Caption Competition!

Posted in Biographical, Talks and Reviews, The Universe and Stuff on September 8, 2023 by telescoper

Our roaming photographer took some pictures during my public talk on Wednesday night. This one seems ripe for a caption competition. Please submit your entries through the comments box below:

The Universe from Einstein to Euclid

Posted in Biographical, Talks and Reviews with tags , , on September 7, 2023 by telescoper

As we head into the Day 2 of the ITP2023 I thought I’d share the slides I used for the public talk I gave last night. We had an audience of around a hundred which wasn’t bad given that it is graduation week and the undergraduates aren’t back!

Here is the abstract used to advertise the talk:

Euclid is the name of a new scientific mission from the European Space Agency, launched on July 1st, designed to explore the composition and evolution of the Universe. The Euclid mission takes its name from the ancient Greek mathematician regarded by many as the Father of geometry. Until the last century, Euclid’s theorems were assumed not just to be mathematical notions, but to describe the geometrical structure of the physical Universe. Einstein’s general theory of relativity swept that idea aside and gave us new ways of describing space, by unifying it with time, and by allowing it to be affected by matter in a manner very different from that formulated by Euclid. Over the past century, this theory has proved to be very effective at describing the properties of the Universe as observed by modern astronomical telescopes, while also suggesting the existence of dark matter and dark energy.

The Euclid telescope will create an enormous map of the large-scale structure of the Universe across space and time by observing billions of galaxies out to 10 billion light-years, across more than a third of the sky. Euclid will explore how the Universe has expanded and how galaxies and clusters of galaxies have formed over cosmic history, and how space itself is distorted by these structures.

This talk will discuss our modern ideas of space and time, how the Euclid mission will try to test whether or not they are correct and shed light on the nature of dark matter and dark energy.

And here are the slides:

Obviously I cut a number of long stories very short, which probably contributed to why I had a lot of questions from the audience at the end of the talk. I always assume that’s a basically a good sign because it shows people are interested, but it also makes me worry that I didn’t explain things very well!

We didn’t finish until past 9 o’clock and it was a very warm evening, so I was very happy to have a few pints afterwards in O’Neills…

ITP 2023

Posted in Biographical, Education, Maynooth, The Universe and Stuff on September 6, 2023 by telescoper

So here we are then, first day of the 2023 Irish Theoretical Physics meeting here in Maynooth. It’s a busy schedule for the three days, followed by a little meeting on Saturday to mark the retirement of Brian Dolan

It’s been a busy day for reasons other than the ITP2023 and I’ve left it a bit late to write my talk for this evening’s public lecture so I’d better get on with that this afternoon.

Updates to follow.

The Centre for Astrophysics and Space Science at Maynooth (CASM)

Posted in Maynooth, The Universe and Stuff with tags , , on September 5, 2023 by telescoper

As part of effort to bring about closer interactions between members of the Departments of Theoretical Physics and Experimental Physics at MaynoothUniversity, we have formed a Centre for Astrophysics and Space Science which now has its own web pages.

The members of CASM have been meeting regularly together for coffee on Tuesdays for over a year, during which time more people have joined the Centre.

Today being a nice day we decided to make a team photograph showing staff, postgrads, and postdocs split roughly evenly between the two Departments. There’s also an undergraduate who has been working with us through the summer and helped to set up the web pages.

The People of CASM

Not everyone was able to be there this morning, but it’s lovely to see the group as big as this. I think it will be even bigger when I get back from my sabbatical next year…

September Heatwave

Posted in Biographical, Maynooth with tags on September 4, 2023 by telescoper

What a lovely day to be on sabbatical! It seems that the weather is set fair for a few more days too, which is nice. You don’t often see a satellite image with not a cloud in the sky over Ireland.

It’s cute that the Met Éireann weather map gives a red temperature warning when it’s just 23 °C.

Mind you, it has felt very warm today. So much so that I had a short nap this afternoon. I think of this as training for what I hope will be the regular siesta…

The Higher Education Market

Posted in Education, Maynooth with tags , , , on September 3, 2023 by telescoper
Iontas Lecture Theatre, Maynooth University

Last week I was talking to a current undergraduate student who has been working in the Department of Theoretical Physics over the summer. After a while the conversation turned to the possibilities for postgraduate education. I’ve had that sort of discussion many times over the years with many different students, but the curious thing is that I always find it quite difficult because I’m torn between competing motivations.

On the one hand, there is the wish to have the best undergraduates stay on for further study in the Department. That of course helps our research, but it is also good for our finances as postgraduate students bring income. I think we offer good opportunities at both Masters and Doctoral levels, so it’s not too difficult to point these out to students in a way that at least some find persuasive.

