Archive for April, 2021

International Jazz Day – A Tribute to Humph

Posted in Biographical, Jazz with tags , , on April 30, 2021 by telescoper

Today is International Jazz Day which gives me an excuse to post this documentary about the late great Humphrey Lyttelton the anniversary of whose death was last weekend; he passed away on 25th April 2008.

I particularly like this programme because, as well as talking about his own career as a musician and bandleader and as brilliant chairman of the panel show I’m Sorry I Haven’t A Clue, it mentions his radio show The Best of Jazz which I listened to avidly every Monday night and from which I learned a huge amount about the music that I love so much. I taped many of these broadcasts actually, but have long since lost the cassettes. Although his own music was in the mainstream he always played a wide selection of Jazz tracks both ancient and modern on his programme and introduced me to many artists I would otherwise never have heard of.

Vaccination Machinations

Posted in Biographical, Covid-19 on April 30, 2021 by telescoper

As Ireland’s Covid-19 vaccination programme stumbles along, well behind schedule, the Irish Government keeps saying – despite all the evidence – that it will meet its target of 82% of the adult population have received a first dose by the end of June. Actually they say that “will either have received or been offered a dose” by then. This may end up with people registering for their shot and being counted if they are given a date to receive it some time later in the year.

As of Wednesday 28th April, 1,067,378 people have received their first dose in Ireland. That will have to increase to to over 3 million to reach the 82% target by the end of June. There is also the fact that only 419,655 have had their second dose so not all the shots delivered in the next two months will be first doses. Looking at the current rate of vaccination, which is around 35,000 per day – it does not seem at all likely to me that it will be possible to hit the target. The Government is claiming 450,000 doses per week in June, which seems not just optimistic but delusional. I hope I’m proved wrong.

Recently the HSE recommended that two of the available vaccines – AstraZeneca and Johnson & Johnson – can only be given to the over-50s, which is the next cohort due to be allowed to register for vaccination (starting next week) and to which I happen to belong. If the Government is to reach its target it will have to use almost all the shots it receives in the next two months, including AZ and J&J. The problem this poses is: (1) the over 50s are next in line, according to the age-based priority system being implemented; and (2) most of the 600,000 J&J doses coming to Ireland won’t arrive until late June.  The number of people currently unvaccinated in the 50-59 age group is about 550,000. The obvious suggestion would therefore to be to make the over-50s wait for the J&J to arrive.

(Of course the over-50s also qualify for the AstraZeneca vaccine, but I won’t discuss that because the supply of that has been so unreliable that it would seem to me to be unwise to count on it for anything. There’s a strong case for just forgetting about AZ and giving the surplus doses to countries that need them more, e.g. India. I also wish the EU well in its legal case against AstraZeneca for multiple and egregious breaches of contract.)

Anyway, unless the advice on use of J&J is changed, the only way to use most of the J&J doses is on the fifty-somethings whose will have to be delayed in order to wait for the doses to arrive. If the decision is made to do this then I won’t be vaccinated until the end of June or later, even if the promised deliveries arrive on schedule. If J&J are as unreliable as AstraZeneca then I may not be vaccinated until much later. The upshot of this shot is that it is a single-shot, so recipients would count as fully vaccinated immediately.

This would also mean  Pfizer/BioNTech and Moderna doses sitting around unused, so there is a case for moving on to younger cohorts to use up these doses until the J&J doses arrive for us oldies. I expect to be able to register for my vaccine next week but it’s anyone’s guess when I’ll actually be able to get my jab. I have even toyed with the idea of going back to Cardiff to get my vaccination there…

I’m pretty much resigned at this stage to having to wait at least another two months to receive my jab, and for that to probably be the J&J vaccine, but the vaccination programme has changed umpteen times during the course of April and it could change again in May. We’ll see. We live in interesting times.

 

 

Cosmology from Home

Posted in The Universe and Stuff on April 29, 2021 by telescoper

Just a quick post to pass on an announcement about the forthcoming Cosmology from Home 2021 conference.

Cosmology from Home is an online cosmology conference with a novel format aimed at bringing the real-world workshop experience into the virtual domain. The format includes the use of pre-recorded talks, and a combination of asynchronous and scheduled live discussions. A freely-navigated virtual office space also facilitates ongoing, organic discussions. The conference will bring together cosmologists from around the world to discuss the current state of cosmology at the interface of theory and observations. For more details see here.

Registration for this event is now open here.

Please note that there will be a limited number of participants so book early!

 

The Definitive Guide to Bird Identification

Posted in Biographical on April 28, 2021 by telescoper
The Definitive Guide to Bird Identification

What with it being the penultimate week of teaching term, today has been full on so I haven’t time for a lengthy post. On very busy days like this I find it quite relaxing watching the birds in my little garden even just for a few minutes in between other things. Over the past few months I think I’ve become quite adept at identifying the various avian visitors so thought I’d share that expert knowledge free of charge with my vast readership via the above graphic.

