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Back to the Drawing Board

Posted in Art, Education, The Universe and Stuff with tags , , , , , , , , , on August 30, 2011 by telescoper

I came across a press release this morning which contains the following

More should be done to encourage students to use their drawing skills in science education, researchers at The University of Nottingham say.

In a paper being published in Science this week, academics say that although producing visualisations is key to scientific thinking, pupils are often not encouraged to create their own drawings to develop and demonstrate their understanding.

In the paper the authors, led by Dr Shaaron Ainsworth in the University’s School of Psychology and Learning Sciences Research Institute, said: “Scientists do not use words only but rely on diagrams, graphs, videos, photographs and other images to make discoveries, explain findings, and excite public interest.

In the light of this I thought it would be topical to post an updated version of an old piece I wrote on the theme of sketching. This is quite a strange subject for me to have picked pick because drawing is something I’m completely useless at, but I hope you’ll bear with me and hopefully it will make some sense in the end. I always thought that drawing was an important and neglected aspect of education, but I hadn’t until today any solid research to back it up!

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What  spurred me on to think about this subject was the exhibit I was  involved with for the  Architecture Biennale in Venice as part of a project called Beyond Entropy organized by the Architectural Association School of Architecture. In the course of researching this project I came across this image of the Moon as drawn by Galileo

This led to an interesting discussion about the role of drawings like this in science. Of course  the use of sketches for the scientific representation of images has been superseded by photographic techniques, initially using film and more recently by digital techniques. The advantage of these methods is that they are quicker and also more “objective”. However, there are still many amateur astronomers who make drawings of the Moon as well as objects such as Jupiter and Saturn (which Galileo also drew). Moreover there are other fields in which experienced practioners continue to use pencil drawings in preference to photographic techniques. Archaeology provides many good examples, e.g.

The reason sketching still has a role in such fields is not that it can compete with photography for accuracy or objectivity but that there’s something about the process of sketching that engages the sketcher’s brain in a  way that’s very different from taking a photograph. The connection between eye, brain and hand seems to involve a cognitive element that is extremely useful in interpreting notes at a later date. In fact it’s probably their very subjectivity that makes them useful.  A thicker stroke of the pencil, or deliberately enhanced shading, or leaving out seemingly irrelevant detail, can help pick out  features that seem to the observer to be of particular significance. Months later when you’re trying to write up what you saw from your notes, those deliberate interventions against objectivity will take you back to what you  saw with your mind, not just with your eyes.

It doesn’t even matter whether or not you can draw well. The point isn’t so much to explain to other people what you’ve seen, but to record your own interaction with the object you’ve sketched in a way that allows you to preserve something more than a surface recollection.

You might think this is an unscientific thing to do, but I don’t think it is. The scientific process involves an interplay between objective reality and theoretical interpretation and drawing can be a useful part of this discourse. It’s as if the pencil allows the observer to interact with what is observed, forming a closer bond and probably a deeper level of understanding patterns and textures. I’m not saying it replaces a purely passive recording method like photography, but it can definitely help it.

I have not a shred of psychological evidence to back this up, but I’d also assert that sketching is very good for the learning process too.  Nowadays we tend to give out handouts of diagrams involved in physics, whether they relate to the design of apparatus or the geometrical configuration of a physical system. There’s a reason for doing this – they take a long time to draw and there’s a likelihood students will make mistakes copying them down. However, I’ve always  found that the only way to really take in what a diagram is saying is to try to draw it again myself. Even if the level of draftsmanship is worse, the level of understanding is undoubtedly better.Merely looking at someone else’s representation of something won’t give your brain as a good a feeling for what it is trying to say  as you would get if you tried to draw it yourself.

Perhaps what happens is that simply looking at a diagram only involves the connection between eye and brain. Drawing a copy requires also the connection between brain and hand. Maybe  this additional connection brings in additional levels of brain functionality. Sketching iinvolves your brain in an interaction that is different from merely looking.

