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“Optimized” Beer Glass Shapes

Posted in The Universe and Stuff with tags , , , on October 21, 2024 by telescoper

I couldn’t resist sharing a piece of fundamental research I found in an article on the arXiv withthe abstract:

This paper addresses the problem of determining the optimum shape for a beer glass that minimizes the heat transfer while the liquid is consumed, thereby keeping it cold for as long as possible. The proposed solution avoids the use of insulating materials. The glass is modeled as a body of revolution generated by a smooth curve, constructed from a material with negligible thermal resistance, but insulated at the base. The ordinary differential equation describing the problem is derived from the first law of Thermodynamics applied to a control volume encompassing the liquid. This is an inverse optimization problem, aiming to find the shape of the glass (represented by curve S) that minimizes the heat transfer rate. In contrast, the direct problem aims to determine the heat transfer rate for a given geometry. The solution obtained here is analytic, and the resulting function describing the relation between height ans radius of the glass, is in closed form, providing a family of optimal glass shapes that can be manufactured by conventional methods. Special attention is payed to the dimensions and the capacity of the resulting shapes.

arXiv:2410.12043v1

The author’s favourite shape is this:

Of course those of us who are used to proper beer don’t really want it to be cold in the first place, but I hope this doesn’t sound bitter. My main reservation about the conclusion of the paper is that it doesn’t seem to take into account how easy it is to drink from the glass. In that respect, I’m not convinced by the shape above!

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Six New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , on October 19, 2024 by telescoper

It’s Saturday morning again and time to post an update of activity at the Open Journal of Astrophysics. As last week there are six papers to announce, bringing the count in Volume 7 (2024) up to 93 and the total altogether up to 208.

In chronological order, the six 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, published on Monday 14th October 2024, is in the folder marked Cosmology and NonGalactic Astrophysics and is called “Backreaction in Numerical Relativity: Averaging on Newtonian gauge-like hypersurfaces in Einstein Toolkit cosmological simulations“. This paper presents a numerical study of the effect of local inhomogeneities on the dynamical evolution of the Universe, i.e. the so-called “backreaction” problem; the authors are Alexander Oestreicher and Sofie Marie Koksbang of the University of Southern Denmark, Odense, Denmark.

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, published on 15th October 2024, is “Weak-Lensing Shear-Selected Galaxy Clusters from the Hyper Suprime-Cam Subaru Strategic Program: II. Cosmological Constraints from the Cluster Abundance” by I-Non Chiu (National Cheng Kung University, Taiwan) and 11 others based in Taiwan, Japan, India and the USA. This paper, which is also in the folder Cosmology and NonGalactic Astrophysics  presents constraints on cosmological parameters obtained from a sample of galaxy clusters

You can see the overlay here:

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

The third paper is “Image formation near hyperbolic umbilic in strong gravitational lensing” by Ashish Kumar Meena (Ben Gurion University, Israel) and Jasjeet Singh Bagla (IISER Mohali, India). It presents a detailed theoretical discussion of a particular form of strong gravitational lensing and its observational consequences; it is in the folder Astrophysics of Galaxies and was published on October 15th 2024.

The overlay is here:

 

The officially accepted version can be found on arXiv here.

The fourth paper, published on 16th October 2024 and in the folder Astrophysics of Galaxies,  is “Weak Gravitational Lensing around Low Surface Brightness Galaxies in the DES Year 3 Data” by N. Chicoine (University of Chicago, USA) et al. (105 authors; DES Collaboration). It presents a  demonstration of the viability of using weak gravitational lensing to constrain the halo masses of low surface brightness galaxies.

The overlay is here

 

You can find the officially accepted version of this paper here.

The fifth paper in this batch is “Imprints of interaction processes in the globular cluster system of NGC 3640” by Ana I Ennis (Waterloo, Canada) and Juan Pablo Caso & Lilia Patricia Bassino (Instituto de Astrofísica de La Plata, Argentina). This one was also published on 16th October 2024 and is in the folder Astrophysics of Galaxies, Here is the overlay

 

 

You can find the official accepted version on the arXiv here.

Finally for this week we have “On the nature of the C IV-bearing circumgalactic medium at 𝒛∼𝟏” by Suyash Kumar, Hsiao-Wen Chen, Zhijie Qu & Mandy C. Chen (U. Chicago), Fakhri S. Zahedy (U. North Texas), Sean D. Johnson (Carnegie Observatories), Sowgat Muzahid (IUCAA, India) and Sebastiano Cantalupo (U. Milan Bicocca)

The overlay is here

 

You can find the officially-accepted version on arXiv here.

