Today is another anniversary. I just received the following message from WordPress.com reminding me that today is the 18th anniversary of my registration with them, which is when I took my first step into the blogosphere. That was way back on 15th September 2008…
I suppose this means that this blog is an adult now!
I actually wrote my first post on the day I registered but, unfortunately, I didn’t really know what I was doing on my first day at blogging – no change there, then – and I didn’t actually manage to figure out how to publish this earth-shattering piece. It was only after I’d written my second post that I realized that the first one wasn’t actually visible to the general public because I hadn’t pressed the right buttons, so the two appear in the wrong order in my archive. Such was the inauspicious beginning of this “shitty WordPress blog”!
Since then I have published 7,846 blog posts posts (including this one), which have altogether received over 6.1M page views from 2.6M unique visitors. That doesn’t include the 2000+ subscribers who receive posts by email nor those who view the federated version via the fediverse. The largest number of hits I have received in a single day is still 8,864 (in 2014, at the peak of the BICEP2 controversy).
Today is the 40th anniversary of the publication of my first ever scientific paper!
Here is the front page:
This was before the days of arXiv so there isn’t a copy on the preprint server, but you can access the whole article here on NASA/ADS.
All right. I know it’s a shitty little paper. But you have to start somewhere!
I’m particularly sad that, looking back, it reads as if I meant to be very critical of the Kaiser (1984) paper that inspired it. I still think that was a brilliant paper because it was based on a very original idea that proved to be enormously influential. The only point I was really making was that a full calculation of the size of the effect Nick Kaiser had correctly identified was actually quite hard, and his simple approximation was of limited quantitative usefulness. The idea was most definitely right, however.
I was just a year into my PhD DPhil when this paper came out, and it wasn’t actually on what was meant to be the subject of my thesis work (which was the cosmic microwave background), although the material was related.
This paper provides two excellent illustrations of what a good supervisor John Barrow was. I was a bit stuck with the project that John had assigned me and eventually admitted to him that I was having problems getting anywhere. I thought he’d assume I was useless and suggest that someone else should supervise me. But no. He said he realised it was a hard problem and sometimes it’s good to think about something else when you’re stuck. So he asked me to look at cluster clustering for a bit. I told him what I found and he said I should write this up as a paper, which I did. Most importantly however the trick I used in simplifying the calculations in this paper turned out to be applicable to the first problem, hotspots in the cosmic microwave background, which led a success in the project and to my second paper. We were both delighted that everything turned out well with that original project.
My original draft of this first paper had John Barrow’s name on it, but he removed his name from the draft (as well as making a huge number of improvements to the text). At the time I assumed that he took his name off because he didn’t want to be associated with such an insignificant paper, but I later realized he was just being generous. It was very good for me to have a sole-author paper very early on. I’ve taken that lesson to heart and have never insisted on putting my name on my students’ work.
What we call the beginning is often the end And to make and end is to make a beginning. The end is where we start from.
from Little Gidding, Four Quartets, by T.S. Eliot.
The start of teaching for 2026/7 is approaching at an alarming rate. new and continuing students are registering and today we had a staff meeting in the Department of Physics about arrangements for the new term. This all made me think again about retirement.
About three years, while I was in Barcelona on sabbatical , I posted an item about looking forward to retirement. Here is an excerpt from that piece:
The fact of the matter is, though, that I can’t afford to retire yet. I have a mortgage to pay and I’ve only had five full years of pensionable service in the Irish system, so won’t get much of a pension. I have the frozen residue of my UK pension, of course, but that is subject to an actuarial reduction if I take the benefit before I’m 65, which is also the standard retirement age for academic staff in Ireland. I can’t be made to retire here until I’m 70, in fact, but I think I’ll be well beyond my best-before date by then and am not keen to overstay my welcome.
So it looks like I’ll have to stay until I’m 65 at the earliest. In fact I won’t be able to collect the State Pension (SPC) until I’m 66, so I’ll probably have to stay until then. That means that when I get back from sabbatical I will have four or five years left until I can retire.
Since I posted this I made a firm decision that I will retire as soon as I’m able, which should be in June 2028. Having sold my old house in Cardiff some time ago, I have paid off my Maynooth mortgage which makes the financial situation much simpler. I am now quite confident that I can afford to retire before I’m 66.
I know many academics don’t like the idea of retiring. I suppose that’s because they’re afraid they won’t know what to do with their time. I’ve never felt like that. I’ve always had plenty of outside interests, but now there’s another factor. As I alluded to in an earlier post, and contrary to all my expectations of three years ago, there is another person involved. That person, whose name I won’t reveal, graduated this summer from an unnamed university, and is just about to embark on a two-year Masters degree (in a subject not to be disclosed) in a location I won’t tell you about. He will be finishing that course in the summer 2028.