The problem with excessive use of handouts – and this applies not only to figures  but also to lecture notes – is that they turn teaching into a very passive process. Taking notes in your own hand, and supplementing them with your own sketches – however scribbly and incomprehensible they may appear to other people – is  a much more active way to learn than collecting a stack of printed notes and meticulously accurate diagrams. And if it was good enough for Galileo, it should good enough for most of us!

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It’s not a planet. It’s a white dwarf. (via Matt Burleigh’s Blog)

Posted in Astrohype, The Universe and Stuff with tags , , , , on August 27, 2011 by telescoper

When is a planet made of diamond not a planet made of diamond?

Perhaps when it’s a White Dwarf?

Perhaps when there’s not a shred of evidence that it’s actually made of diamond?

Yesterday Science announced the amazing discovery of an incredibly dense object that appears to be made of a crystalline form of carbon: possibly, ultra-dense diamond (Bailes et al. 2011, Science, DOI: 10.1126/science.1208890). The object orbits a recently-discovered pulsar, PSR J1719-1438, every two hours and ten minutes. It has a slightly higher mass than Jupiter (technically, its minimum mass), but the lack of evidence for direct interaction w … Read More

via Matt Burleigh’s Blog

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Cosmology

Posted in Jazz, The Universe and Stuff with tags , , , , , on August 24, 2011 by telescoper

I don’t know why it’s taken me so long to get around the posting this piece, but I suppose it’s better late than never. It’s by the brilliant trio led by Paul Motian (drums) and featuring Joe Lovano on tenor sax with Bill Frisell on guitar. The album it’s taken from is called Trioism,  which was recorded in 1993. I’ve picked this particular track to put up as a taster because it’s entitled Cosmology, which just happens to be my day job…

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JWST: Over and Out?

Posted in Science Politics, The Universe and Stuff with tags , , , , on August 23, 2011 by telescoper

News filtered through recently that the cost of the James Webb Space Telescope, which is already  threatened with cancellation owing to cuts in NASA’s budget, is now estimated to be around $8.7 billion dollars, about $2.2 billion higher than previous figures. In fact about a decade ago, when I was a lad, and chair of the old PPARC Astronomy Advisory Panel, the price tag of  the NGST (Next Generation Space Telescope), as it was then called, was put at significantly less than one billion dollars.

The implications of cancelling JWST are profound on both sides of the Atlantic. As Mark McCaughrean explains in detail over on the e-astronomer, the European Space Agency has already made a substantial investment in JWST and planned future contributions include the launch and substantial operating costs. The instrument development is nearly finished, but whether there will actually be a telescope to put instruments on remains to be seen. It’s clear that this, together with previous unilateral decisions by NASA, is putting some strain on the relationship with ESA.

There were many who reacted to the initial suggestion that JWST should be cancelled by arguing that it was mere political posturing by Republicans in the House of Representatives and that it could and would be reversed if appropriate campaigning took place. To this end there has been, e.g.,  a letter to the White House Science Advisor (here for non-US astronomers and there for US ones). There’s also been a letter of support from the President of the Royal Astronomical Society. NASA’s administrators have also apparently come up with a plan to divert funds from other projects to support it. These efforts notwithstanding I get the distinct feeling that cancellation of JWST is a very real prospect and it goes without saying that the chances of avoiding it are not helped by  the increased estimated expense.

I’ve talked about this to a number of astronomers and cosmologists over the summer and found very mixed views not only about  (a) whether JWST will be cancelled or not but also about (b) whether it should be cancelled or not. Even astronomers have expressed exasperation with the spiralling cost of JWST and pointed out that if we had known a decade ago that it would take so long and involve such an outlay then it would never have gone ahead in the first place.

So let me try a straw poll:

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Is Space Expanding?

Posted in The Universe and Stuff with tags , , , , , , , , , on August 19, 2011 by telescoper

I think I’ve just got time for a quick post this lunchtime, so I’ll pick up on a topic that rose from a series of interchanges on Twitter this morning. As is the case with any interesting exchange of views, this conversation ended up quite some distance from its starting point, and I won’t have time to go all the way back to the beginning, but it was all to do with the “expansion of space“, a phrase one finds all over the place in books articles and web pages about cosmology at both popular and advanced levels.

