Pluto in context : the big eighty eight

March 30, 2007

Check this out : a web developer in Boston has made a stunning image of all eighty eight objects in the Solar System bigger than 200 miles across. (Miles ??!!??? Well, I guess that’s America for you …) . Pluto is number eighteen.

So .. wanna pick out a handful and give them a special name ? How about eardstapa ? (Anglo-Saxon for Wanderer). Maybe some of us will pick eight eardstapas and some will pick nine, and we can have jolly interesting reasons for why something ought to be an eardstapa, or not. The nine-eardstapa camp can start an internet petition, and the eight-eardstapa people can get a motion passed at an Assembly of Very Important People.

Planet is a word, people. Take a look at the Universe.

Quantum Mysticism : not as good as Pooh

March 28, 2007

I am trying to get to grips with David Bohm and failing utterly, as much through boredom as stupidity..

The low-l anomaly in the cosmic microwave background, discussed by Andrew Jaffe in his seminar here last week, gets people excited because it hints at a violation of causality. Long distance quantum entanglement excites people for much the same reason. You spit out a pair of particles that must have opposite spins, but the spin of either one is not determined until it is measured. So then you measure one, and instantaneously force the other, distant, particle to have a specific spin. The laws of physics, some say, are in a deep sense non-local. Everything is connected. Err…

If you google “everything is connected” you mostly get lots of wishy washy mysticism, with the odd bit of quantum mechanics thrown in. Well, as you will see from some of my posts, while I am vaguely antagonistic to Western religions, I find Eastern mysticism very interesting, while trying to stay healthily sceptical. This sort of interest is of course quite normal for someone of my age whose hair used to be much longer and who still has some pink loon pants somewhere in the attic, and who occasionally plays his crackly Steve Hillage albums on his Rega Planar. (Now we’re all reality gypsies).

So there I was in the bookshop and found myself picking up “Wholeness and the Implicate Order” by David Bohm. The blurb says he is not only famous for his hidden variables interpretation of quantum mechanics, but was inspired by Eastern Philosophy, and blended the two to arrive at a new way of looking at the Universe, including consciousness. Wow. Can’t wait.

A week later I have managed a few dozen turgid pages per night. The bits of physics in it do look really interesting, but I’d have to read the real papers to be sure, and my brain hurts already. But the philosophy seems to be vapid gibberish. Its full of pointless neologisms, repetition, obscure phrasing, and a kind of Vedic philosophy muddled and watered down to a sort of murky soup.

I’d hate to think anybody would think this is what Eastern philosophy is really like. Better to go straight to the Tao Te Ching. Or possibly even better, the Tao of Pooh.

Or maybe just read The House at Pooh Corner. Alternated with chapters from the Feynman Lectures.

Telephone sanitation and the Cosmic Microwave Background

March 24, 2007

On Thursday Andrew Jaffe from Imperial College was up giving us an excellent seminar on the CMB, and what the strange low-l anomaly could mean. Andrew has an excellent blog called Leaves on the Line, from which I learned that just before he came up from London he cleverly locked himself inside his own house. So for more reason than one we were pleased to see him.

In the pub afterwards, when there was a temporary pause in the arguments about Bayesian statistics versus frequentism, John Peacock mentioned that the other day he noticed his ear was sticky after using his phone. Apparently our cleaners spray some sort of gharrsly disinfectant on them every so often. So I guess they are telephone sanitation operatives, and Douglas Adams knew more than we realised. Maybe deep inside Cheyenne Mountain they are secretly building the B-ark as I write …

So I googled “telephone santitation” and entry number one was United States Patent 4819264 for a telephone sanitation device involving a disinfected foam pad. Damn. Why didn’t I think of that.

Screw Pluto Lets Bring Back Ceres

March 21, 2007

Edinburgh Students are just catching up with New Mexico Legislators…HST picture of Ceres as noted by the Bad Astronomer, the State of New Mexico recently passed legislation declaring that Pluto is a planet, at least while passing through New Mexican skies. The State of California has debated an even more amusing bill. If we are not careful the IAU will get billed by California State Schools and Museums for the cost of changing educational materials. One detects a certain knowingness here. This burning issue has now been spotted by our local student newspaper, who noted that Plutan Officials have so far not reciprocated by recognising the legitimacy of the State of New Mexico.

Pluto expert I is not, but I was at the infamous IAU vote in Prague, and wrote a post about it. This got discovered by Laurel Kornfeld, who spearheads the “Please Save Pluto” petition, and somehow we ended up having a debate on somebody else’s blog. I checked out the petition. The quality of the comments on the signatures page puts that shabby and hurried IAU debate to shame, of course. I tried to Vote but couldn’t make it work. Hmmm.