For the next two years things for us will be pretty much as they are now: not living together, but spending as much time in each other’s company as possible at weekends and holidays. That arrangement suits us both very well in the current circumstances but we have already started discussing plans beyond the two-year horizon. Some of these are not at all serious, but amusing to think about. Others would be fantastic if they turned out to be possible. We have the best part of two years to decide what to do. In any event, I find it exciting to be able to think seriously of retirement as a beginning as well as an end.
I couldn’t resist posting these two hilarious pictures of Donald Turnip’s visit to the Áras an Uachtaráin in Phoenix Park yesterday to meet the President of Ireland, Catherine Connolly. Her expression in the first picture is priceless, and the second one looks like she sent him away with a flea in his ear.
It seems that Trump said that he “would love to see” a united Ireland, which is quite a surprising statement to come from an Orange Man…
I did a post a few months ago about Space Warps, a new citizen science project on the Zooniverse platform, in which volunters can search to find rare and elusive strong gravitational lenses in never-before-seen images captured by the European Space Agency’s Euclid space telescope. The project aims at shining a light on dark matter in galaxies and providing clues about the mysterious thing call dark energy.
The Space Warps Euclid project is entering the closing stages, but there is still about a week in which you can help with refining the final sample. Read more about it here:
It’s time once more for another Saturday update of activity at the Open Journal of Astrophysics. Since the last update we have published a further seven papers, bringing the number in Volume 9 (2026) to 202 and the total so far published by OJAp up to 649. This means that the total in Vol. 9 (2026) has now passed that of Vol. 8 (2025), with more than three months to go.
I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also contain a clickable form of the DOI for each paper. Our Mastodon account has regular updates and other announcements from OJAp too.
The first paper this week was published on Monday 7th September in the folder Astrophysics of Galaxies. The title is “Not all cores are equal: Phase-space origins of dynamical friction, stalling and buoyancy” and the authors are Shashank Dattathri & Frank C. van den Bosch (Yale U., USA), Uddipan Banik (Princeton U., USA), Martin Weinberg (U. Mass., USA), Priyamvada Natarajan (Yale U., USA), Zhaozhou Li (Nanjing U., China) and Avishai Dekel (The Hebrew U., Israel). The paper describes how the distribution function of a galaxy, not just its central density gradient, influences the efficiency and direction of dynamical friction, affecting the movement of massive objects within it.
The overlay is here:
You can find the officially accepted version on arXiv here and the announcement on Fediverse here:
New Publication at the Open Journal of Astrophysics: "Not all cores are equal: Phase-space origins of dynamical friction, stalling and buoyancy" by Shashank Dattathri & Frank C. van den Bosch (Yale U., USA), Uddipan Banik (Princeton U., USA), Martin Weinberg (U. Mass., USA), Priyamvada Natarajan (Yale U., USA), Zhaozhou Li (Nanjing U., China) and Avishai Dekel (The Hebrew U., Israel)
The second paper for this week, also published on Monday 7th September, but in the folder Earth and Planetary Astrophysics, is “The Third Option: Color Phase Curves to Characterize the Atmospheres of Temperate Rocky Exoplanets” by Drake Deming (U. Maryland, USA) and 8 others based in the USA, Germany and The Netherlands. This article presents a A spectroscopic survey of the Carousel lens galaxy cluster, identifying 12 lensed sources and 57 unlensed field galaxies. The findings could help constrain cosmological parameters and cluster properties.
The overlay looks like this:
The official version of the paper can be found on arXiv here and the Fediverse announcement here:
New Publication at the Open Journal of Astrophysics: "The Third Option: Color Phase Curves to Characterize the Atmospheres of Temperate Rocky Exoplanets" by Drake Deming (U. Maryland, USA) and 8 others based in the USA, Germany and The Netherlands.
The third paper of the week, also published on Monday 7th September but in the folder High-Energy Astrophysical Phenomena, is “Dependences of radio pulsar parameters on the kick velocity” by Anton D. Lazarev and Sergei B. Popov (Moscow State U., Russia). This study analyzes the velocity kick of neutron stars, finding that 23% belong to the low-velocity mode. Differences in magnetic field distribution emerge, but no significant bimodality in physical parameters.