What kicked the discussion off was an off-the-cuff humorous remark about the rate at which the Moon is receding from the Earth according to Hubble’s Law; the answer to which is “very slowly indeed”. Hubble’s law is v=H_0 d where v is the apparent recession velocity and d the distance, so for very small distance the speed of expansion is tiny. Strictly speaking, however, the velocity isn’t really observable – what we measure is the redshift, which we then interpret as being due to a velocity.

I chipped in with a comment to the effect that Hubble’s law didn’t apply to the Earth-Moon system (or to the whole Solar System, or for that matter to the Milky Way Galaxy or to the Local Group either) as these are held together by local gravitational effects and do not participate in the cosmic expansion.

To that came the rejoinder that surely these structures are expanding, just very slowly because they are small and that effect is counteracted by motions associated with local structures which “fight against” the “underlying expansion” of space.

But this also makes me uncomfortable, hence this post. It’s not that I think this is necessarily a misconception. The “expansion of space” can be a useful thing to discuss in a pedagogical context. However, as someone once said, teaching physics involves ever-decreasing circles of deception, and the more you think about the language of expanding space the less comfortable you should feel about it, and the more careful you should be in using it as anything other than a metaphor. I’d say it probably belongs to the category of things that Wolfgang Pauli would have described as “not even wrong”, in the sense that it’s more meaningless than incorrect.

Let me briefly try to explain why. In cosmology we assume that the Universe is homogeneous and isotropic and consequently that the space-time is described by the Friedmann-Lemaître-Robertson-Walker metric, which can be written

ds^{2} = c^{2} dt^{2}-a^{2}(t) d\sigma^{2}

in which d\sigma^2 describes the (fixed) geometry of a three-dimensional homogeneous space; this spatial part does not depend on time. The imposition of spatial homogeneity selects a preferred time coordinate t, defined such that observers can synchronize watches according to the local density of matter – points in space-time at which the matter density is the same are defined to be at the same time.

The presence of the scale factor a(t) in front of the spatial 3-metric allows the overall 4-metric to change with time, but only in such a way that preserves the spatial geometry, in other words the spatial sections can have different scales at different times, but always have the same shape. It’s a consequence of Einstein’s equations of General Relativity that a Universe described by the FLRW metric must evolve with time (at least in the absence of a cosmological constant). In an expanding universe a(t) increases with t and this increase naturally accounts for Hubble’s law, with  H(t)=\dot{a}/a but only if you define velocities and distances in the particular way suggested by the coordinates used.

So how do we interpret this?

Well, there are (at least) two different interpretations depending on your choice of coordinates.  One way to do it is to pick spatial coordinates such that the positions of galaxies change with time; in this choice the redshift of galaxy observed from another is due to their relative motion. Another way to do it is to use coordinates in which the galaxy positions are  fixed; these are called comoving coordinates.  In general relativity we can switch between one view and the other and the observable effect (i.e. the redshift) is the same in either.

Most cosmologists use comoving coordinates (because it’s generally a lot easier that way), and it’s this second interpretation that encourages one to think not about things moving but about space itself expanding. The danger with that is that it sometimes leads one to endow “space” (whatever that means) with physical attributes that it doesn’t really possess. This is most often seen in the analogy of galaxies being the raisins in a pudding, with “space” being the dough that expands as the pudding cooks taking the raisins away from each other. This analogy conveys some idea of the effect of homogeneous expansion, but isn’t really right. Raisins and dough are both made of, you know, stuff. Space isn’t.

In support of my criticism I quote:

 Many semi-popular accounts of cosmology contain statements to the effect that “space itself is swelling up” in causing the galaxies to separate. This seems to imply that all objects are being stretched by some mysterious force: are we to infer that humans who survived for a Hubble time [the age of the universe] would find themselves to be roughly four metres tall? Certainly not….In the common elementary demonstration of the expansion by means of inflating a balloon, galaxies should be represented by glued-on coins, not ink drawings (which will spuriously expand with the universe).

