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Goodbye Virgin Media, and good riddance…

Posted in Biographical with tags , , , , on January 5, 2013 by telescoper

Virgin-Media-logo

With my move to Brighton imminent, I decided before Christmas to sort out a few things that I’ve been putting off for a while. One of them was to cancel the contract with Virgin Media at my house in Cardiff. Having made the decision to ditch them, I then received a letter from said company announcing that their “broadband” service would go up in price in February 2013 by almost 10%. That’s on top of a similar rise earlier in 2012. A price hike of 20% in a year is nothing short of a rip-off. I wouldn’t mind if the service was decent, but the broadband is particularly poor; I’m supposed to have a 20MB service but I rarely get even a tenth of that. I assume Virgin Media simply doesn’t have enough bandwith to deliver what it promises. And that’s not counting when the connection falls over completely, which is far from uncommon…

In 2012 Virgin Media announced that I was getting a “free” upgrade to 20MB – previously I had the cheapo 10MB service – which sounded great. Then, just over a month later, the cost of my broadband package went up by about 10%. That’s a clear misrepresentation, and I should have cancelled my account right away then. But for some reason I didn’t.

I also get a cable TV package from Virgin Media (which I very rarely watch). Cancelling that will probably mean I spend just a bit more time reading or listening to music, which is a good thing. The woeful state of TV generally, and the dire offerings available at Christmas in particular, make me confident that I can live quite happily without it. And I’ll save the license fee too. I also have a telephone land line which I hardly use either. So scrap it all, I thought.

Anyway, I picked up the phone and called Virgin Media on 8th December with the intention of cancelling my service. A very frustrating experience with automated responses followed. “You now have five options”, you know the sort of thing. After several sets of five options (none of which were to cancel my account), I got through to a vaguely humanoid life-form. Even that wasn’t the end of the story as instead of just following my request she asked dozens of irrelevant questions and tried to persuade me not to quit. In the end I got fed up and said “I’m not going to change my mind, please just cut the crap and cancel the account”. Finally I was told the account would close on 8th January and some packaging would be sent so I could return the box and modem to Virgin Media. Fair enough, I thought.

I was travelling before Christmas, but noticed when I got back that Virgin Media had made a number of attempt to phone me while I was away. Eventually they phoned when I was in. An operative told me he wanted to discuss “changes to my account” and asked for my password. I said there was nothing to discuss as I had cancelled it. He persisted. I put the phone down. When I got back from a Christmas break in Newcastle the same thing happened again, with the same response. Then again the same day. Then again. The third time it happened in the same morning, I’m afraid I lost my temper and told the Virgin Media representative to fuck off. That did the trick.

Yesterday I received a bill from Virgin Media including a charge for the period 8th January to 7th February 2013, being the month after my account was supposed to be cancelled. I picked up the phone and called Virgin Media, assuming that somehow the instruction to close the account had been lost. In fact it hadn’t. The person I spoke to said “yes, your account is to be closed on 8th January”. “Then why have you billed me for the following month?”, I asked. “That’s our standard practice.” was the reply.

Standard practice? Sounds to me like theft! Assuming it would be very difficult to get money back once Virgin Media had purloined it, I immediately cancelled my Direct Debit to stop them taking the funds from my bank account. If they send me a correct bill for what I actually owe, I’ll pay it of course. But I’m never having anything to do with Virgin Media ever again.

P.S. I won’t have internet at home for a while from 8th January, so probably won’t be doing much blogging at weekends. On the other hand, I will have a lot of other things to be getting on with as I gradually relocate to Brighton by the sea…

P.P.S. Just received an email from Virgin Media with the following header…

medialogo

…which is of course exactly what I did.

Blog Feedback Questionnaire

Posted in Uncategorized on January 4, 2013 by telescoper

I’m back to work with a thump, having received delivery of my module feedback questionnaires for last term. All useful feedback, so I’m grateful for the students who bothered to fill them in and especially to those who wrote detailed textual comments. Apart from one, that is, who was apparently so gripped by apoplexy that he/she was unable to hold the pen properly – the resulting scratchings were entirely illegible.

