Archive for the The Universe and Stuff Category

Fine-tuning in Cosmology

Posted in The Universe and Stuff with tags , , , , , on March 25, 2019 by telescoper

I forgot to post a link to a paper by Fred Adams that appeared on the arXiv last month on the topic of the fine-tuning of the Universe which I had bookmarked for a blog a while ago.

My heart always sinks when the arXiv informs me that the abstract of a paper is `abridged’ so here’s the full version from the PDF you can download for yourself here. Please be aware, though, that it’s a lengthy paper running to over two hundred pages:

My own view on this topic is that it is indeed remarkable that the Universe is finely-tuned to exactly the extent required to allow authors to write such long papers about the fine-tuning of the Universe…

 

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Promoting the Open Journal of Astrophysics

Posted in Open Access, The Universe and Stuff with tags , , , on March 24, 2019 by telescoper

The talk I gave at the meeting I attended last week to celebrate the retirement 60th Birthday of Alan Heavens was about the Open Journal of Astrophysics project. Here are the slides:

I decided a while ago that whenever I get the opportunity at conferences or other meetings I will talk about the Open Journal of Astrophysics (OJA for short) , mainly to encourage more submissions but also to raise OJA’s profile so people aren’t tempted to dismiss review invitations as spam from predatory journals.  At the moment, refereeing is the rate-limiting step in the publication process, at least part of the reason being that people don’t really know what we’re about and perhaps assume that it’s not a bona fide operation.

The talk I gave on Friday generated a fair amount of discussion, and was hopefully a small step along the way to establishing OJA as a mainstream journal and perhaps even the default choice for papers on astrophysics. Emma Chapman posted a tweet about my talk (including a picture of me in action) which got quite a lot of attention on Twitter:

 

I’ll just add that you can read more about the extent of the profiteering going on here.

 

Finally, and perhaps most importantly, let me mention I have some money (in a grant courtesy of the Gordon & Betty Moore Foundation) to help promote this project, and I can legitimately spend it on travel to give talks etc.. If anyone would like a talk about this project, please feel free to contact me!

 

The Most Ancient Heavens

Posted in Art, Biographical, Poetry, The Universe and Stuff with tags , , , , , , , , on March 21, 2019 by telescoper

So here I am, in that London, getting ready for the start of a two-day conference at the Royal Astronomical Society on cosmology, large-scale structure, and weak gravitational lensing, to celebrate the work of Professor Alan Heavens, on (or near) the occasion of his 60th birthday. Yes, it is a great name for an astronomer.

I was honoured to be invited to give a talk at this meeting, though my immediate reaction when I was told about was `But he can’t be sixty! He’s only a few years older than me…oh.’ I gather I’m supposed to say something funny after the conference dinner tomorrow night too.

Courtesy of alphabetical order it looks like I’m top of the bill!

Anyway, I’ve known Alan since I was a research student, i.e. over thirty years, and we’re co-authors on 13 papers (all of them since 2011).

Anyway, I’m looking forward to the HeavensFest not only for the scientific programme (which looks excellent) but also for the purpose of celebrating an old friend and colleague.

Just to clear up a couple of artistic points.

First, the title of the meeting, The Most Ancient Heavens, is taken from Ode to Duty by William Wordsworth.

Second, the image on the conference programme shown above is a pastiche of The Creation of Alan Adam which is part of the ceiling of the Sistine Chapel, waswhich painted by Michelangelo di Lodovico Buonarroti Simoni, known to his friends as Michelangelo. Apparently he worked flat out painting this enormous fresco. It was agony but the ecstasy kept him going. I’ve often wondered (a) who did the floor of the Sistine Chapel and (b) how could Michelangelo create such great art when it was so clearly extremely cold? Anyway, I think that is a picture of Alan at high redshift on the far right, next to the man with beard who at least had the good sense to wear a nightie to spare his embarrassment.

Anyway, that’s all for now. I must be going. Time for a stroll down to Piccadilly.

Update: you can find a bunch of pictures of this conference here.

New Publication at the Open Journal of Astrophysics!

Posted in Open Access, The Universe and Stuff with tags , , , , , , , , , on March 20, 2019 by telescoper

It’s nice to be able to announce that the Open Journal of Astrophysics has just published another paper. Here it is!

It’s by Darsh Kodwani, David Alonso and Pedro Ferreira from a combination of Oxford University and Cardiff University.

You can find the accepted version on the arXiv here. This version was accepted after modifications requested by the referee and editor.