(John Peacock, Cosmological Physics, p. 87-8). A lengthier discussion of this point, which echoes some of the points I make below, can be found here.

To get back to the original point of the question let me add another quote:

A real galaxy is held together by its own gravity and is not free to expand with the universe. Similarly, if [we talk about] the Solar System, Earth, [an] atom, or almost anything, the result would be misleading because most systems are held together by various forces in some sort of equilibrium and cannot partake in cosmic expansion. If we [talk about] clusters of galaxies…most clusters are bound together and cannot expand. Superclusters are vast sprawling systems of numerous clusters that are weakly bound and can expand almost freely with the universe.

(Edward Harrison, Cosmology, p. 278).

I’d put this a different way. The “Hubble expansion” describes the motion of test particles in a the coordinate system I described above, i.e one  which applies to a perfectly homogeneous and isotropic universe. This metric simply doesn’t apply on the scale of the solar system, our own galaxy and even up to the scale of groups or clusters of galaxies. The Andromeda Galaxy (M31),  for example, is not receding from the Milky Way at all – it has a blueshift.  I’d argue that the space-time geometry in such systems is simply nothing like the FLRW form, so one can’t expect to make physical sense trying to to interpret particle motions within them in terms of the usual cosmological coordinate system. Losing the symmetry of the FLRW case  makes the choice of appropriate coordinates much more challenging.

There is cosmic inhomogeneity on even larger scales, of course, but in such cases the “peculiar velocities” generated by the lumpiness can be treated as a (linear) correction to the pure Hubble flow associated with the background cosmology.  In my view, however, in highly concentrated objects that decomposition into an “underlying expansion” and a “local effect” isn’t useful. I’d prefer simply to say that there is no Hubble flow in such objects. To take this to an extreme, what about a black hole? Do you think there’s a Hubble flow inside one of those, struggling to blow it up?

In fact the mathematical task of embedding inhomogeneous structures in an asymptotically FLRW background is not at all straightforward to do exactly, but it is worth mentioning that, by virtue of Birkhoff’s theorem,  the interior of an exactly spherical cavity (i.e. void)  must be described by the (flat) Minkowski metric. In this case the external cosmic expansion has absolutely no effect on the motion of particles in the interior.

I’ll end with this quote from the Fount of All Wisdom, Ned Wright,in response to the question Why doesn’t the Solar System expand if the whole Universe is expanding?

This question is best answered in the coordinate system where the galaxies change their positions. The galaxies are receding from us because they started out receding from us, and the force of gravity just causes an acceleration that causes them to slow down, or speed up in the case of an accelerating expansion. Planets are going around the Sun in fixed size orbits because they are bound to the Sun. Everything is just moving under the influence of Newton’s laws (with very slight modifications due to relativity). [Illustration] For the technically minded, Cooperstock et al. computes that the influence of the cosmological expansion on the Earth’s orbit around the Sun amounts to a growth by only one part in a septillion over the age of the Solar System.

The paper cited in this passage is well worth reading because it demonstrates the importance of the point I was trying to make above about using an appropriate coordinate system:

In the non–spherical case, it is generally recognized that the expansion of the universe does not have observable effects on local physics, but few discussions of this problem in the literature have gone beyond qualitative statements. A serious problem is that these studies were carried out in coordinate systems that are not easily comparable with the frames used for astronomical observations and thus obscure the physical meaning of the computations.

Now I’ve waffled on far too long so  I’ll just finally  recommend this paper entitled Expanding Space: The Root of All Evil and get back to work…

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More Cosmological Haiku

Posted in Poetry, The Universe and Stuff with tags , , , , on August 18, 2011 by telescoper

In view of my current rather hectic schedule – why else would I be up at this ungodly hour? – I thought I’d combine another bit of recycling with some audience participation. I’ve updated below the list of Haiku I posted some time ago with some new ones I’ve jotted down at random intervals over the intervening months.

How about a few Haiku of your own on themes connected to astronomy, cosmology or physics?

Don’t be worried about making the style of your contributions too authentic, just make sure they are 17 syllables in total, and split into three lines of 5, 7 and 5 syllables respectively.