The overlay is here:
The official version of the paper can be found on arXiv here and the Fediverse announcement here:
New Publication at the Open Journal of Astrophysics: "Dependences of radio pulsar parameters on the kick velocity" by Anton D. Lazarev and Sergei B. Popov (Moscow State U., Russia)
The fourth paper of the week is “A Dusty Quenching-Candidate AGN host at z=5.7: massive quiescent galaxies may quench already during the dust-obscured phase” by Francesco D’Eugenio (U. Cambridge, UK) and 14 others from the UK, Italy, China and The Netherlands. It was published on Wednesday 8th September in the folder Astrophysics of Galaxies. This article concerns RUBIES-EGS-9809, a dust-reddened galaxy with a dominant point-source component, suggests that AGN feedback may influence its host., indicating that massive galaxies can host evolved stellar populations during their dust-obscured phase.
The overlay is here:
The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:
New Publication at the Open Journal of Astrophysics: "A Dusty Quenching-Candidate AGN host at z=5.7: massive: quiescent galaxies may quench already during the dust-obscured phase" by Francesco D'Eugenio (U. Cambridge, UK) and 14 others from the UK, Italy, China and The Netherlands.
The fifth paper of the week is “The Carousel Lens I: A Spectroscopic Survey of the Carousel Lens Field” by Jackson H. O’Donnell (U.C. Santa Cruz, USA) and 22 others from around the world. This was published in the folder Astrophysics of Galaxies on Thursday 10th September 2026. This paper presents a spectroscopic survey of the Carousel lens galaxy cluster, identifying 12 lensed sources and 57 unlensed field galaxies. The findings could help constrain cosmological parameters and cluster properties.
The overlay for this one looks like this:
The officially-accepted version of this paper is on arXiv here and the Mastodon announcement on the fediverse here:
New Publication at the Open Journal of Astrophysics: "The Carousel Lens I: A Spectroscopic Survey of the Carousel Lens Field" by Jackson H. O'Donnell (U.C. Santa Cruz, USA) and 22 others from around the world.
The penultimate, sixth, paper of the week is “No Gravitational Anomaly in Wide Binaries from Forward Modeling of 3D Orbits” by Serat M. Saad and Yuan-Sen Ting (Ohio State U., USA). This was also published on Thursday 10th September, but in the folder Solar and Stellar Astrophysics. The study reanalyzes a dataset on gravitational anomalies, finding results consistent with Newtonian gravity, contrary to previous findings that suggested Modified Newtonian Dynamics. The overlay for this one is here:
The officially accepted version is on arXiv here and the Mastodon announcement here:
New Publication at the Open Journal of Astrophysics: "No Gravitational Anomaly in Wide Binaries from Forward Modeling of 3D Orbits" by Serat M. Saad and Yuan-Sen Ting (Ohio State U., USA)
Last but by no means least we have “The quenching time and timescale distribution of z~2 quiescent galaxies from precise colour distribution analysis” by Vivienne Wild (U. St Andrews, UK), Ho-Hin Leung & Adam Carnal (U. Edinburgh, UK) and Maya Skarbinski (Johns Hopkins U., USA). This paper was published on Thursday 10th September in the folder Astrophysics of Galaxies. It describes a study that uses simulation-based inference to analyze galaxy formation and quenching times, revealing that galaxies must quench rapidly post-Big Bang to achieve a specific color distribution.
The overlay is here:
The final version of this paper is on the arXiv here and the Mastodon announcement here:
New Publication at the Open Journal of Astrophysics: "The quenching time and timescale distribution of z~2 quiescent galaxies from precise colour distribution analysis" by Vivienne Wild (U. St Andrews, UK), Ho-Hin Leung & Adam Carnal (U. Edinburgh, UK) and Maya Skarbinski (Johns Hopkins U., USA)
It is worth mentioning that there was one deferred arXiv mailing this week, due to the Labor Day holiday in the USA, so some papers were therefore published a day later than usual.
That concludes this week’s update. I’ll do another next weekend.
As a journal Editor I’ve been grappling with the problem of a huge influx of papers that use various forms of generative AI. As I’ve said before the problem seems to me not that competent scientists use LLMs and the like to speed up their work, but that fools can use them to produce superficially plausible but scientifically flawed articles very quickly. It’s the latter category that comprises much of the increase at the Open Journal of Astrophysics. I’d be far more positive about LLMs if we could rely on people to use them properly!
Anyway, there’s a new paper on the arXiv with the title More than half of recent astronomy papers are written with language-model assistance. Here’s the abstract:
As you can see, the claim is that over half of the recent astronomy papers on the astro-ph section of arXiv use Large Language Model (LLM) assistance but that only a tiny fraction of that number declare it. (In my experience those that declare use of LLMs also understate the extent if their use.)