New Mexico feels a special connection because Clyde Tombaugh, discover of Pluto lived there. Maybe I can get the Scottish Executive to vote to bring back Ceres ? Ceres of course was called a planet for about fifty years until the list of similar size things between Mars and Jupiter made this a bit silly and it got demoted. Sound familiar?

Lets cook up some connections. I am the Regius Professor of Astronomy, and my predecessor was Charles Piazzi Smyth, whose godfather was Giuseppe Piazzi, who disovered Ceres in Palermo in 1801. My good friend Pepi Fabbiano Pepi Fabbianocomes from Palermo. (Well, ok, she lives in Cambridge now..) Best of all, just up the road in the Kingdom of Fife, is the town of Ceres. We can start a petition, hold an international conference in Ceres, and convince the Scottish Executive that the Honour of Alba is at stake, noting that exchange visits to Sicily would be rather jolly.

The Dawn mission, launching this year, is due to visit Ceres and will get there BEFORE New Horizons reaches Pluto ! Controversy and Competition – even better ! The time is now ! This sounds like a real winner.

If I can be bothered.

The real reason why global warming doesn’t matter

March 14, 2007

Because energy disaster looms anyway. Pretty soon, one of three things will happen : one, we achieve a sustainable low energy culture; two, we solve all the worries of nuclear power and have a high energy lifestyle; or three, civilisation collapses and we revert to a mediaeval economy.

I watched the Channel 4 documentary “The Great Global Warming Swindle” and have been trawling the blogosphere for comment since. Reactions divide pretty evenly in two. One half is along the lines of “Completely convincing ! I always suspected global warming was a hoax and now its been proved !” and the other half, who say “Sigh. Where do I start explaining the mistakes ? And these guys are all marxists with a weird agenda anyway.” As a piece of agit-prop, it was superb. Beautifully made, clearly argued, with just enough emotion to engage you, but not so much you get suspicious. Although there were one or two semi-cranks interviewed, there was also an impressive list of real scientists. However, at least one of those has now complained that his views were misrepresented…

As an astronomer, the argument that the dominant factor in climate change is cloud cover variation caused by changes in solar cosmic ray flux is of course appealing. (There is a useful explanation here, and some informed criticism here) There is a small chance that this completely explains climate change, but mostly it just adds a systematic uncertainty, making it harder to estimate the correct magnitude of anthropogenic climate change. The C4 show mocked the “precautionary principle” but its correct; given how long the world economy supertanker takes to turn around, can we take the risk that its all an illusion ?

So now the scary bit. As the oil runs out, we may end up with catastrophically less energy consumption, and correspondingly less carbon production, and so avoid global warming and just have darkness, poverty, and misery instead.

So… when the question of when the hydrocarbon reserves will run out is another famously contentious issue of course. I am not a technical expert, but I did read an excellent popular book – “The End of Oil” by Paul Roberts. Coal may last somewhat longer, but it has to go eventually, and meanwhile we keep getting greedier …Roberts does a nice analysis of growing energy needs. With our current rate of energy consumption growth and population growth, and assuming that developing nations catch up with the West, but also allowing for continuing improvements in energy efficiency, Roberts estimates that by the year 2100 the world energy consumption will be 50 TW. (50 TeraWatts, or 50 times a million million Watts).

Decades before this the oil and coal will be running out or becoming unproductive to extract; and many years before this the increasingly difficulty of extraction will be leading to horrible international tensions.. this is starting now of course. So new energy sources must come to our rescue !! Biofuels, hydrogen, wave power, solar energy, wind farms .. the more the better !

But what Roberts, and most others, don’t point out is that there is a renewable bottom line : the solar constant. All renewables are driven by solar energy – plants are recycled sunlight, the wind is driven by solar heating, and so on. Hydrogen cells are just a storage mechanism. Something has to make the energy first. Hydrocarbons of course represent millions of years of accumulated sunlight stored up underground. Once they are used up, we can’t use more energy than is falling on the surface of the Earth. There are only two exceptions. The first is nuclear power. The second is geothermal energy. However the heat emerging from the entire land surface of the Earth is somewhat less than the current world energy consumption, so this will never be a big factor.

So how much sunlight is there ?

The total amount of solar radiation falling on the surface of the earth is roughly 1.7 x 10**17 Watts. Thats everything – all wavelengths, falling on the oceans, Antarctica, or whatever. How much can we use ? Half of this is reflected. We could maybe at most cover 1% of the Earth with photo-cells with 10% efficiency, or perhaps 10% with biofuel crops at 1% efficiency. All in all, in round terms we might get half of one thousandth of the above if we are lucky. Thats 85 TW max.