Anyway, in the light of the students’ response to the quality of my lecturing I thought I’d try to gather feedback on the quality of my blogging. Please complete the following survey. Textual comments may be provided in the form of textual comments through the textual comment box below.

Now is the Winter of our Discontent

Posted in Literature with tags , , on January 3, 2013 by telescoper

Astronomy Look-alikes, No. 82

Posted in Astronomy Lookalikes with tags , on January 2, 2013 by telescoper

The resemblance between wacky comedian Richard Bower and Durham University astrophysicist Prof. Kenny Everett is too strong to be disguised even by a flamboyant wig. Surely there must be a family connection?

Lookalike

Science Propaganda

Posted in Science Politics, The Universe and Stuff with tags , , on January 2, 2013 by telescoper

I thought I’d do a quick rehash of an old post which is vaguely relevant to the still simmering controversy generated by the Cox-Ince editorial I blogged about before Christmas.

The legitimate interface between science and society has many levels to it. One aspect is the simple need to explain what science tells us about the world in order that people can play an informed part in our increasingly technological society. Another is that there needs to be encouragement for (especially young) people to study science seriously and to make it their career in order to maintain the supply of scientists for the future. And then there is the issue of the wider cultural implications of science, its impact on other belief-systems (such as religions) other forms of endeavour (such as art and literature) and even for government.

I think virtually all scientists would agree with the need for engagement in at least the first two of these. In fact, I’m sure most scientists would love to have the chance to explain their work to a lay audience, but not all subjects are as accessible or inspirational as, say, astronomy. Unfortunately also, not all scientists are very good at this sort of thing. Some might even be counter-productive if inflicted on the public in this way. So it seems relatively natural that some people have had more success at this activity than others, and have thus become identified as “science communicators”. Although some scientists are a bit snobby about those who write popular books and give popular talks, most of us agree that this kind of work is vital for both science and society.

Vital, yes, but there are dangers. The number of scientists involved in this sort of work is probably more limited than it should be owing to the laziness of the popular media, who generally can’t be bothered to look outside London and the South-East for friendly scientists. The broadsheet newspapers employ very few qualified specialists among their staff even on the science pages so it’s a battle to get meaningful scientific content into print in the mass media. Much that does appear is slavishly regurgitated from one of the press agencies who are kept well fed by the public relations experts employed by research laboratories and other science institutes.

These factors mean that what comes out in the media can be a distorted representation of the real scientific process. Heads of research groups and laboratories are engaged in the increasingly difficult business of securing enough money to continue their work in these uncertain financial times. Producing lots of glossy press releases seems to be one way of raising the profile and gaining the attention of funding bodies. Most scientists do this with care, but sometimes the results are ludicrously exaggerated or simply wrong. Some of the claims circulating around the time the Large Hadron Collider was switched on definitely fell into one or more of those categories. I realise that there’s a difficult balance to be struck between simplicity and accuracy, and that errors can result from over-enthusiasm rather than anything more sinister, but even so we should tread carefully if we want the public to engage with what science really is.

The Cox-Ince editorial is refreshingly clear about the limitations of science:

Science is a framework with only one absolute: all opinions, theories and “laws” are open to revision in the face of evidence. It should not be seen or presented, therefore, as a body of inviolate knowledge against which policy should be judged; the effect of this would be to replace one priesthood with another. Rather, science is a process, a series of structures that allow us, in as unbiased a way as possible, to test our assertions against Nature.

However, there is still far too much science reporting that portrays as facts  ideas and theories which have little or no evidence to support them. This isn’t science communication, it’s science propaganda and I think too many scientists go along with it. There’s a difficult balance to be struck, between engaging the public with inspirational but superficial TV programmes and explaining the intellectual struggles that science really involves.  Give the public the latter without any of the former and they’ll surely switch off!