Here are some of my own to get you started:

Quantum Gravity:
The troublesome double-act
Of Little and Large

Gravity’s waves are
Traceless; which does not mean they
Can never be found

The Big Bang wasn’t
So big, at least not when you
Think in decibels.

Cosmological
Constant and Dark Energy
Are vacuous names

Microwave Background
Photons remember a time
When they were hotter

Isotropic and
Homogeneous metric?
Robertson-Walker

Galaxies evolve
In a complicated way
We don’t understand

Acceleration:
Type Ia Supernovae
Gave us the first clue

Cosmic Inflation
Could have stretched the Universe
And made it flatter

Astrophysicist
Is what I’m told is my Job
Title. Whatever.

“Clusters look cool,”  said
Sunyaev and Zel’dovich,
“because they are hot”.

Gaussianity
is produced by inflation,
normally speaking.

Gravity waves are
a kind of perturbation;
they make you tensor

Bubble collisions
Leave marks in the C-M-B
To please A. Linde

This Haiku contains
“Baryon Oscillations”
in its middle line.

What should we build next:
S-K-A or E-L-T?
Or maybe neither…?

J W* S T,
(the James Webb Space Telescope);
long name, big budget

* “W” has to be pronounced “dubya” for this one to work!

Contributions welcome via the comments box. The best one gets a chance to win Bully’s star prize.

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The Hawking Paradox on BBC iPlayer

Posted in The Universe and Stuff with tags , , , on August 17, 2011 by telescoper

I just heard at lunchtime that a TV programme I was in was recently repeated on BBC4 and is consequently now available on BBC i Player, so I thought I’d advertise it on here.  I didn’t see the broadcast myself, because I scarcely watch TV these days.

The programme was originally made for the BBC TV series Horizon and first broadcast in the UK in 2005. You’ll find yours truly in a couple of places, when I was working at the University of Nottingham and had more hair. In fact I got quite a bit of stick, from some people at a certain University I used to attend, for being insufficiently reverential in my comments about Stephen Hawking but, for what it’s worth, I stand by everything I said. I do admire him enormously as a physicist, but I think his very genuine contributions are sometimes lost in the cult that has developed around him.

Anyway, I thought the programme turned out relatively well but you can watch it yourself by clicking here and form your own opinion!

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More on MacGuffins

Posted in Science Politics, The Universe and Stuff with tags , , , , , , , , on August 17, 2011 by telescoper

I’m very pressed for time this week  so I thought I’d cheat by resurrecting and updating an old post from way back when I had just started blogging, about three years ago.  I thought of doing this because I just came across a Youtube clip of the late great Alfred Hitchcock, which you’ll now find in the post. I’ve also made a couple of minor editorial changes, but basically it’s a recycled piece and you should therefore read it for environmental reasons.

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Unpick the plot of any thriller or suspense movie and the chances are that somewhere within it you will find lurking at least one MacGuffin. This might be a tangible thing, such the eponymous sculpture of a Falcon in the archetypal noir classic The Maltese Falcon or it may be rather nebulous, like the “top secret plans” in Hitchcock’s The Thirty Nine Steps. Its true character may be never fully revealed, such as in the case of the glowing contents of the briefcase in Pulp Fiction , which is a classic example of the “undisclosed object” type of MacGuffin. Or it may be scarily obvious, like a doomsday machine or some other “Big Dumb Object” you might find in a science fiction thriller. It may even not be a real thing at all. It could be an event or an idea or even something that doesn’t exist in any real sense at all, such the fictitious decoy character George Kaplan in North by Northwest.

Whatever it is or is not, the MacGuffin is responsible for kick-starting the plot. It makes the characters embark upon the course of action they take as the tale begins to unfold. This plot device was particularly beloved by Alfred Hitchcock (who was responsible for introducing the word to the film industry). Hitchcock was however always at pains to ensure that the MacGuffin never played as an important a role in the mind of the audience as it did for the protagonists. As the plot twists and turns – as it usually does in such films – and its own momentum carries the story forward, the importance of the MacGuffin tends to fade, and by the end we have often forgotten all about it. Hitchcock’s movies rarely bother to explain their MacGuffin(s) in much detail and they often confuse the issue even further by mixing genuine MacGuffins with mere red herrings.