That’s it for now. More next week!

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A Taste of the Euclid Survey

Posted in Euclid, The Universe and Stuff with tags , , , on October 15, 2024 by telescoper

Today (15th October 2024) saw the release of a sneak preview of the main survey of the European Space Agency’s Euclid survey at the International Astronautical Congress in Milan. Here’s the key image.

This image is not at full science resolution of the Euclid survey and is meant primarily as an appetizer. The resolution is11Kx4K,  and is processed by the same pipeline that produced the Euclid Early Release Observations featured here and here. You can find more detail about these images here and here. I have taken this from the latter article:

Euclid has been surveying the sky since 14 February 2024 and data processing is in full swing – the first public release of 53 deg² of science-grade Wide Survey data will take place in March next year. But how much data has Euclid already observed and how can we possibly visualize this? At a rate of 10 deg² per day, the Euclid Wide Survey has already surpassed 1000 deg², that is 5000x the apparent size of the Moon in the sky! Now ESA has put out a first set of images that allow to grasp how much data Euclid is and will be producing.

There’s also this explanatory video:

This is just taster. The main survey will take many years to complete. But it’s a start…

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Six New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , on October 12, 2024 by telescoper

Regular readers of this blog (both of them) will have noticed that I didn’t post an update of activity at the Open Journal of Astrophysics last weekend. Despite having accepted several papers for publication in the preceding week, no final versions had made it onto the arXiv. We can’t published a paper until the authors post the final version, so that meant a bit of a backlog developed. This week included one day with no arXiv update (owing to a US holiday on Tuesday 8th October) and a major glitch on Crossref on Thursday which delayed a couple, but even so we’ve published six papers which is the most we’ve ever managed in a week. This week saw the publication of our 200th article; the total as of today is 202.  The count in Volume 7 (2024) is now up to 87; we have four papers in the queue for publication so we should pass 90 next week if all goes well.

In chronological order, the six 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, published on Monday 7th October 2024 is “z~2 dual AGN host galaxies are disky: stellar kinematics in the ASTRID Simulation” by Ekaterina Dadiani (CMU; Carnegie Mellon U.) Tiziana di Matteo (CMU), Nianyi Chen (CMU), Patrick Lachance (CMU), Yue Shen (U. Illinois at Urbana-Champaign), Yu-Ching Chen (Johns Hopkins U.), Rupert Croft (CMU), Yueying Ni (CfA Harvard) and Simeon Bird (U. California Riverside) – all based in the USA. The paper, which is in the folder marked Astrophysics of Galaxies describes a numerical study of the morphology of AGN host galaxies containing close pairs of black holes.

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, published on 8th October 2024, is “Origin of LAMOST J1010+2358 Revisited” by S.K. Jeena and Projjwal Banerjee of the Indian Institute of Technology Palakkad, Kerala, India. This paper discusses  the possible formation mechanisms for Very Metal Poor (VMP) stars and the implications for the origin of LAMOST J1010+2358 and is in the folder marked Solar and Stellar Astrophysics.

You can see the overlay here:

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

The third paper is very different in both style and content: “Assessing your Observatory’s Impact: Best Practices in Establishing and Maintaining Observatory Bibliographies” by Raffaele D’Abrusco (Harvard CfA and 14 others; the Observatory Bibliographers Collaboration) and is in the folder marked Instrumentation and Methods for Astrophysics. It presents discussion of the methods used by astronomical observatories to construct and analyze bibliographic databases. The overlay is here:

(This one gave me a rare opportunity to use the library of stock images that comes with the Scholastica platform!) The officially accepted version can be found on arXiv here.

The fourth paper, also published on 8th October 2024, and our 200th publication, is in the folder marked Cosmology and NonGalactic Astrophysics, and is called “CombineHarvesterFlow: Joint Probe Analysis Made Easy with Normalizing Flows“. The authors are Peter L. Taylor, Andrei Cuceu, Chun-Hao To, and Erik A. Zaborowski of Ohio State University, USA. The article presents a new method that speeds up the sampling of joint posterior distributions in the context of inference using combinations of data sets. The overlay is here

You can find the officially accepted version of this paper here.

