Holy Thursday included:

  • giving a 9am Computational Physics lecture;
  • grading the submissions from the last Computational Physics lab test and writing feedback;
  • meeting with my masters project student;
  • supervising a computer lab session,;
  • meeting with my undergraduate project student;
  • going home, and collapse in a state of exhaustion.

To get to the last item as quickly as possible, I decided my strategy to make use of the lack of availability of food on campus would be to work all the way through lunch to get my grading done.

On the way to campus for the first item on the agenda I noticed how quiet the town was this morning. The schools are on holiday this week and next so there was no school run. The lack of people was even more noticeable when I got to campus, with many fewer students than usual, even at 8.45am. I did consider the possibility that nobody might appear for my lecture, but in the end I had about 30% of those expected. That’s a disappointing number but I gather it’s a better attendance than some of my colleagues got today. When I finished at about 10am, I walked back to my office through a still very quiet North campus.

As usual happens in a day’s work, there were quite a few interruptions – mainly to do with postgraduate matters – but I managed to do all my corrections ahead of the lab this afternoon. I also had my two project meetings, just to keep up-to-date before the break next week. It’s a stressful time for students as we approach the end of the academic year, so I advised them to make sure they book took at least a bit of time off to regroup for the final push and the submission of their reports.

Anyway, I’ve now ticked off every item on my to-do list except the last and will shortly make my way home to complete the job.

1 Comment »

The Hitchhiker’s Guide to the Swampland Published

Posted in Maynooth, The Universe and Stuff with tags , , , , , on March 31, 2026 by telescoper

Regular readers of this blog might remember that last year I did a post about a very comprehensive review article which had appeared on arXiv with the title Hitchhiker’s Guide to the Swampland: The Cosmologist’s Handbook to the string-theoretical Swampland Programme. The article is by Kay Lehnert (who happens to be my PhD student). Well, that paper was published last Saturday (28th March 2026) in the journal Fortschritte der Physik (which I translate roughly as “Advances in Physics”, but whose official English title seems to be “Progress of Physics”). Anyway, it is available (and indeed openly accessible) here. And, if you don’t believe me, here’s a grab of the front page showing the deets (as you young people say):

5 Comments »

Ahead of a Four-Day Week…

Posted in Artificial Intelligence, Biographical, Education, mathematics, Maynooth with tags , , , , , , on March 29, 2026 by telescoper

It’s Sunday 29th March – Palm Sunday in fact – and Friday 3rd April is Good Friday, which is followed by a break of a week for Easter, so I’ve been looking at what I have to do in the four days between Monday and Thursday.

On Tuesday afternoon part of my 3rd Year Computational Physics class will be doing a supervised test in the computer lab. I (foolishly) promised to ensure they would get their grades before Easter, so I’m going to have to mark them straight away. This is a larger group than usual because some students who would normally be in the lab on Thursdays swtiched to Tuesday so they could go on a trip to Armagh. Anyway, this is the third lab test and at least I have graded the first two tests for all groups in time for the arrival of the new ones.

There will be one more of these lab tests after the Easter break but after that the students will be working full-time for 3 weeks or so on mini-projects. That is the part they usually enjoy most and I’m very happy to see that some have already started work.

Then, on Wednesday I have the second class test for my 4th year Particle Physics module. This is the second such test, and it will be held during a tutorial session. This is a pen-and-paper test rather than a coding test to be done in the lab. For such tests I allow students to bring whatever they like on paper but phones, laptops and tablets are banned. This is the easiest way I could think of to avoid students using AI to solve the problems. In previous years I gave take-home assignments for this module, and I still hand out exercise sheets to be gone over in tutorials, but these are for formative purposes only. The summative assessments are the class tests. There will be three of those, which means they will have to endure one more after Easter. In a normal week I would have a Particle lecture on Friday, but that won’t happen because it’s Good Friday and my lectures apparently aren’t good enough to happen on that day.

As well as the Computational Physics lab test and the Particle Physics class test, next I have two lectures, both at 9am – one on Tuesday and one on Thursday – and another lab session on Thursday which is not a test, but a practical session about solving ODEs.

Then it will be the Easter Break. After that, according to my calculations, there will be four more teaching weeks before the examination period. The last day of teaching is May 8th. Between that and the examinations there is a gap of a week during which I will have to mark all the completed Computational Physics project reports, as well as giving some revision classes if there is demand for them.

Leave a comment »

« Older Entries
Newer Entries »