Most worryingly is the perceived need to demonstrate black-and-white certainty over issues which are considerably more complicated than that. This is another situation where science popularisation becomes science propaganda. I’m not sure whether the public actually wants its scientists to make pronouncements as if they were infallible oracles, but the media definitely do. Scientists sometimes become cast in the role of priests, which is dangerous, especially when a result is later shown to be false. Then the public don’t just lose faith with one particular scientist, but with the whole of science.

Science is not about certainty. What it is a method for dealing rationally with uncertainty. It is a pragmatic system primarily intended for making testable inferences about the world using measurable, quantitative data. Scientists look their most arrogant and dogmatic when they try to push science beyond the (relatively limited) boundaries of its applicability and to ride roughshod over alternative ways of dealing with wider issues including, yes, religion.

I don’t have any religious beliefs that anyone other than me would recognize as such. I am also a scientist. But I don’t see any reason why being a scientist or not being a scientist should have any implications for my (lack of) religious faith. God (whatever that means) is, by construction, orthogonal to science. I’m not at all opposed to scientists talking about their religion or their atheism in the public domain. I don’t see why their opinions are of any more interest than anyone else’s in these matters, but I’m quite happy to hear them voiced.

This brings us to the question, often raised by hardline atheists, as to whether more scientists  should follow Richard Dawkins’ lead and be champions of atheism in the public domain. As a matter of fact, I agree with some of Dawkins’ agenda, such as his argument for the separation of church and state, although I don’t feel his heavy-handed use of the vitriol in The God Delusion achieved anything particularly positive (except for his bank balance, perhaps). But I don’t think it’s right to assume that all scientists should follow his example. Their beliefs are their business. I don’t think we will be much better off if we simply replace one set of priests with another. In this respect I wholeheartedly agree with Peter Higgs who has recently described Dawkins as “embarrassing”.

So there you have my plea for both public and scientists to accept that science will never have all the answers. There will always be “aspects of human experience that, even in an age of astonishing scientific advance, remain beyond the reach of scientific explanation”.

Can I have the Templeton Prize now please?

The Cox-Ince affair rumbles on..

Posted in Science Politics with tags , , on January 1, 2013 by telescoper

The Cox-Ince controversy rumbles on, apparently…

Ken's avatarOpen Parachute

Popular science presenters like Brian Cox are sometimes criticised by colleagues suffering from a bit of professional jealousy – although it’s a lot better than in the old days. I think most scientists today recognise the need for good science communication with the public – who, after all, are financing our science through the taxation system.

Brian Cox and his mate Robin Ince wrote a recent New Statesman editorial promoting a better understanding of the nature of science and its role in public decision-making (see Politicians must not elevate mere opinion over science). It made some good points – but upset some people. The jealousy this time seems to come from a few historians and sociologists – and not scientists themselves.

I think their criticism reveals an unfortunate attitude towards the scientific process, or indeed a misunderstanding of that process. Nevertheless, the debate does reveal some aspects of the…

View original post 2,382 more words

Resolution

Posted in Jazz with tags , , , , on January 1, 2013 by telescoper

Yesterday I happened to be listening to the classic album A Love Supreme made by the John Coltrane quartet in 1964. Since the second of the four “movements” (for what of a better word) of this work is called Resolution, I thought it would be a good thing to post on New Year’s Day to welcome everyone to 2013!

A Love Supreme is one of my favourite jazz albums, not only because it’s glorious music to listen to but also for its historical importance. Shortly after making this record Coltrane comprehensively changed his musical direction, abandoning many of the structures that underpinned his earlier work and adopting an approach heavily influenced by the free jazz of the likes of Ornette Coleman and, especially, Albert Ayler. Not everyone likes the music Coltrane made after he made that transition (in 1965) but having taken his earlier style to such a high peak as A Love Supreme he and the rest of the band no doubt felt they couldn’t go any further in that direction.