On the other hand, there is the fact that I am an academic not a salesman and I feel that it is my responsibility to give honest guidance. The fact is that a good undergraduate degree from the National University of Ireland will open a lot of doors elsewhere, and these should be considered. At Masters level in particular, there are excellent courses available in the EU which have the advantage of not charging fees at the level they are charged in Ireland. Add to that the cost of living and accommodation crises. It’s no surprise that many of our graduates seize opportunities to go to postgraduate study in Germany, Denmark or The Netherlands (to name just a few). I have no problem with explaining the advantages of options outside my own Department and no doubt some students find these points persuasive too.

There’s a wider context for this type of dichotomy, namely the progressive marketisation of higher education. When it comes to recruiting undergraduate students we academics are increasingly required to act as reps for the University, hawking our wares at Open Days, Recruitment Fairs, and a variety of online events. I’m reasonably happy to participate in these when asked to do so, but I always take the approach of describing what we do in our Department rather than trying to do down what happens elsewhere. I’m an academic not a salesman. And I work in a public university, not a private business. I see my job as giving advice in as objective a way as possible. If I feel that our courses would not be the right choice for a student, I’ll explain why. In the end, of course, the decision is up to the student, but I feel obliged to give them enough information to make an informed choice.

A couple of years ago, the (then) new President of Maynooth University walked up to the Theoretical Physics stand at a Maynooth Open Day when I was on duty. The first thing she said was “Sell your course to me”. I described what we had on offer, but I don’t think what I said impressed her at all. We can only hope to succeed in recruiting students who have some interest in science. An Open Day is a bit late to cultivate that: interest has to be nurtured from an early age.

Another problem I find, speaking as a physicist (though this is probably also true for people in many other disciplines), is that we see physicists in other institutions as colleagues rather than business rivals. This is particularly true for those of us working in large consortia that spread over many departments (and indeed many countries). I therefore see myself as a physicist who happens to work at Maynooth University rather than as an employee of Maynooth University who happens to do physics. It’s not that I am disloyal to my employer, it’s just that I have a greater loyalty to a larger community.

I do understand that the reality of the funding system here means that we have to be able to recruit students in order to pay our way, but I feel that the way to achieve that is by establishing a strong reputation in our core academic mission of teaching and research rather than through marketing gimmicks, corporate branding, or other forms of commercial flummery. No amount of propaganda will disguise a higher education institution that neglects those things that higher education is about.

Fall – Bridget Riley

Posted in Art with tags , , on September 2, 2023 by telescoper
Fall 1963 Bridget Riley born 1931 Purchased 1963 http://www.tate.org.uk/art/work/T00616

by Bridget Riley (1963, 1410 × 1403 mm, polyvinyl acetate paint on hardboard, Tate Britain, London, UK)

The gallery label reads:

‘I try to organise a field of visual energy which accumulates until it reaches maximum tension’, Riley said of this work. From 1961 to 1964 she worked with the contrast of black and white, occasionally introducing tonal scales of grey. In Fall, a single perpendicular curve is repeated to create a field of varying optical frequencies. Though in the upper part a gentle relaxed swing prevails, the curve is rapidly compressed towards the bottom of the painting. The composition verges on the edge of disintegration without the structure ever breaking.

The Sabbatical Starts Here…

Posted in Biographical, Maynooth with tags , on September 1, 2023 by telescoper

Today is 1st September 2023, which means that it is the first day of my year-long sabbatical. No teaching and no admin until 31st August 2024! I moved the last of my personal things out of the office yesterday and put an auto-reply on my email. I did plan to take today off to celebrate but I had some things to do relating to the Open Journal of Astrophysics so I spent the morning doing them. If the rain holds off I might do a spot of gardening later on.

A sabbatical isn’t a holiday of course, and will have plenty to do over the next year, much of it clearing a backlog of things I should have done well before now but failed because of workload issues. I make no apology for taking the first day off, however.

Next week will be quite busy. I will be attending a meeting in Maynooth next week and giving a public talk, which gives me the chance to post a reminder that it’s not too late to register for either/both:

Another thing I did last night was to deactivate my own personal Twitter account as well as the one for the Open Journal of Astrophysics. Twitter is both unpleasant and useless these days and I can’t be doing with it anymore. I had been on it for 14 years and had accumulated over 7,000 followers. Those that want to carry on following me on social media will find me on BlueSky or Mastodon. The same goes for those who followed the Open Journal of Astrophysics on Twitter.