Here is the man himself explaining the concept at the beginning of this clip. (The rest of the interview is also enjoyable, convering such diverse topics as laxatives, ravens and nudity..)

North by North West is a fine example of a multi-MacGuffin movie. The centre of its convoluted plot involves espionage and the smuggling of what is only cursorily described as “government secrets”. But although this is behind the whole story, it is the emerging romance, accidental betrayal and frantic rescue involving the lead characters played by Cary Grant and Eve Marie Saint that really engages the characters and the audience as the film gathers pace. The MacGuffin is a trigger, but it soon fades into the background as other factors take over.

There’s nothing particular new about the idea of a MacGuffin. I suppose the ultimate example is the Holy Grail in the tales of King Arthur and the Knights of the Round Table and, much more recently, the Da Vinci Code. The original Grail itself is basically a peg on which to hang a series of otherwise disconnected stories. It is barely mentioned once each individual story has started and, of course, is never found.

Physicists are fond of describing things as “The Holy Grail” of their subject, such as the Higgs Boson or gravitational waves. This always seemed to me to be an unfortunate description, as the Grail quest consumed a huge amount of resources in a predictably fruitless hunt for something whose significance could be seen to be dubious at the outset.The MacGuffin Effect nevertheless continues to reveal itself in science, although in different forms to those found in Hollywood.

The Large Hadron Collider (LHC), switched on to the accompaniment of great fanfares a few years ago, provides a nice example of how the MacGuffin actually works pretty much backwards in the world of Big Science. To the public, the LHC was built to detect the Higgs Boson, a hypothetical beastie introduced to account for the masses of other particles. If it exists the high-energy collisions engineered by LHC should reveal its presence. The Higgs Boson is thus the LHC’s own MacGuffin. Or at least it would be if it were really the reason why LHC has been built. In fact there are dozens of experiments at CERN and many of them have very different motivations from the quest for the Higgs, such as evidence for supersymmetry.

Particle physicists are not daft, however, and they have realised that the public and, perhaps more importantly, government funding agencies need to have a really big hook to hang such a big bag of money on. Hence the emergence of the Higgs as a sort of master MacGuffin, concocted specifically for public consumption, which is much more effective politically than the plethora of mini-MacGuffins which, to be honest, would be a fairer description of the real state of affairs.

Even this MacGuffin has its problems, though. The Higgs mechanism is notoriously difficult to explain to the public, so some have resorted to a less specific but more misleading version: “The Big Bang”. As I’ve already griped, the LHC will never generate energies anything like the Big Bang did, so I don’t have any time for the language of the “Big Bang Machine”, even as a MacGuffin.

While particle physicists might pretend to be doing cosmology, we astrophysicists have to contend with MacGuffins of our own. One of the most important discoveries we have made about the Universe in the last decade is that its expansion seems to be accelerating. Since gravity usually tugs on things and makes them slow down, the only explanation that we’ve thought of for this perverse situation is that there is something out there in empty space that pushes rather than pulls. This has various possible names, but Dark Energy is probably the most popular, adding an appropriately noirish edge to this particular MacGuffin. It has even taken over in prominence from its much older relative, Dark Matter, although that one is still very much around.

We have very little idea what Dark Energy is, where it comes from, or how it relates to other forms of energy we are more familiar with, so observational astronomers have jumped in with various grandiose strategies to find out more about it. This has spawned a booming industry in surveys of the distant Universe (such as the Dark Energy Survey) all aimed ostensibly at unravelling the mystery of the Dark Energy. It seems that to get any funding at all for cosmology these days you have to sprinkle the phrase “Dark Energy” liberally throughout your grant applications.

The old-fashioned “observational” way of doing astronomy – by looking at things hard enough until something exciting appears (which it does with surprising regularity) – has been replaced by a more “experimental” approach, more like that of the LHC. We can no longer do deep surveys of galaxies to find out what’s out there. We have to do it “to constrain models of Dark Energy”. This is just one example of the not necessarily positive influence that particle physics has had on astronomy in recent times and it has been criticised very forcefully by Simon White.

