Archive for May, 2018

Planck wins the Gruber Prize (and the Shaw Prize)

Posted in Science Politics, The Universe and Stuff with tags , , on May 13, 2018 by telescoper

I forgot to mention last week that the 2018 Gruber Prize for Cosmology has been awarded to the Planck team, and its Principal Investigators Nazzareno Mandolesi and Jean-Loup Puget.

For more information about the award and the citation, see here.

This annual prize is worth $500,00; the two PIs will get $125,000 each and the rest divided among the team. I’m not sure whether this means the Planck Science Team (whose membership is listed here or the entire Planck Collaboration (which numbers several hundred people) but regardless of whoever gets the actual dosh, this award provides a good excuse to send congratulations to everyone who worked on this brilliant and highly successful mission!

 

UPDATE: 14th May 2018. Jean-Loup Puget has also been awarded the Shaw Prize for Astronomy.

100 Years of Feynman

Posted in Cute Problems, Education with tags , , , , , , on May 11, 2018 by telescoper

Today marks the centenary of the birth of Noble Prize-winning physicist, science communicator and bongo player Richard Feyman. It’s great to see so many articles about him today, so I was wondering how to do my own quick tribute before I head to London for the Royal Astronomical Society Annual General Meeting this afternoon.

With university exams coming up it seemed a good idea to celebrate Richard Feynman’s legacy by combining todays 100th anniversary with some tips (inspired by Feynman) about how to tackle physics problems, not only in terms of how to solve them but also how to present the answer in an appropriate way.

Richard-Feynman-cornellI began with Richard Feynman’s formula (the geezer in the above picture) for solving physics problems:

  1. Write down the problem.
  2. Think very hard.
  3. Write down the answer.

That may seem either arrogant or facetious, or just a bit of a joke, but that’s really just the middle bit. Feynman’s advice on points 1 and 3 is absolutely spot on and worth repeating many times to an audience of physics students.

I’m a throwback to an older style of school education when the approach to solving unseen mathematical or scientific problems was emphasized much more than it is now. Nowadays much more detailed instructions are given in School examinations than in my day, often to the extent that students  are only required to fill in blanks in a solution that has already been mapped out.

I find that many, particularly first-year, students struggle when confronted with a problem with nothing but a blank sheet of paper to write the solution on. The biggest problem we face in physics education, in my view, is not the lack of mathematical skill or background scientific knowledge needed to perform calculations, but a lack of experience of how to set the problem up in the first place and a consequent uncertainty about, or even fear of, how to start. I call this “blank paper syndrome”.

In this context, Feynman’s advice is the key to the first step of solving a problem. When I give tips to students I usually make the first step a bit more general, however. It’s important to read the question too. The key point is to write down the information given in the question and then try to think how it might be connected to the answer. To start with, define appropriate symbols and draw relevant diagrams. Also write down what you’re expected to prove or calculate and what physics might relate that to the information given.

The middle step is more difficult and often relies on flair or the ability to engage in lateral thinking, which some people do more easily than others, but that does not mean it can’t be nurtured.  The key part is to look at what you wrote down in the first step, and then apply your little grey cells to teasing out – with the aid of your physics knowledge – things that can lead you to the answer, perhaps via some intermediate quantities not given directly in the question. This is the part where some students get stuck and what one often finds is an impenetrable jumble of mathematical symbols  swirling around randomly on the page. The process of problem solving is not always linear. Sometimes it helps to work back a little from the answer you are expected to prove before you can return to the beginning and find a way forward.

Everyone gets stuck sometimes, but you can do yourself a big favour by at least putting some words in amongst the algebra to explain what it is you were attempting to do. That way, even if you get it wrong, you can be given some credit for having an idea of what direction you were thinking of travelling.