I think this paper is well worth reading. It is based on the excess frequency of certain words and phrases. The authors explain:
Counting excess vocabulary is straightforward. Converting a count into a statement of the form “% of papers used a language model” requires the frequency these words would have had if language models had never been released, and that frequency stopped being observable in November 2022. Statistical precision is not the obstacle, since with hundreds of thousands of papers the observed frequencies are known almost exactly. That frequency can only be supplied by a model, so every estimate in this literature rests on the model chosen for it.
They go on to analyse various models to arrive at their conclusions. I’ll leave it to the reader to go into the details.
One issue I have is that the analysis seems to assume that all changes after the introduction of LLMs in late 2022 are attributable to LLMs. But language changes anyway, and was changing long before AI came on the scene. I would like to see, as a control, a comparison between, say 2006-2010 and 2011-2015 so see if similar changes happened. One problem is that the total number of papers on arXiv is growing monotonically so there are many more papers in 2025 than there were in 2006.
P.S. Ironically, the analysis behind and the writing of this paper were both “assisted” by Claude….
P.P.S. Here’s a suggestion: if you use an LLM to help you write the paper, then you should name it as a co-author.
Today is 11th September 2026 which means it is exactly 25 years since the terrorist attacks on the World Trade Centre and the Pentagon which led to the loss of almost three thousand civilian lives (and many more in the longer term). At the risk of contributing to the deluge of (mainly mawkish) reminiscences about the happenings on this day all that time ago, let me just give a brief account of my recollection. The events of 9/11 are, I suspect, etched on many a memory in much the same way as people remember what they were doing when President Kennedy was assassinated.
For what it’s worth, I was actually at a conference on that day. It was called A New Era in Cosmology, and was hosted in the fine city of Durham; in fact one of the organizers was a certain Tom Shanks, an occasional commenter on this blog. Above you will see part of the conference poster which I took from a recent Facebook post by him where I also found the text below. I was also reminded that 9/11 was the first day of that meeting and that I gave a talk on the first morning, the last before lunch. Such was the effect of the events that unfolded that day that I had completely forgotten about that.
What I do remember is sitting near the back of the lecture theatre after we returned from lunch, listening to one of the afternoon talks – I can’t remember who it was by – when a dear friend of mine, Manuela, came into the auditorium and walked down the aisle, stopped by me. She tugged my arm, mumbled something about the “Twin Towers” and then ran back up the stairs and out of the lecture theatre. Thinking it was something to do with Wembley Stadium, I followed her out and she explained what had happened. We found a TV set, around which a crowd had already formed. The coverage was, not surprisingly, shambolic and it was not until late afternoon that the scale of what had happened became clearer.
There were rumours of more planes likely to be involved in attacks and discussions about whether the military might have to shoot down civilian aircraft. Fortunately that wasn’t the case. I had a friend visiting New York at the time and was unable to contact her by mobile, so was worried, but I don’t think anyone was able to contact anyone in New York by mobile phone in those hours and it turns out she was fine.
Meanwhile the other participants were informed about the events on the other side of the Atlantic. It was an international conference with many US-based attendees who were understandably worried. The preface to the conference proceedings reveals that discussions were held about whether to cancel the meeting:
I think it was the correct decision to proceed with the conference, including the conference dinner and all that. As it happened all passengers flights were grounded for several days anyway, so nobody could get home who didn’t live in the UK.
The rest of the conference was pretty much business as usual as far as possible, although as the text above explains we did stand in silence in memory of the victims on the Tuesday morning. When the meeting ended on the Friday quite a few people had to stay on in Durham or elsewhere before being able to fly home. It was this event that led to the heightened security measures at airports that we have been living with since.
The loss of human life, though awful, turned out to be much less than had been feared and was subsequently dwarfed by the hundreds of thousands killed in the “War on Terror” set in motion by the events of that day and which seems will never end.
Anyway, my point is not the politics but to invite a bit of audience participation. Would anyone else like to contribute their memories from that fateful day? If so, the comment box awaits your entry…
The above picture shows fascist thug and career criminal Daniel Thomas (a.k.a. Danny Tommo) leading a “protest” of uniformed knuckleheads (those on the right of the picture, in short trousers) outside the Daily Mail offices in London.
Fans of P.G. Wodehouse will recall Roderick Spode, the 7th Earl of Sidcup, who leads a fascist group called the “Saviours of Britain” also known as the Black Shorts. He is of course a parody of Oswald Mosley and his group a parody of Mosley’s Black Shirts (aka the British Union of Fascists).
The trouble with you, Spode, is that just because you have succeeded in inducing a handful of half-wits to disfigure the London scene by going about in black shorts, you think you’re someone. You hear them shouting “Heil, Spode!” and you imagine it is the Voice of the People.