Name Change Policy at the Open Journal of Astrophysics

Posted in LGBT, Open Access with tags , on April 27, 2021 by telescoper

This lunchtime I took a bit of time out to complete a task that has been on my to-do list for some time. It has been announced in a blog post at the Open Journal of Astrophysics.

The recent announcement by arXiv of a name change policy has enabled the Open Journal of Astrophysics to introduce a policy of its own concerning author name changes. The aim of such a policy is to reduce barriers to changing public records and online identity, thereby fostering diversity and promoting inclusivity. The changes announced follow recommendations by the Committee On Publication Ethics (COPE).

Since the Open Journal of Astrophysics is an arXiv overlay journal which is totally dependent on the arXiv platform we had to wait until arXiv announced its policy before following it with one of our own, which were recently able to do.

The arXiv now allows the following options:

  1. In full text works: the author name can be changed in the PDF and/or LaTeX source where it appears in the author list, acknowledgments, and email address.
  2. In metadata: the name and email address can be changed in the author list metadata and in the submission history metadata for all existing versions.
  3. In user accounts: the name, username, and email address can all be changed.

The arXiv policy notes, however, that

We are not currently able to support name changes in references and citations of works. Also, arXiv cannot make changes to other services, including third party search and discovery tools that may display author lists for papers on arXiv.

Since the Open Journal of Astrophysics deposits author metadata for all our papers with the Crossref system we can plug this gap by undertaking to redeposit all necessary information to reflect author name changes. Since author metadata is attached to the DOI we issue, this will ensure that citations and references tracked through this system are updated when an author changes their name.

If any author of a paper published in the Open Journal of Astrophysics wishes to make use of this policy the best procedure is to first contact the arXiv under their policy. Once any changes have been made to the arXiv submission the author should contact us with a request. We will then make any necessary changes to the overlay on the Open Journal of Astrophysics site and redeposit amended metadata to Crossref free of charge. We also undertake to ensure entries are updated at the NASA/ADS system.

Following the guidance from COPE the Open Journal of Astrophysics will neither seek permission from nor inform co-authors of any such change.

A list of other journals/publishers and their name change policies can be found here.

The State of the Universe Talk

Posted in Biographical, Books, Talks and Reviews, Talks and Reviews, The Universe and Stuff on April 26, 2021 by telescoper

When I saw the calibre of the other speakers in the Chalonge – De Vega Series organized by Norma Sanchez- including a number of Nobel Laureates – it was with some trepidation that I accepted the invitation to give a Colloquium, but there we are. I’m on the list. If you want to attend the Colloquium (via Zoom) you can register for it here. This series was originally named after Daniel Chalonge but was renamed to honour Hector de Vega, who sadly passed away in 2015.

I used to get invited quite often to the famous Norma Sanchez Schools and Conferences in Paris and Sicily (both Erice and Palermo) but then, about a year ago. I was suddenly stopped receiving invitations. I gather that a number of other colleagues have also been abruptly “cancelled” over the years. Anyway it seems I’m back on the list, at least virtually, possibly owing to some form of administrative error.

I remember one year in Erice at the end of a talk I gave (in the OHP/Transparency era) Norma Sanchez, who was meant to be chairing the questions and discussion started writing on my transparencies, crossing out the word “theory” and replacing it with “model”. That event made quite an impression on the audience who thought it was hilarious and people who were there often remind me of it. Coincidentally, I thought of that event when I wrote Saturday’s post. Since the forthcoming colloquium is via Zoom I think I’ll be safe from any such intervention this time.

A First in Azed

Posted in Biographical, Crosswords with tags , , , , on April 25, 2021 by telescoper

I was roused from my Sunday-morning lie-in by the news that I had actually won First Prize in the latest Azed Competition. The best I’ve done previously was third place, and that was almost a decade ago!

As I’ve mentioned before, the monthly Azed Competition puzzle involves not only solving the Azed crossword but also supplying a cryptic clue for a word or phrase given only as a definition in the crossword. This competition is tough, partly because Azed is a stickler for syntactical soundness in submitted clues, and partly because many of the competitors are professional crossword setters.

I’ve struggled this year to find the time and the energy to make a decent attempt at the Azed competition, but the latest competition puzzle was published on Easter Sunday so I had Easter Monday to think about it. Solving the actual puzzle wasn’t too hard this time, which gave me plenty of time to work on the harder bit of composing a clue.

The target word was FILATORY (a machine for spinning thread). For some reason the first thing that popped into my mind was Greek Mythology, specifically the Moirai (Fates) who between them weave the tapestry of life, but one of whom, Clotho, spins the thread. I noticed that one can find the letters of TRIO in FILATORY leaving FAY+L. I looked up FAY in the One True Chambers Dictionary where I found that in its meaning as “fairy” is is derived from the Latin Fata. Even better. I just need to find a way of putting an L into the mix but as a standard abbreviation for “line” that wasn’t too hard.