The fifth paper in this batch is “Estimating Exoplanet Mass using Machine Learning on Incomplete Datasets” by Florian Lalande (Okinawa Institute of Science and Technology), Elizabeth Tasker (Institute of Space and Astronautical Science, Kanagawa) and Kenji Doya (Okinawa); all based in Japan. This one was published on 10th October 2024 in the folder marked Earth and Planetary Astrophysics. It compares different methods for inferring exoplanet masses in catalogues with missing data

 

 

You can find the official accepted version on the arXiv here.

Finally for this week we have “Forecasting the accuracy of velocity-field reconstruction” by Chris Blake and Ryan Turner of Swinburne University of Technology, Melbourne, Australia. This was also published on 10th October 2024 and is in the folder marked Cosmology and NonGalactic Astrophysics. The paper describes a numerical study of the reliability and precision of different methods of velocity-density reconstruction. The overlay is here

You can find the officially-accepted version on arXiv here.

That’s it for now. We have published six papers, with a very wide geographical spread of authors, and in five of the six astro-ph categories we cover. I think it’s been a good week!

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Predicting the Future of Publishing from the Past

Posted in Open Access, The Universe and Stuff with tags , , , , on October 11, 2024 by telescoper

I was intrigued by an editorial piece from 20 years ago that was sent to me by Prof. Peter Schneider (who, among many other things, is Chair of the Euclid Consortium Editorial Board) who happens to be one of the authors. The article gives an interesting insight into the processes involved in being an Editor for the journal Astronomy and Astrophysics (A&A) at the time, and is worth reading all the way through, but I was particularly struck by Section 6.2, which makes some predictions about the future.

Here’s an excerpt:

We can even go a step further and ask the provocative question of whether we will need a peer-reviewed journal like A&A in the future. After all, in some communities, astro-ph has taken over the role of communicating new results. Is astro-ph not sufficient? A few aspects of a potentially very long answer to that question are as follows: many authors submit their manuscript to astro-ph, but only after it has been peer-reviewed, which shows that most researchers consider the peer-reviewing essential. People’s achievements are often judged by their refereed papers. Certainly at present, peer-reviewing is seen as a kind of quality stamp on manuscripts, and we are here to witness that papers are improved in the course of the refereeing process.


But what if astro-ph is supplemented by a refereeing process, essentially in the same way as the major journals do today, so that a manuscript gets a “green tick-mark” after successfully passing the reviewing stage and being “frozen”, i.e., cannot be replaced with an updated version anymore. We suspect that this is possible, although it would require a fairly large board of Editors to cope with the numbers of submissions to astro-ph, accompanied by costs that would have to be covered by someone. If this system were to replace the current journals, then one would end up with a single electronic-only astronomy journal and preprint service system. What if a paper is not passing through the refereeing stage? At present, a paper rejected by one journal can still be submitted to a second one, thus getting another chance to be published. We consider this second-chance opportunity a necessary feature for a fair peer-reviewed information flow. Hence, we would need more than one “astro-ph”-like system with different boards of editors, and this brings us back closely to a system of several electronic-only journals.

This is basically the idea behind the Open Journal of Astrophysics, which I didn’t really start thinking about until about 2010. In fact, when we were talking about setting up OJAp – about a decade after this paper was written – we did discuss the possibility of just having a “green tick-mark” on the arXiv entry. We rejected this idea in favour of the overlay concept primarily because of security concerns about who writes the tick mark into the arXiv field. I do agree with the point about having multiple platforms for such publications, however, and I have frequently argued that there should be alternatives to OJAp.

Here is another extract, from the very end of the paper:

We have taken here the role of devil’s advocate to demonstrate that issues in going electronic-only are far from being as simple and clear-cut as some open-access gurus would like us to believe. Obviously, electronic publishing is a timely and controversial issue that we will continue to consider in the coming years. The future of publication will be decided less by Boards of Directors and Editors, or by publishers, than by the community at large. With the availability of electronic-only journals, authors make their own decision on where to submit a manuscript. At present, this vote is clearly in favor of traditional journals, but as that may change we will remain open and ready to adapt.

I would hesitate to call myself a “guru” but I do think that the issues are clearer now than perhaps they were in 2004. Twenty years on, the balance is still in favour of traditional journals at least in terms of numbers of papers being published. Judging by the activity at OJAp, it may be that things may be changing…

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Space Week 2024: The Universe according to Euclid

Posted in Biographical, Books, Talks and Reviews, Euclid, The Universe and Stuff with tags , , , , , on October 10, 2024 by telescoper

I had a very busy day yesterday culminating in the Space Week event I blogged about a few weeks ago. There was a good attendance – lots of young kids as well as adults – and the lecture room was very full. We could probably have filled a much bigger room, actually, but had been moved to a smaller venue and had to close registrations very early to avoid having too many people. I’d guess we had about 350. My talk was the last one, and didn’t finish until 8.30 by which time I was definitely ready for a pint.