There are glimpses of the later freer approach in the third track, Pursuance, when the drum and saxophone interchanges between Elvin Jones and Coltrane threaten to break the regular tempo apart, and on this (the second) track Resolution, when McCoy Tyner abandons his usual single-note lines in favour of much more complex chordal improvisations. I think Coltrane’s solo on the last track, Psalm, is entirely improvised and , accompanied by Jones’ rising and falling drum rolls, it acquires a hauntingly solemn atmosphere which makes the hairs stand up on the back of my neck every time I hear it. What a fantastic drummer Elvin Jones was.

But I haven’t got time to analyse the whole album – another’s words are in any case no substitute for listening to this masterpiece yourself – so I’ll just mention that Resolution is based on an 8-bar theme that’s very reminiscent of the theme Africa featured on Africa/Brass made a couple of years earlier. To me it sounds like Coltrane is just itching to cut loose on this track. His saxophone tone has a harder edge than usual for that period, giving the piece an anguished, pleading feel. Elvin Jones is also magnificent, his polyrhythmic accents spurring Coltrane to a climactic solo.

The intensity of Resolution ignites an even more dramatic onslaught on the next track, Pursuance, basically a blues taken at a very fast tempo, before the mood changes completely for the final part, Psalm. And all this builds from the opening track, Acknowledgement, which closes with the whole group chanting the words A Love Supreme in unison to a simple four-note figure stated at the opening of the piece.

Four tracks amounting to just over 30 minutes of music, but a masterpiece by any standards.

Happy New Year!

2012 in review

Posted in Uncategorized on December 31, 2012 by telescoper

The WordPress.com stats helper monkeys prepared a 2012 annual report for this blog.

Here’s an excerpt:

About 55,000 tourists visit Liechtenstein every year. This blog was viewed about 460,000 times in 2012. If it were Liechtenstein, it would take about 8 years for that many people to see it. Your blog had more visits than a small country in Europe!

Click here to see the complete report.

A Little Bit of Gravitational Lensing

Posted in The Universe and Stuff with tags , , , , , on December 30, 2012 by telescoper

I thought I’d take a short break from doing absolutely nothing to post a quick little item about gravitational lensing. It’s been in my mind to say something about this since I mentioned it in one of the lectures I gave just before Christmas, but I’ve been too busy (actually too disorganized) to do it until now. It’s all based on a paper posted to the arXiv in December which was led by Jo Woodward (née Short) who did her PhD with me in Cardiff and is now in a postdoctoral research position in Durham (which is in the Midlands). The following pictures were take from her paper.

This figure shows the geometry of a gravitational lens system: light from the source S is deflected by the gravitational potential of the lens L so that an image I appears at a position on the sky which is different from the actual position when viewed by the observer O:

lensing_1
There’s a critical radius (which depends on the mass and density profile of the lens) at which this can lead to the formation of multiple images of the source. Even if multiple images are not resolved, lensing results in an increase in the apparent brightness of the source.

A great deal of cosmological information can be gleaned statistically from lensing  with even limited knowledge of the properties of the source and lens populations and with incomplete information about e.g. the actual angular deflection produced by the lens or the lens mass. To illustrate this, just consider the expression for the differential optical depth to lensing (related to the probability that a source at redshift z_s is lensed by an object at redshift z_l
lensing_2

The first two terms are cosmological, accounting geometrical and expansion effects. Roughly speaking, the larger the volume out to a given redshift the higher the probability is that a given source will be lensed. The third term involves the mass function of lens systems. In the framework of the standard cosmological model this can be computed using Press-Schechter theory or one of the variations thereof. According to current understanding, cosmological structures (i.e. galaxies and clusters of galaxies) form hierarchically so this mass function changes with redshift, with fewer high mass objects present at high redshift than at low redshift, as represented in this picture, in which masses are given in units of solar masses, the colour-coding representing different redshifts:
lensing_3