Whatever the motivation for doing these projects now, they will undoubtedly lead to new discoveries. But my own view is that there will never be a solution of the Dark Energy problem until it is understood much better at a conceptual level, and that will probably mean major revisions of our theories of both gravity and matter. I venture to speculate that in twenty years or so people will look back on the obsession with Dark Energy with some amusement, as our theoretical language will have moved on sufficiently to make it seem irrelevant.

But that’s how it goes with MacGuffins. Even the Maltese Falcon turned out to be a fake in the end.

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DEUS

Posted in Cosmic Anomalies, The Universe and Stuff with tags , , , on August 12, 2011 by telescoper

Well, I’m back home from Copenhagen after a very interesting and stimulating workshop called “DEUS” (subtitled “Current and Future Challenges of the Dark and Early Universes”). I just thought I’d post a brief message to thank the organizers for inviting me and for arranging such an interesting and varied programme, and especially for giving so many young researchers the chance to give talks (as well as some old farts like me).

Although I’d originally planned to talk about something else, I evenually decided to do a variation on the theme of cosmic anomalies, a topic I’ve blogged about at various times over the past couple of years. In a nutshell this was a quick overview of various features of the observed universe that seem to suggest departures from the standard “Lambda-CDM”  (or LCDM, for short) cosmological model, including the famous WMAP Cold Spot, the Axis of Evil, and various other statistical hints of anomalous behaviour in present-day observations.

To add a bit of audience participation I gave those attending my talk the chance to vote on what they thought about these – I was genuinely interested to see what this particular audience felt about whether the standard model is threatened or not.  I asked specifically about these in order to exclude other niggling worries people might have about LCDM from other astrophysical arguments, such as galaxy formation. Anyway, I thought it might be fun to repeat the poll here, so feel free to add your vote here:

As for the results of the vote during my presentation, I was somewhat surprised to see a roughly equal division between A and B, but there were even a few in C. I had assumed the vast majority would vote “A”….

Anyway, thanks again to the organizers of a fun meeting. That’s three trips to Copenhagen in as many months. I guess it will be a while before I go back again. 😦

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Art in the Afternoon

Posted in Art, The Universe and Stuff with tags , , , , , , on August 10, 2011 by telescoper

Just a quick blogette to mention that yesterday the workshop participants here in Copenhagen went on an excursion to the Louisiana Museum of Modern Art, which is just north of Copenhagen.

This is an extremely interesting museum to visit at any time, not just for the temporary exhibitions which at present include the architecturally-themed Living and some wonderful drawings made by David Hockney using his iPad; the latter almost made me want to go out and buy one.

There’s also a fine permanent collection, including many wonderful  sculptures by Alberto Giacometti :
and several by Henry Moore standing (or rather reclining) in the grounds:

What’s really great about Louisiana though is its relaxed informal atmosphere; kids are encouraged to play around (and sometimes in) the scupltures, there is lots of green space to relax in, and you are welcome even to swim in the sea, although I didn’t because I didn’t have my bathing costume with me. Many consider modern art and its galleries to be a bit pretentious, but that couldn’t be further than the truth for this place. I’ll also add that it was very busy indeed so is obviously extremely popular.

For those of you not so interested in Modern Art (which actually seemed to the case for many of my dining companions last night), there is a strong astronomical connection with this place because it offers a view of the Island of Hven on which Tycho Brahe established a famous observatory Uraniborg.

I’ve been to Louisiana many times but have never taken the short boat trip out to Hven, largely because there’s nothing much of the observatory left. Apparently the locals were squeezed mercilessly for taxes to pay for the running costs of Tycho’s observatory, with the result that by the time Brahe left in 1597 the residents of Hven were thoroughly fed up with him and tore the whole thing down.

The moral is clear of that little story is clear: astronomers need to keep the public on their side!

Now it’s time to start the workshop for today so I’d best be off…

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