This is another one for the `Cosmology and Nongalactic Astrophysics’ folder. We would be happy to get more submissions from other areas of astrophysics. Hint! Hint!

P.S. A few people have asked why the Open Journal of Astrophysics is not listed in the Directory of Open Access Journals. The answer to that is simple: to qualify for listing a journal must publish a minimum of five papers in a year. Since OJA underwent a failure long hiatus after publishing its first batch of papers we don’t yet qualify. However, so far in 2019 we have published four papers and have several others in the pipeline. We will reach the qualifying level soon and when we do I will put in the application!

New Publication at the Open Journal of Astrophysics!

Posted in Open Access, The Universe and Stuff with tags , , , , , on March 13, 2019 by telescoper

It’s nice to be able to announce that the Open Journal of Astrophysics has just published another paper. Here it is!

It’s by Pauline Barmby of the University of Western Ontario. You can find the accepted version on the arXiv here.

I think this paper is a good demonstration of the broad remit of the Open Journal of Astrophysics: our only rule is that if it’s suitable for the astro-ph section of the arXiv then we will consider if for publication. Rather than being a hardcore research paper, this is comprehensive and pedagogical review of observational techniques, instrumentation and data analysis in astronomy for use by researchers and educators in other disciplines, which we feel is a very useful addition to the literature

My thanks to the Editor and referees for dealing with this one so efficiently! We even have a Twitter testimonial from the author:

We have more publications in the pipeline but would be more than happy to receive more…!
I hope soon to get to the point where we have so many papers I can’t write a blog post about every one!

The Gaia Sausage

Posted in The Universe and Stuff with tags , , , , , on March 10, 2019 by telescoper

I had to undertake a top secret mission on Friday, which turned out to be much less exciting than I’d hoped, but at least it gave me an excuse to catch some of the Royal Astronomical Society Open Meeting followed by dinner at the RAS Club. I actually sat next to the Club Guest Michael Duff, the eminent theoretical physicist Michael Duff who gave a nice after-dinner speech.

An artist’s impression of the Gaia Sausage. The Gaia fork has not yet been proved to exist.

The last talk at the RAS Meeting was by Neil Wyn Evans of Cambridge University in the Midlands on the subject of the `Gaia Sausage‘ (which, as you can see, has its own Wikipedia page). The Gaia Sausage is so named because it is consists of a marked anisotropy of the velocity distribution of stars in Milk Way, which is elongated in the radial direction (like a sausage) indicating that many stars are on near-radial (i.e. low angular momentum orbits). This feature has been revealed by studying the second data release from Gaia.

The work Wyn described in his talk is covered by a nice press release from Cambridge University which links to no fewer than five articles on it and related topics, which can all be found on the arXiv here, here, here, here and here.

The most plausible explanation of the Gaia Sausage is that it is a consequence of a major collision between the Milky Way with a smaller galaxy containing about 109 stars about 8-10 billion years ago, as illustrated in this simulation.

I vote that this explanation of the velocity structure of the Milky Way should henceforth be called the Big Banger Theory.

Geddit?

I’ll get my coat.

R. I. P. Wolfgang Rindler (1924-2019)

Posted in Books, Talks and Reviews, Education, The Universe and Stuff with tags , , , , on March 5, 2019 by telescoper

A recent comment on this blog drew my attention to the sad news of the death, at the age of 94, of Wolfgang Rindler. He passed away almost a month ago, in fact, but I have only just heard. My condolences to his family, friends and colleagues.

Wolfgang Rindler was a physicist who specialized in relativity theory and especially its implications for cosmology. Among other things he is attributed with the first use of the phrase `Event Horizon‘ as well as elucidating the nature of horizons in general relativity, both in the context of black holes and in cosmology. I never met him personally but to me, and I think to many other people, Wolfgang Rindler will be familiar through his textbooks on relativity theory. I have two in my collection:

I bought the one on the right on recommendation when I was an undergraduate over thirty years ago and the other (shorter) one I acquired second-hand some years later. Both are still very widely used in undergraduate courses.
I found the first one then (as I do now) rather idiosyncratic in approach and notation but full of deep insights and extremely effective from a pedagogical point of view. I still recommend it to students, to balance more conventional modern texts which tend to be far more conventional. It’s no easy thing to write textbooks and Wolfgang Rindler deserves high praise for having devoted so much of his time, and considerable talent, into writing ones whose impact has been so widespread and lasted so long.

Rest in peace, Wolfgang Rindler (18th May 1924 – 8th February 2019).