Anyway, in a fortnight or so I should be heading off to distant lands. I’m greatly looking forward to getting away and being able to concentrate on things to do with research for a change. I’m looking forward to the temporary change of location, not least because a warmer climate might help with my arthritis…

Times of Offers

Posted in Education, Maynooth with tags , , , , on August 31, 2023 by telescoper

It’s that time of year again when I break with the self-imposed tradition of not buying a newspaper during the week. I don’t usually buy a newspaper during the week but today is the day the full set of CAO points required for different courses across the land are published in the print edition of the Irish Times, about ten days earlier than last year. This is of course just the first round of offers so things may change over the next week or two.

Students now have to decide whether to accept their first-round offer or try to change course. Departments won’t know how many new students they have for a while yet.

The official low-tech results for Maynooth (in the lower right of the page shown above) are here. Minimum points required for Maynooth’s most important course, MH206 Theoretical Physics and Mathematics, are 494 this year, down a little from 510 last year. MH201 General Science is 350 this year compared to 400 last year; MH204 Physics with Astrophysics is 376 this year, down from 423 last year. MH101 General Arts – the most popular course at Maynooth and indeed in all Ireland – has a first round offer of 310 this year, down from 338 last year.

In fact, most courses I have looked at, not only at Maynooth, have lower first-round offers this year than last year. This is confirmed by this news item which says:

In more good news for this year’s applicants, there has been a fall in the points requirement for more than 60% of Level 8 courses.

This is interesting because it contrasts with news stories about grade inflation at the Leaving Certificate. How does one reconcile the fact that a majority of courses are asking for lower points, when the average points are going up? I think part of the answer lies in the fact that the CAO points needed for a course is largely about demand versus capacity rather than academic performance. For the last few years Maynooth University has been recruiting more and more students, putting pressure on accommodation, teaching loads and campus space. It seems likely that the desire to keep this trend going is at least part of the reason for the large falls in CAO points here. This is probably happening to some extent across the sector, though Maynooth has a more urgent need for more students – to pay for the legions of new managers it has appointed.

Another part of the answer is that one subject in which grades have fallen this year is Mathematics, specifically Higher Mathematics. Mathematics is a core subject for the Leaving Certificate and it therefore has the potential to have an effect across the board. A fall in the top grades at Higher Maths will propagate downwards through many subjects.

Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , on August 30, 2023 by telescoper

Not unexpectedly because of holidays, August has been rather a quiet month at the Open Journal of Astrophysics, but with people returning to work this week business has picked up again and it’s time to announce the last batch (all published this week).

In fact, this week we have published three papers, which I now present to you here. These take the count in Volume 6 (2023) up to 34 and the total published by OJAp up to 99. Who will be the author(s) of the 100th? We will just have to wait and see! I’ll do a special post for whichever paper wins that honour.

In chronological order, the three papers published this week, with their overlays, are as follows. You can click on the images of the overlays to make them larger should you wish to do so.

First one up is “Bright common envelope evolution requires jets” by Noam Soker of Technion, Haifa in Israel. This is a discussion of the role of jets that a main sequence secondary star launches as it enters a common envelope evolution (CEE) with a primary giant star. The paper was published on 28th August, is just the fifth item in the folder marked Solar and Stellar Astrophysics and can be found here.

Here is a screen grab of the overlay, which includes the abstract:

 

You can find the officially accepted version of the paper on the arXiv here.

The second paper to announce is “Almanac: MCMC-based signal extraction of power spectra and maps on the sphere” by Elena Sellentin (Leiden), Arthur Loureiro (Stockholm); Lorne Whiteway (UCL); Javier Lafaurie (Leiden); Sreekumar Balan (UCL); Malak Olamaie (York); and Andrew Jaffe & Alan Heavens (Imperial).  This presents a new software tool called Almanac , which uses Hamiltonian Monte Carlo sampling to infer the underlying all-sky noiseless maps of cosmic structures, together with their auto- and cross-power spectra.

This one is  in the folder marked Cosmology and Nongalactic Astrophysics. The paper was also published on 28th August 2023 and you can see the overlay here:

 

The accepted version of this paper can be found on the arXiv here.

The last paper of this batch paper is in the Instrumentation and Methods for Astrophysics folder. It is entitled “Neural Network Based Point Spread Function Deconvolution For Astronomical Applications” and the authors are: Hong Wang, Sreevarsha Sreejith, Yuewin, Nesar Ramachandra*, Anze Slosar & Shinjae Yoo, all of the Brookhaven National Laboratory (NY) except * who is at the Argonne National Laboratory (IL), all based in the USA. This paper discusses a neural-network based deconvolution algorithm based on Deep Wiener Deconvolution Network (DWDN) and its performance in an astronomical context.

Here is the overlay:

 

You can find the full text for this one on the arXiv here.