The last of Feynman’s steps  is also important. I lost count of the coursework attempts I marked this week in which the student got almost to the end, but didn’t finish with a clear statement of the answer to the question posed and just left a formula dangling.  Perhaps it’s because the students might have forgotten what they started out trying to do, but it seems very curious to me to get so far into a solution without making absolutely sure you score the points.  IHaving done all the hard work, you should learn to savour the finale in which you write “Therefore the answer is…” or “This proves the required result”. Scripts that don’t do this are like detective stories missing the last few pages in which the name of the murderer is finally revealed.

So, putting all these together, here are the three tips I gave to my undergraduate students this morning.

  1. Read the question! Some students give solutions to problems other than that which is posed. Make sure you read the question carefully. A good habit to get into is first to translate everything given in the question into mathematical form and define any variables you need right at the outset. Also drawing a diagram helps a lot in visualizing the situation, especially helping to elucidate any relevant symmetries.
  2. Remember to explain your reasoning when doing a mathematical solution. Sometimes it is very difficult to understand what students are trying to do from the maths alone, which makes it difficult to give partial credit if they are trying to the right thing but just make, e.g., a sign error.
  3.  Finish your solution appropriately by stating the answer clearly (and, where relevant, in correct units). Do not let your solution fizzle out – make sure the marker knows you have reached the end and that you have done what was requested. In other words, finish with a flourish!

There are other tips I might add – such as checking answers by doing the numerical parts at least twice on your calculator and thinking about whether the order-of-magnitude of the answer is physically reasonable – but these are minor compared to the overall strategy.

And another thing is not to be discouraged if you find physics problems difficult. Never give up without a fight. It’s only by trying difficult things that you can improve your ability by learning from your mistakes. It’s not the job of a physics lecturer to make physics seem easy but to encourage you to believe that you can do things that are difficult!

 

The Joy of Fecks

Posted in Television with tags , , , , , on May 10, 2018 by telescoper

One of the things I’ve noticed in the time I’ve spent in the Dublin area recently is that Irish people tend to swear a lot, and I mean a lot. On the other hand, the combination of an Irish accent and the imaginative way in which expletives are used makes this habit colourful rather than offensive.

Something I have discovered only relatively recently concerns the word `feck’ (as used frequently by Father Jack in the comedy documentary series Father Ted). I’ve always assumed that this word was simply an alternative form for the word `fuck’ and as such was an extremely offensive swear word. I have used it frequently in the Irish vernacular phrase “feckin’ eejit” (usually in the context of a British politician) assuming that it had that meaning.

However, I am reliably informed by Irish colleagues and Wikipedia – although I’m not sure whether either of those sources really counts as reliable – that `feck’ isn’t really the same as `fuck’ because it derives from a different root, and although it is an oath it is far less offensive. In fact, `feck’ is a word which is also in use in Scotland meaning force or value, from which we get the word `feckless’ meaning worthless, or something like `a large amount or quantity’.

In modern Irish slang, `feck’ can be used as a `minced oath’ (i.e as a euphemism for `fuck’, as one might say `eff off’ instead of `fuck off’) but it has a variety of other meanings, including `to steal’ or `to throw’. None of these other meanings relate directly to sexual intercourse. In summary, then, it seems that while `feck’ is undoubtedly rather vulgar, it is far less offensive than `the bad F-word’, i.e. `fuck’.

I hope this doesn’t give the impression that my opening statement – that Irish people swear a lot – is false. ‘The bad F-word’ is definitely in widespread use. All I’m saying is that `feck’ (a) isn’t the same word and (b) it’s not as offensive as you might have thought.

Here’s an explanation by the inestimable Mrs Doyle from Father Ted in which she discusses these issues in the context of modern Irish literature.

Now I think I’ll feck off home.

Revisionist (Thermal) History of the Universe

Posted in Biographical, Cardiff, Education, The Universe and Stuff with tags , , on May 10, 2018 by telescoper

Well, today saw my last teaching session on my Cardiff University module Physics of the Early Universe. It was actually an optional revision lecture, during which I went through questions on last year’s examination paper, some matters arising therefrom and some general tips on `examination technique’. The latter included advice that seems obvious – such as `read the question carefully’ and `check your numerical answers’ – but that surprisingly many students seem not to have heard before or, if they have, choose not to follow!