The astute reader will now notice that this (85 TW) is close to the predicted world energy consumption in 2100 (50 TW). A somewhat bigger growth, or a somewhat less optimistic return on solar energy, and we simply won’t make it. We are perilously close to a magical dividing line in human history. There are three paths from here :

(1) We solve the problems of nuclear power and get as much as we want.

(2) We build a global lifestyle that stabilises at 5kW each.

(3) We do nothing until war and chaos destroy the global infrastructure and we revert to a mediaeval economy.

Even scarier, uranium supplies are finite so nuclear fission may be no good either. (Understandably, this is vigorously denied by the Uranium Information Centre of Australia ..) So how about fusion ? Well its promising but we have been trying for decades and still can’t get out more energy than we put in, let alone produce energy on an industrial scale.

Maybe I should teach my kids how to use a bow and arrow, and move to the Hebrides.

Moondance in Muenchen

March 12, 2007

Six a.m. in a German hotel room and I am rescued by Van the Man. I have woken up annoyingly early, worries about e-science politics and the talk I have to give this morning buzzing in my head. I put on my earphones and listen to “Moondance” by Van Morrison, hoping to fall back asleep. Music can switch your head into a different mode. This works but I haven’t fallen asleep : instead as I listen to “It Stoned Me” I am awake and happy. It stoned me too. And I didn’t even need to get wet. (Check it out). Thank you Van.

This is a strange but cool hotel. The rooms don’t have numbers. They are all named after famous artists. I am in “Max Ernst” and my colleague Kona Andrews is in “Joan Miro”. It reminds me of the opening chapter of “Gravitation” by Misner, Thorne, and Wheeler. (How pretentious is that ?) This is about how you don’t have to be chained to co-ordinate systems, and instead think in terms of geometric objects. They explain that in Japanese towns streets don’t have names, and houses within blocks are numbered not in order of position, , but in the order they were built. (You can find an explanation here.) Yet somehow the postman has no trouble delivering letters.

This always seemed simultaneously deep but irritating. Does it really work in practice – the Japanese postman in a big town, or real GR calculations ? There are about three floors and twenty-ish rooms here so nobody gets lost I guess. But if Best Western tried the same thing, this would be impossible … wouldn’t it ?

Anyhoo. Nice hotel, in a good spot in central Munich, so here is a plug. Its Hotel Occam, in Occamstrasse, near the Englischer Garten. It has no wireless internet, so I will put up this post later, when I get to ESO.

Red Moon in the trees

March 3, 2007

The lunar eclipse is under way .. its so beautiful. I can’t believe the sky is clear in Edinburgh. Through my binoculars, it looks much more three dimensional than normal, grading from blood red through to ashen blue. From my tiny city garden, we see it through the branches of a tree, while chatting students emerging from the pub drift past the garden wall, oblivious.

Waking Up on the Cosmic Express

March 3, 2007

Roaming round the science blogs these days, every third post seems to be about Science Versus Religion – for example here, and here, and even one from me. One of the best was “Thank You Richard Dawkins” over at Cosmic Variance, which provoked a long and strange debate. I find this phenomenon both invigorating and alarming, as my fellow scientists are basically right but often oddly strident. I have found myself repeatedly daydreaming about a striking conversation that took place a year or so ago on my way to an observing run at the UK Infrared Telescope (UKIRT).

What follows is essentially as it happened, but fictionalised for heuristic effect. If Veet reads this, he will understand.

I am flying from London to LA, en route to Hawaii – the Cosmic Express, the UK Astronomy Special. I have just had an idea and am scribbling some calculations on my newspaper. The man in the next seat asks me what I am doing. I explain that I am a scientist, and go on to say that I am on the way to use a new wide field camera on a telescope on top of the Big Island. Fascinated, he gently grills me. His questions are very cogent, initially naive but rapidly sharpening as he listens to my answers. I begin to wonder if he is teasing me and is actually a Dutch astronomer – but no, he is just intelligent and well read, with the kind of intellectual freedom that goes with lack of responsibility – he is called Veet and he scratches a living on Kauai tutoring the children of wealthy farmers.

I go on to explain how the infrared is important because you can see cold things, things hidden by dust, and very distant, redshifted things. He swallows all this with a pleased grin. Then somehow, at a pause, religion comes up – I don’t remember how. He says that the problem with the world is that our science and technology is very advanced, whereas our religion is still primitive. What we need is more advanced religion.