My clue was

Fay trio with line in weaving? One spins thread.

The second part is the definition (a filatory spins thread) whereas the first part is the word play, FAY TRIO with L forms the basis of an anagram, with “weaving” as the anagram indicator (“anagrind”) instructing the solver to form an anagram.

I think the mythological connection between the two parts of the clue lays a false trail that disguises the definition a bit so I was quite pleased with this effort, thinking it might just get a VHC. I was very surprised to find it winning outright and am absolutely delighted!

I’ve expunged the first line of my address from the scan for obvious reasons, though it is there in the newspaper. I presume it is there because the winner of the Azed Competition not only gets a prize in the form of book tokens but is also sent the Azed Instant Victor Verborum Cup to hold for a month before passing it on to the winner of the next competition, when the result of that is announced, in this case about a month from now. The next Competition puzzle is in next week’s Observer, published on May 2nd. The following day is a Bank Holiday in Ireland so I’ll be able to have a good go at that too.

Presumably the trophy will arrive in the post at some point. With the current state of the mail service between Ireland and the UK I only hope it arrives before I have to send it on to the next winner!

Backwards and Forwards in Science

Posted in Biographical, Maynooth, The Universe and Stuff on April 24, 2021 by telescoper

I spent a few hours today involved with our Open Day at Maynooth University, including – as I mentioned here – giving a presentation about Theoretical Physics to complement one about Experimental Physics followed by a couple of hours of Q&A. It was a bit of a shame to be cooped up inside on such a lovely Spring day but we had a lot of interesting questions and it was all quite enjoyable.

One of the things that I tried to stress in my talk is that while there theorists and experimentalists (or observers), real science is about the interplay between the two, which I’ve illustrated in the above diagram which I use sometimes when talking about cosmology though it applies to other disciplines.

We have theoretical models – normally including a set of free parameters which we don’t know how to fix a priori. What we can do though is calculate the consequences if we did know the values of these parameters. That forward calculation is represented by the upward arrow, using theory to predict the result of a measurement. The backward calculation (inverse reasoning) involves using the measurements to infer values for the free parameters; that’s represented by the downward arrow. There’s usually a considerable amount of back-and-forth between theory space and measurement space as scientific knowledge develops. If one version of a model doesn’t fit we can adjust its parameters until it does, then we might need new data to test this iteration. It is only when the theoretical slack is sufficiently tight and freedom to adjust parameters is eliminated or severely restricted can we really test a theoretical idea definitively.

In cosmology we have only a handful of free parameters and this process has worked pretty well in providing a model in which these parameters are tightly constrained by a host of observational results. This is the standard model and although there a “tensions”, most prominently concerning the Hubble Constant, the model has survived very well. The same situation holds for the standard model of particle physics, though there is tension concerning the muon magnetic moment that I blogged about here.

I’ve written quite a lot on this blog about the inverse reasoning step – partly because I think there are many people (even professional scientists) who don’t understand this part very well and partly because cosmology provides a good example of a model with elements that can’t be calculated from first principles.

It struck me this morning, however, in answering a question about the muon magnetic moment that we often tend to assume that the forward calculation is somehow trivial. In fact the theoretical calculation of (g-2) is nothing of the sort: it requires lengthy supercomputer computations before the theory can make a prediction and there is some doubt over whether the current values of the theoretically expected value of the muon dipole moment are correct within the model.

The same issue arises in cosmology. It is not at all easy to calculate, for example, detailed properties of galaxy clustering in a given cosmological model. The forward calculation here uses huge N-body experiments. This is why a very considerable part of the effort being expended in preparation for the European Space Agency’s Euclid mission is on the simulation side.

Both particle physics and cosmology – and no doubt other fields – are thus limited by how well we can do the forward calculation and that is not going to change very soon. Nevertheless it is the interplay between theory and measurement that has driven the progress so far, and it will continue to do so even if it is the case that the more progress we make the harder it gets to go further.

Climate Change Research at Maynooth University

Posted in Maynooth, The Universe and Stuff on April 23, 2021 by telescoper

Did you know that Maynooth University is Ireland’s leading institution for climate change research and teaching? Researchers are internationally recognized and they are working in areas such as climate modelling, investigating severe weather events and their mitigation, right through to examining the social and economic impacts of climate change.

Here’s a little video about it.

Theorists and Experimentalists in Physics

Posted in Education, Maynooth, The Universe and Stuff with tags , , , on April 22, 2021 by telescoper

Regular readers of his blog (Sid and Doris Bonkers) 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.

Anyway, this year we’ve been thinking very hard about bringing about closer cooperation between the two Physics Departments at Maynooth. It remains to be seen precisely what form that closer cooperation will take but I think it’s a good idea in principle. In fact in the Open Day at Maynooth coming up on Saturday 24th April there will, for the first time ever, be a joint talk by the Departments of Theoretical Physics and Experimental Physics. I’m looking forward to seeing how that goes!