The last term represents the lensing cross-section of an object with a given mass. This depends on the internal structure of the lens – an object in which the mass is highly concentrated produces  lensing effects radically different from one that isn’t. Two simple models for the mass distribution are the singular isothermal sphere (SIS) and the Navarro-Frenk-White profile (NFW). The latter is thought (by some) to represent the distribution of cold dark matter in haloes around galaxies and clusters which is more diffuse than that of the baryonic material because it can’t dissipate energy which it needs to do to fall into the centre of the object. The real potential of a galaxy in its central regions could be more like the SIS profile would predict, however, because baryons outweigh dark matter there.

Now time for a bit of historical reminiscence. In 1997 I published a book with George Ellis in which we analysed the evidence available at the time relating to the density of matter in the Universe. It was a little bit controversial at the time, but it turns out we were correct in concluding that the density of matter was well below the level favoured by most theorists i.e. only about 20-30% of the critical density. However we did not find any compelling evidence at that time for a cosmological constant (or, if you prefer, dark energy). Indeed one of the strongest upper limits on the cosmological constant came from gravitational lensing measurements, or rather the dearth of them.

The reason for this negative conclusion was that, for a fixed value of the Hubble constant,  in the presence of a cosmological constant the volume out to a given redshift is much larger than if there is no cosmological constant. That means the above integral predicts a high probability for lensing. Surveys however failed to turn up large numbers of strongly-lensed objects, hence the inference that the universe could not be dominated by a cosmological constant. This is, of course, assuming that the other terms in the integral are well understood and that the reason significant numbers of lensed systems weren’t found wasn’t just they are tricky to identify…

Meanwhile, huge advances were made in other aspects of observational cosmology that established a standard cosmological model in which the cosmological constant makes up almost 75% of the energy budget of the Universe.

Now, 15 years later on, enter the Herschel Space Observatory, which turns out to be superb at identifying gravitational lenses.  I posted about this here, in fact. Working in the far-infrared makes it impossible to resolve multiple images with Herschel – even with a 3.5m mirror in space, λ/D isn’t great for wavelengths of 500 microns! However, the vast majority of sources found during the Herschel ATLAS survey with large fluxes at this wavelengths can be identified as lenses simply because their brightness tells us they’ve probably been magnified by a lens. Candidates can then be followed up with other telescopes on the ground.  A quick look during the Science Demonstration Phase of Herschel produced the first crop of firmly identified gravitational lens systems published in Science by Negrello et al..  When the full data set has been analysed there should be hundreds of such systems, which will revolutionize this field.

To see the potential (no pun intended) of this kind of measurement, take a look at these five systems from the SDP set:

lensing_4

These systems have measured (or estimated) source and lens redshifts. What is plotted is the conditional probability of a lens at some particular lens redshift, given the source redshift and the fact that strong lensing has occurred. Curves are given for SIS and NFW lens profiles and everything else is calculated according to the standard cosmological model. The green bars represent the measured lens redshifts.  It’s early days, so there are only five systems, but you can already see that they are pointing towards low lens redshifts, favouring NFW over SIS;  the yellow and light blue shading represents regions in which 68% of the likelihood lies.  These data don’t strongly prefer one model over the other, but with hundreds more, and extra information about at least some of the lens systems (such as detailed determinations of the lens mass from deflections etc) we should be able  to form more definite conclusions.

Unfortunately the proposal I submitted to STFC to develop a more detailed theoretical model and statistical analysis pipeline (Bayesian, of course) wasn’t funded. C’est la vie. That probably just means that someone smarter and quicker than me will do the necessary…

R.I.P. Tony Greig

Posted in Cricket with tags , , , on December 29, 2012 by telescoper

Shocked and saddened by news of the death of former England cricket captain Tony Greig, at the age of only 66.  He was a controversial character, but a fine all-rounder and skipper as a player, and also part of the finest comedy double-act in cricket history (with Geoffrey Boycott) when he became a commentator: