Seeing Dark Matter..

Posted in The Universe and Stuff with tags , , , , on November 13, 2010 by telescoper

I found this intruiging and impressive image over at Cosmic Variance (there’s also a press release at the Hubble Space Telescope website with higher resolution images). It shows the giant cluster of galaxies Abell 1689 with, superimposed on it, a map of the matter distribution as reconstructed from the pattern of distortions of background galaxy images caused by gravitational lensing.

This picture confirms the existence of large amounts of dark matter in the cluster – the mass distribution causing lensing quite different from what you can see in the luminous matter – but it also poses a problem, in that the matter is much more concentrated in the centre of the cluster than current theoretical ideas seem to suggest it should be…

You can find the full paper here.


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Thought for the Day

Posted in Science Politics with tags , on November 12, 2010 by telescoper

No time for a lengthy post today, as I’m off to London for (at least part of ) meeting at the Royal Astronomical Society.

However, yesterday I came across the following quote from John Womersley, Director of Science Programmes at the Science and Technology Facilities Council:

“The quickest way to get out of the economic dilemmas is to be able to evolve scientifically and that requires a scientifically trained workforce,” Womersley explained, adding that only 20 to 30 percent of astronomy is about understanding the universe. “The rest is about training people.”

Apparently this sort of message “works with government” and “intellectual purity” doesn’t.

I find this a profoundly uninspiring message for those of us who happen to think astronomy is worth doing for its own sake, i.e. that astronomy has intrinsic scientific value. John Womersley might well be right in saying that the Treasury isn’t interested in “pure science”, but where did the figure of 20 to 30 percent come from, and what does this say about the sinking status of astronomical research in the UK’s system of science funding? I fear the worst for British astronomy over the next few years, as the funding squeeze on STFC takes hold if this is what senior STFC managers really think about astronomy.

Isn’t there anyone at STFC prepared to champion the science, rather than pushing the spin-offs and training angle all the time? The latter are important, but they add to, rather than replace, the case that the pursuit of scientific knowledge is vital for our intellectual and cultural development as a society.

Another thing to point out is that STFC doesn’t actually train anyone. All the training John talks about is done by university staff. So if >70% of astronomy is about training then surely that’s an argument for a huge increase in university research grants, fellowships and studentships? Or is the idea that STFC provides the telescopes and universities provide the training in exchange for being allowed to use them?

And isn’t funding, say, the ESO subscription a staggeringly expensive way of training folk for industry or commerce? In any case the biggest barrier in the UK to having a scientifically educated workforce is actually the lack of physics teachers in state schools and the very poor quality of the science part of the national curriculum. Won’t the Treasury spot that fallacy?

It may of course be that many of you share John Womersley’s view. I’d be interested in the results of the following straw poll


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Observances

Posted in Biographical, History with tags on November 11, 2010 by telescoper

Just for the record, I sneaked back to my office a little early from this morning’s coffee break, closed the door, and at 11am precisely stood alone for the two minutes’ silence that marks Armistice Day. Cardiff University organised a collective Act of Remembrance in which the two minutes’ silence was preceded by prayers and to which all staff and students were invited. I am, however, not a Christian and the religious dimension means nothing to me, so I did what I prefer to do as long as circumstances permit and marked the occasion on my own.

As I stood in my office looking out over the road, I could see a small group of young people, presumably students, standing outside in silence with their heads bowed. I don’t really understand why but a solitary tear fell from my eye as I watched them.

At 11.02 I went back to work.

Lest we forget.


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The New Scheme for STFC Research Grants

Posted in Science Politics with tags , on November 11, 2010 by telescoper

Quickly donning my Community Service hat, I thought I’d pass on a little bit of news from the Science and Technology Facilities Council (STFC) to my avid readership (both of them).

You may recall that a few months ago STFC sent out a consultation document to its “community”, in which departments were asked to comment on three proposals for a new system of research grant funding.

Well, the Committee responsible for considering this issue has now reported back in a lengthy document that can be found here.

So which of the three options are they recommending, do I hear you ask? Well, actually, none of them.

What they are in fact recommending, in essence, is that in future there will only be a single three-year “consolidated” grant per department in each discipline (e.g. particle physics or astronomy). The security of the existing (five-year) rolling grants will all but vanish, although a vestigial element of this will be retained by allowing some part of the three-year allocation to be spent over a 4 year period. What will also be lost is the flexibility of the current standard 3-year grants to provide a small amount of funding for novel ideas by individual researchers. In the new system, all scientists in a given department will be allowed to apply only once every three years.

The proposal clearly sounds the death knell for any form of “responsiveness” in grant funding from STFC, further strengthening the impression (which has been growing for many years) the Executive wishes to impose a rigid top-down management on all its science programmes.

It looks to me like they have combined the least attractive aspects of the three proposals into a single scheme that is considerably worse, from the point of view of delivering science, than the sum of its parts. Nevertheless, STFC Council has endorsed the new proposal and it looks like it is now going to be implemented.

One might wonder what was the point of consulting on three alternatives and then implementing something completely different to all of them, but the answer to that appears to be simply the desire to save administrative costs.

I’m sure there’ll be comments and reaction to this announcement, so please feel free to add yours through the box below!


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Our Place in the Universe

Posted in Biographical, The Universe and Stuff with tags , , on November 10, 2010 by telescoper

Just a quick post to plug a forthcoming lecture entitled Our Place in the Universe by my former PhD supervisor, Professor John D. Barrow.

This lecture is one of a series held jointly between the University of Bath and the William Herschel Society. In fact, I gave the corresponding lecture last year on The Cosmic Web, a podcast of which is available here. It doesn’t seem like a whole year has passed since I blogged about that event!

John Barrow’s lecture will take place at 7pm on Thursday 11th November, at the Claverton Campus of the University of Bath. For further details, see the link above. I realise that it’s a bit far for local Cardiff people to get there and back in the evening, but there might be a few readers of this blog who can make it there. John is an excellent public speaker and I’d encourage anyone who can go to do so, as I’m sure it will prove very rewarding.


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Business Class

Posted in Biographical, Science Politics with tags , , , , , on November 9, 2010 by telescoper

I’d never heard of Cardiff Business Club until Friday afternoon, when I received a message that they were hosting a lecture by Dr Lyndon Evans, the Director of the Large Hadron Collider experiment at CERN in Geneva, followed by a dinner, and had sent a bunch of invitations to the School of Physics & Astronomy at Cardiff University, where I work.

Given the short notice it was a bit of a scramble to get a group together, but in the end eight of us – 3 staff and 5 students – headed off in taxis yesterday to the swish St David’s Hotel in Cardiff Bay for the welcoming reception.

Earlier in the day I’d been in contact with Alun  Davies, the Secretary of Cardiff Business Club, who had asked me  if I would deliver the vote of thanks at the end of Dr Evans’ lecture.  Naturally, I agreed to do the honours. I’m not actually a particle physicist, of course, but I was the closest thing available. This all meant that, instead of joining my colleagues at the reception, I went off to meet the speaker and various officers of the club in a private lounge where we were plied with drinks and canapés. As well as meeting Lyn Evans, I also got the chance to chat with the Club Chairman, legendary former rugby international Gerald Davies who is an extremely friendly and charming bloke.

Thence it was downstairs to the lecture, during which I sat on the platform, facing the audience, from where it was extremely difficult to see the speaker’s slides. It was a 30-minute overview of the science, technology, and even politics behind the LHC, which went down extremely well. I remember this quote in particular

The greatest economic benefits of scientific research have always resulted from advances in fundamental knowledge rather than the search for specific applications.

It’s  particularly interesting, in the light of  government suggestions that we should  focus science funding more on applied sciences and technology, to note that this remark was made by Margaret Thatcher.

At the end I did my best to keep my vote of thanks as brief as possible – brevity has never been my strong suit, I’m afraid – and we then went off to dinner, with me rejoining the physics crowd at their table in a far-flung corner of the room.

Not surprisingly, the dinner turned out to be quite a formal affair – preceded by grace and followed by the loyal toast – which I think made some of our party feel a little bit uncomfortable, but at least it was all free! The room was dominated by men in suits who all looked like they were used to going everywhere Business Class. We academics usually travel by  Economy Class only.

Proceedings drew to a close quite early, at 10pm. Unfortunately, the temptation to adjourn to the pub for a “quick drink” proved too strong to resist.

I got home at 2.30am.


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To the Warmongers

Posted in History, Poetry, Politics with tags , , , on November 8, 2010 by telescoper

As we approach Remembrance Sunday (which this year lies on 14th November) I find myself once again wearing a poppy on my coat lapel, and having once again to explain this to those I meet in the department and elsewhere who don’t approve. I’ve already said everything I think I need to on this in posts last year and the year before, so I won’t repeat myself at length here.

I am aware (and acutely sensitive to) the danger that the wearing of a poppy might be mistaken for support for militarism and that many of our politicians would like to manipulate the meaning of this symbol in precisely that way for their own ends. Nevertheless, I will wear one and will observe the two minutes’ silence on Thursday too. Why? Lest we forget, that’s why…

But instead of debating this again, I will  post the following poem and letter, both of which were written by Siegfried Sassoon.

The poem is called the To the Warmongers:

I’m back again from hell
With loathsome thoughts to sell;
Secrets of death to tell;
And horrors from the abyss.
Young faces bleared with blood,
Sucked down into the mud,
You shall hear things like this,
Till the tormented slain
Crawl round and once again,
With limbs that twist awry
Moan out their brutish pain,
As for the fighters pass them by.
For you our battles shine
With triumph half-divine;
And the glory of the dead
Kindles in each proud eye.
But a curse is on my head,
That shall not be unsaid,
And the wounds in my heart are red,
For I have watched them die.

The astonishing letter below was written by Siegfried Sassoon in July 1917, and was subsequently read out in the House of Commons. Sassoon narrowly escaped court martial for treason.

It’s worth noting the last two paragraphs:

I have seen and endured the sufferings of the troops and I can no longer be a party to prolonging these sufferings for ends which I believe to be evil and unjust. I am not protesting against the conduct of the war, but against the political errors and insincerities for which the fighting men are being sacrificed.

On behalf of those who are suffering now, I make this protest against the deception which is being practised upon them; also I believe it may help to destroy the callous complacency with which the majority of those at home regard the continuance of agonies which they do not share and which they have not enough imagination to realise.

The tragedy is that these words could equally well have been written about Afghanistan 2010 rather than France or Belgium 1917. The sight of Tony Blair wearing a poppy at the Cenotaph is one that filled me with nausea, but his hypocrisy makes it more, not less, important to hang on to the true meaning. Lest we forget. Nowadays, though, I don’t really “wear my poppy with pride”, but with something rather closer to shame.


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Uncertainty

Posted in The Universe and Stuff with tags , on November 7, 2010 by telescoper

At the risk of turning this blog into a Feynman-fest – although I don’t think that would be such a bad thing, as a matter of fact – I couldn’t resist posting this little clip as a follow up to my previous one. In it he talks about a subject that has been a recurring motif on this blog – the importance of knowing when not to be certain.


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Stardust

Posted in Jazz, The Universe and Stuff with tags , , on November 7, 2010 by telescoper

Stellar stuff. Tune by Hoagy Carmichael.  Alto saxophone by Sonny Stitt. Images by various artists astronomers.

Sometimes I wonder why I spend
these lonely nights dreaming of a song
The melody haunts my reverie,
and I am once again with you
When our love was new
and each kiss an inspiration
But that was long ago,
now my consolation is in the stardust of a song.

Beside a garden wall,
when stars are bright,
you are in my arms
The nightingale tells his fairy tale
Of paradise where roses grew
Though I dream in vain,
in my heart it will remain
My stardust melody,
The memory of love’s refrain


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A New Theory of Dark Matter

Posted in Science Politics, The Universe and Stuff with tags , , , , , , on November 6, 2010 by telescoper

Since this week has seen the release of a number of interesting bits of news about particle physics and cosmology, I thought I’d take the chance to keep posting about science by way of a distraction from the interminable discussion of  funding and related political issues. This time I thought I’d share some of my own theoretical work, which I firmly believe offers a viable alternative to current orthodox thinking in the realm of astroparticle physics.

As you probably know, one of the most important outstanding problems in this domain is to find an explanation of dark matter, a component of the matter distribution of the Universe which is inferred to exist from its effects on the growth of cosmic structures but which is yet to be detected by direct observations. We know that this dark matter can’t exist in the form of familiar atomic material (made of protons, neutrons and electrons) so it must comrpise some other form of matter. Many candidates exist, but the currently favoured model is that it is made of weakly interacting massive particles (WIMPs) arising in particle physics theories involving supersymmetry, perhaps the fermionic counterpart of the gauge bosons of the standard model, e.g. the photino (the supersymmetric counterpart of the photon).

However, extensive recent research has revealed that this standard explanation may in fact be incorrect and circumstantial evidence is mounting that supports a  radically different scenario. I am now in a position to reveal the basics of a new theory that accounts for many recent observations in terms of an alternative hypothesis, which entails the existence of a brand new particle called the k-Mason.

Standard WIMP dark matter comprises very massive particles which move very slowly, hence the term Cold Dark Matter or CDM, for short.  This means that CDM forms structures very rapidly and efficiently, in a hierarchical or “bottom-up” fashion. This idea is at the core of the standard “concordance” cosmological model.

However, the k-Mason is known to travel such huge distances at such high velocity in random directions between its (rare) encounters that it not only inhibits the self-organisation of other matter, but actively dissipates structures once they have been formed. All this means that structure formation is strongly suppressed and can only happen in a “top-down” manner, which is extremely inefficient as it can only form small-scale structures through the collapse of larger ones. Astronomers have compiled a huge amount of evidence of this effect in recent years, lending support to the existence of the k-Mason as a dominant influence  (which is of course entirely at odds with the whole idea of concordance).

Other studies also provide pretty convincing quantitative evidence of the large mean free path of the k-Mason.

Although this new scenario does seem to account very naturally for the observational evidence of  collapse and fragmentation gathered by UK astronomers since 2007, there are still many issues to be resolved before it can be developed into a fully testable theory. One difficulty is that the k-Mason appears to be surprisingly stable, whereas most theories suggest it would have vanished long before the present epoch. On the other hand, it has also been suggested that, rather than simply decaying, the k-Mason may instead  transform into some other species with similar properties; suggestions for alternative candidates emerging from the decay of the  k-Mason  are actively being sought and it is hoped this process will be observed definitively within the next 18 months or so.

However the biggest problem facing this idea is the extreme difficulty of  detecting the k-Mason  at experimental or observational facilities. Some scientists have claimed evidence of its appearance at various laboratories run by the UK’s Science and Technology Facilities Council (STFC), as well as at the Large Hadron Collider at CERN, but these claims remain controversial: none has really stood up to detailed scrutiny and all lack independent confirmation from reliable witnesses. Likewise there is little proof of the presence of k-Mason at any ground-based astronomical observatory, which has led many astronomers to conclude that  only observations done from space will remain viable in the longer term.

So, in summary, while the k-Mason remains a hypothetical entity, it does furnish a plausible theory that accounts, in a broad-brush sense, for many disparate phenomena. I urge particle physicists, astronomers and cosmologists to join forces in the hunt for this enigmatic object.

NOTE ADDED IN PROOF: The hypothetical “k-Mason” referred to in this article is not to be confused with the better-known “strange” particle the  k-Meson.


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