Anyway, I hope the students who came today found it useful and I hope that they (and indeed everyone else taking examinations over the next few weeks) do themselves proper justice and get the results they need for whatever comes next in their plans.

The Physics of the Early Universe paper is a couple of weeks ago so no doubt I’ll get a few more queries to deal with before then.

I thought I’d give an idea of the stuff I’ve been teaching here by including one of the questions from last year’s paper. I thought this was quite an easy one, actually, but the students seemed to find it tricky while they mostly coped well with the other questions, which I thought were harder. One of the challenges of teaching is that it’s often hard to see what other people find difficult! See what you think. You don’t really need to know much cosmology to do this:

Anyway, today was not only the last teaching session for this particular module – it’s also the last teaching session I’ll ever conduct in the UK university system. Best wishes to whoever it is that teaches this module next year when I’m in Ireland.

When youthful faith has fled

Posted in Poetry with tags , , , on May 9, 2018 by telescoper

When youthful faith has fled,
PU Of loving take thy leave;
Be constant to the dead –
PUThe dead cannot deceive.

Sweet modest flowers of spring,
PUHow fleet your balmy day!
And man’s brief year can bring
PUNo secondary May.

No earthly burst again
PUOf gladness out of gloom;
Fond hope and vision vain,
PUUngrateful to the tomb!

But ’tis an old belief,
PUThat on some solemn shore,
Beyond the sphere of grief,
PUDear friends will meet once more.

Beyond the sphere of time,
PUAnd sin, and fate’s control,
Serene in changeless prime
PUOf body and of soul.

That creed I fain would keep,
PUThat hope I’ll not forego;
Eternal be the sleep,
PUUnless to waken so.

by John Gibson Lockhart (1794-1854). The last three verses of this poem were adapted by Hubert Parry as No. 4 `There is an old belief’ in his Songs of Farewell.

 

Celebrating the Sloan Telescope

Posted in The Universe and Stuff with tags , , , , , , , , on May 9, 2018 by telescoper

A little bird tweeted at me this morning that today is the 20th anniversary of first light through the Sloan Telescope (funded by the Alfred P. Sloan Foundation) which has, for the past two decades, been surveying as much of the sky as it can from its location in New Mexico (about 25% altogether): the Sloan Digital Sky Survey is now on its 14th data release.

Here’s a picture of the telescope:

For those of you who want the optical details, the Sloan Telescope is a 2.5-m f/5 modified Ritchey-Chrétien altitude-azimuth telescope located at Apache Point Observatory, in south east New Mexico (Latitude 32° 46′ 49.30″ N, Longitude 105° 49′ 13.50″ W, Elevation 2788m). A 1.08 m secondary mirror and two corrector lenses result in a 3° distortion-free field of view. The telescope is described in detail in a paper by Gunn et al. (2006).

A 2.5m telescope of modest size by the standards of modern astronomical research, but the real assets of the Sloan telescope is a giant mosaic camera, highly efficient instruments and a big investment in the software required to generate and curate the huge data sets it creates. A key feature of SDSS is that its data sets are publicly available and, as such, they have been used in countless studies by a huge fraction of the astronomical community.

The Sloan Digital Sky Survey’s original `legacy’ survey was basically a huge spectroscopic redshift survey, mapping the positions of galaxies and quasars in three dimensions to reveal the `cosmic web’ in unprecedented detail:

As it has been updated and modernised, the Sloan Telescope has been involved in a range of other surveys aimed at uncovering different aspects of the universe around us, including several programmes still ongoing.

Ticket to Ride

Posted in Biographical, Cardiff on May 8, 2018 by telescoper

Although ostensibly based in Cardiff this week I was today required to attend a meeting in London.