You can find the slides I used for my presentation, The Universe according to Euclid, here.

There was an official photographer there who took quite a few pictures but I haven’t seen any of them yet. I’ll post a selection if and when I get them.

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The 200th Publication at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , on October 8, 2024 by telescoper

It was on September 11th last year that we published the 100th paper at the Open Journal of Astrophysics. Today, on 8th October 2024, just over a year later we have reached the 200 mark with this paper:

In fact this looks like being a record-breaking week for OJAp as we have published four papers already and its only Tuesday. To be fair, most of these were accepted last week but were slow appearing on the arXiv – I think partly due to glitches on arXiv – but still it’s nice to be this active. I’ll do a regular post at the weekend with details of how many we published in total by then. I’m very confident that we will reach 100 for the calendar year.

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Nobel Prize for Physics Speculation

Posted in Biographical, Science Politics, The Universe and Stuff with tags , on October 6, 2024 by telescoper

Just  to mention that that Tuesday (October 8th 2024) will see the announcement of this year’s Nobel Prize for Physics. I must remember to make sure my mobile phone is fully charged so I can be easily reached.

The announcement of the Nobel Prize for Physics is preceded tomorrow (Monday) by the announcement of the Prize for Applications of Physics to Physiology or Medicine, and on Wednesday by the Prize for Applications of Physics to Chemistry. You can find links to all the announcements here.

I do, of course, already have a Nobel Prize Medal of my own already, dating from 2006, when I was lucky enough to attend the prize-giving ceremony and banquet.

I was, however, a guest of the Nobel Foundation rather than a prizewinner, so my medal is made of chocolate rather than gold. I think after 17 years the chocolate is now inedible, but it serves as a souvenir of a very nice weekend in Stockholm!

Regular readers of this blog may recall that I called it correctly in 2022 when Alain Aspect, John F. Clauser and Anton Zeilinger won the Nobel Prize for Physics that year. I had, however, predicted them every year for many years until they won, and they won’t win it again. I really have no idea who will win it this year, but I’ll suggest that there’s still an outside chance for Michael Berry and Yakir Aharonov for their work on the geometric phase, although if they were going to win they probably would have done so by now.

Feel free to make your predictions through the comments box below!

To find out you’ll have to wait for the announcement, around about 10.45 (UK/Irish time) on Tuesday morning. I’ll update this post when the wavefunction has collapsed.

P.S. My own claim for the 2023 Physics Nobel Prize is based on the discovery of the Coles Law.

P.P.S. I’ve just realized this was my 7000th blog post.

UPDATE: The 2024 Nobel Prize for Physics goes to was awarded to John J. Hopfield and Geoffrey E. Hinton “for foundational discoveries and inventions that enable machine learning with artificial neural networks”. Odd. Not really physics, IMHO.

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Maynooth Space Week Update!

Posted in Maynooth, The Universe and Stuff with tags , on October 1, 2024 by telescoper
Euclid View of the Perseus Cluster

A couple of week ago I posted about the event we are putting on at Maynooth University to mark Space Week in Ireland, which is is from October 4th – 10th this year. The event at Maynooth is on Wednesday October 9th, i.e. a week tomorrow. I’ll be doing a talk, the description of which reads:

Two of the greatest mysteries in modern science concern the nature of the dark matter and dark energy we think dominate the Universe. In this talk I will explain how the European Space Agency’s Euclid mission, launched last year, is designed to shed light on the “dark side” of the cosmos, present some of the early results, and show how you can get involved in analyzing Euclid data.

Anyway, I did think today would provide a good excuse to boost the bookings, but I’m afraid the venue is already full so I needn’t have bothered.

Register on Eventbrite

If you didn’t manage to book you can at least read the programme here to see what you’re going to miss!

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The Shortest Physics Paper Ever?

Posted in The Universe and Stuff with tags , , on October 1, 2024 by telescoper

I thought I’d share this for the benefit of those who haven’t seen it already:

Published in the Physical Review in 1951 this paper is just 27 words long, contains one number (+ error bounds), one equation, and one reference. Is this the shortest physics paper ever?

P.S. Current measurements of the electron and proton masses give a ratio inconsistent with the number derived from the measurements in [1].

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