How prescient was that?
Incidentally, fans of historical trivia might be interested to know that the grandson of Oswald Mosley (founder of the British Union of Fascists) and Diane Mitford (a friend of Adolf Hitler, who married Oswald Mosley at the home of Joseph Goebbels) is Louis Mosley, CEO of Palantir UK.
Coincidentally, Nigel Farage went to the same school as P.G. Wodehouse, Dulwich College.
When I moved to Ireland, almost nine years ago, one of the words I discovered had a usage with which I was unfamiliar was grind. My first encounter with this was after a lecture on vector calculus when a student asked if I knew of anyone who could offer him grinds. I didn’t know what he meant but was sure it wasn’t the meaning that sprang first into my mind so I just said no, I had just arrived in Ireland so didn’t know of anyone. I resisted the temptation to suggest he try finding an appropriate person via Grindr.
I only found out later that grinds are a form of private tuition and they are quite a big industry in Ireland, particularly at secondary school level. School students whose parents can afford it often take grinds in particular subjects to improve their performance on the Leaving Certificate. It seems to be less common for third level students to pay for grinds, but it does happen. More frequently, university students actually offer grinds to local schoolkids as a kind of part-time employment to help them through college.
The word grind can also refer to a private tutor, i.e. you can have a maths grind. It can also be used as a verb, in which sense it means `to instil or teach by persistent repetition’.
This sense of the word grind may be in use in the United Kingdom but I have never come across it before, and it seems to me to be specific to Ireland at least in current usage. A colleague sent me a link to an article about Carew Arthur Meredith, who worked at Trinity College Dublin from 1943 to 1964 but who was previously at Cambridge University and lived there until 1939:
After graduating, Meredith married Sybil Clark and settled down to what was to be for many years his occupation: that of university coach or “grinder.”
This establishes a possible conduit for the transfer of the word “grinder” from England to Ireland and it inspired me to look at the trusty online Oxford English dictionary which includes examples of usage. In fact the OED gives as examples of “grind” as a transitive or intransitive verbs and as a noun as well as the verbal noun “grinding” and the deverbal noun “grinder”. Here are some pertinent quotes. The first below, incidentally, is from a book of American college slang, demonstrating that the word had crossed the Atlantic by 1851.
Here are the most relevant examples, some of them hilariously susceptible to a double entendre.
n. Steady hard work; labour of a monotonous kind, esp. close and hard study; an instance of this, a dull and laborious task.
1851 Grind, an exaction; an oppressive action. Students speak of a very long lesson which they are required to learn, or of anything which is very unpleasant or difficult to perform as a grind. B. H. Hall, Collection of College Words
1857 A medical student would have told him, that a ‘Grind’ meant the reading up for an examination under the tuition of one who was familiarly termed ‘a Grinder’—a process which Mr. Verdant Green’s friends would phrase as ‘Coaching’ under ‘a Coach’. ‘C. Bede’, Mr. Verdant Green Married xi. 93
vi. To work hard at a subject of study under the direction of a tutor or ‘grinder’.
1835 I am obliged to ‘grind’..that is, undergo a private examination with an authorized teacher or tutor. E. Forbes in G. Wilson & A. Geikie, Memoir of Edward Forbes (1861) vi. 176
1870 After grinding with private-tutor Mylius the requisite time, Lessing entered the school of Camenz. J. R. Lowell, Among my Books (1873) 1st Series 308
vt. To teach (a subject) in a steady laborious manner; also, to prepare (a pupil) in a subject.
1815 implied in: Perhaps when Tom leaves Oxford..we may contrive some gainful grinding [i.e. tutorial] scheme between us. [at grinding n.] J. Keble, Letter to Coleridge in Mem. (1869) iv. 63
1848 A pack of humbugs, and quacks, that weren’t fit to get their living but by grinding Latin and Greek. W. M. Thackeray, Vanity Fair: A Novel Without a Hero lvi. 502
1859 [Dr. Bennett] undertook to grind him in anatomy and physiology. G. Wilson & A. Geikie, Memoir of Edward Forbes vi. 180
In Hard Times by Charles Dickens there is a character by the name of Mr Thomas Gradgrind, a grimly utilitarain school superintendent who insisted on teaching only facts. Hard Times was published in 1854 which is after some of the quotations above so Dickens did not originate the use of “grind” in teaching. He may have amplified it, of course.
This demonstrates that these terms were established in 19th Century England, but does not explain how their usage died out there but still flourishes in Ireland. Can anyone shed light on this? First recorded usages of grind, etc in Irish literature would be most helpful!
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In the Dark 