This morning I travelled to London Paddington. Inevitably the train was late. The advertised 10 carriage train also turned out to have only 5 carriages and was crammed; there were no seat reservations.

The meeting I attended was quite productive, and I had a nice walk back to Paddington in the warm sunshine.

Now I’m on the return train which also has only five carriages. It seems like Late Western policy to run trains with a short formation in order to maximise the discomfort of passengers. I do not know yet know if we will arrive on time in Cardiff.

My ticket (a one-day ‘off peak’ travelcard) cost £109.10, roughly the cost of two return flights between Cardiff and Dublin.

As a bonus though I got this:

I’ve always wanted to go there, but I’m not sure I want to visit four times. (For those of you not familiar with British geography, ‘Void’ is a place in the Midlands..)

If anyone thinks the pricing of UK train tickets would be reasonable even if the trains ran on time please explain your reasons via the comments box.

My own view, for what it’s worth, is that the travelling public are being fleeced.

Stock Photo

Posted in Uncategorized on May 7, 2018 by telescoper

I’m too busy cooking today to do a proper blog so I’ve resorted to posting this stock photo.

A Day of Sports in Cardiff

Posted in Cardiff, Cricket, Football with tags , , on May 6, 2018 by telescoper

Today I saw my first day of County Cricket this season at Sophia Gardens. It was actually the 3rd day of Glamorgan against Kent, which also turned out to be the last, as Kent won by six wickets.

Defeat for Glamorgan looked pretty inevitable after a horrendous first innings batting collapse from 57-0 to 94 all out. Although they dismissed Kent for 174 and scored 274 in their second innings, the lead of 194 never looked like being enough. On the other hand Yorkshire won their latest match against Essex despite being all out for 50 in their first innings!

As it turned out, in the warm sunshine and good batting conditions, Glamorgan’s bowlers tried hard but didn’t have much luck and never really looked like precipitating the sort of collapse that they needed to win the game.

Today’s play began with a farcical delay caused by a leak in the underground drainage system beneath the square which caused a wet patch. Play was delayed until 12.40 and the players had an early lunch while the sun did its work drying out the square. I’m not sure how this happened but it didn’t affect the game, which was always going to finish today given that there was no chance of the weather intervening. .

A very disappointing result for Glamorgan, but hopefully they can rebound in their next game.

Anyway, just before 2.30pm those of us inside Sophia Gardens (only abiut 250) could hear the sound of fireworks from the Cardiff City Stadium (which is about 20 minutes walk away). Despite only drawing today’s match against Reading, Cardiff City are promoted to the Premiership for next season in second place. They have Birmingham City to thank for that, who beat Fulham 3-1 to secure their Championship survival and prevent Fulham from finishing ahead of Cardiff. Miss Lemon will be pleased.

At the other end of the table, Barnsley, Burton Albion join already relegated Sunderland in League One. The three relegated clubs, once again, are all from the Midlands. It’s strange how often that happens..

Out Thinkers Dublin

Posted in LGBT, Maynooth on May 5, 2018 by telescoper

I’m back in sunny Cardiff and have quite a lot to do today, so I’ll just do a quick post to say that yesterday I left work in Maynooth slightly earlier than usual to take the train onto Dublin for an event called ‘Out Thinkers’ at the Science Gallery in Dublin. I got there in good time before the show, which was held in a nice little theatre inside the Science Gallery, which is about 15 minutes walk from Connolly Station.

Out Thinkers serves to showcase the talent of LGBT+ researchers, providing a platform where people can talk about their scientific work while truly being themselves. This Out Thinkers event featured a range speakers talking about their research and experiences as LGBT+ individuals in academia.

It was a very enjoyable event and it was a nice opportunity to see some familiar (and some unfamiliar) faces in a new setting.

Sadly, because the event overran a but I had to leave before the finish to get a train back to Maynooth so I didn’t get the chance to say goodbye and thanks to the organisers for the splendid show!