I snort. Advanced religion, I say, would be advancing it to the point where you have no religion. Religion is like a bad dream that humanity has woken from now that we understand nature, and have material comfort and democratic social structures. Fairytales are not needed – we are not frightened, or puzzled, or oppressed. God is unnecessary.

So who mentioned God ? says Veet. It soon becomes clear that he finds the Abrahamic religions more absurd and worrying than I do, seeing them as a kind of virus, a slave system that traps people, and enemies of knowledge and truth. I find myself defending Islam and its role in preserving science through the dark ages, but he downplays this, saying that the scholarship was always carried out by subject peoples conquered by Islam.

But, he says, this doesn’t mean there is no spiritual aspect to life, and in fact the scientific approach, a healthy scepticism, leads us in a consistent direction. There is no personal self; it is an illusion caused by memory, the continuity of physical structures neighbouring in space. The point is to arrive at this insight before the illusion vanishes at death. Suffering arises from grasping; when you know you do not exist, suffering ceases. Ah, I gradually realise, this is Buddhism. So … how about this re-incarnation mumbo-jumbo ? If there is no self, what is the thing that pops back in to another body ? He smiles. Yes, Buddhism is more advanced than gods-in-the-sky, but perhaps not yet the final story. His point exactly.

The self, he suggests, is like a waterfall. It looks like an object, but its really a process. Its caused by the landscape, making the water flow in a structured way .. for a while. The waterfall isn’t real. Only the water is real. OK, say I. This is like Heraclitus – a man can never step in the same river twice. Uhuh, says Veet. Its not the same river, and its not the same man. Nice game, I say … but whats the water here ? He smiles. Just because there is no personal self doesn’t mean that there is no consciousness. It is obvious that consciousness exists in the Universe, along with matter, and energy. But it must be a single universal field, which follows the landscape and produces temporary structures. Somehow as organisms we participate temporarily in this universal field of selfness. Mystics have been saying the same thing for thousands of years.

Now I get cynical again. We are heading down Mysticism Road towards Gibberish City. All is One. You too are Brahman. The world is a Veil of Illusion. You may think you see the real world, but you don’t. The reality is something stranger, deeper, mistier, which only the Master can really see. This stuff is very clever, but just another delusional fantasy. Like String Theory ? he asks with a grin. Well, yes, I say. The point about science is that you may have elaborate explanations, but you keep it concrete, you stay grounded in experience. You are sceptical, and you test your ideas against Nature. If it disagrees with experiment, its wrong. Doesn’t matter whether a Grad Student said it or Ed Witten said it. If Nature says no, it isn’t so. On this basis, Quantum Mechanics may be weird, but its solid. String Theory isn’t even right or wrong yet. Its a beautiful idea waiting to become science one day. And as for merging with Brahman.. well where do you start ?

Long Pause. He holds up his pen. What’s this ? he says. Its a pen, I say. No, he says, “pen” is a noise. This is what this is. He hands me the pen in silence. I just stare at it for a while. I can see a tiny glare of light reflecting off a tangent. Its blue at one end and green-ish at the other. The pen is light, but I can feel its weight, and I roll the pen on my palm. Its smooth but I feel a slight tickle on my skin.

The point ? I can put this in scientist-talk, he says. In our heads we have a model of the world. Words, concepts, equations. Powerful but confusing. The illusion is that we mistake this buzzing mental world for the real thing. So you see mysticism is the opposite of your caricature, and quite like your empirical worldview. The illusory world is complex, confusing, fuzzy, and only Ed Witten can really understand it. But let this drop away and the real world is concrete, definite, hard, bright and simple. Its exactly the same as before but without the crap.

Interesting. Reminds me of the philosophical debates from the early days of quantum theory about whether the theory represents something real, or is just a convenient instrument; a machinery for calculating what happens in Nature. It works, but maybe there could be other instruments that would do just as well. Just because it works doesn’t mean it reflects some underlying essential reality. Well, I guess philosophers still make a living going round this circle. But working scientists see that debate as a failure of nerve. Electrons and quarks are real. We make concrete progress and understand the world better each day. This is not a game. There is a knowable reality.

Woah, says Veet. Thats a pretty strong theological position ! The scientific credo. I thought you guys were thorough-going sceptics ? To me, he says, scientific theories are not discovered, they are created. They are as beautiful as Hamlet or Beethoven’s Ninth. They are a great human achievement.

I wriggle, having been trapped into seeming dogmatic. Yes, ok, I say, if you work only on theory, you can never be sure you are not fooling yourself. Grounding in the concrete observed world is crucial. And in science, you always have to be ready to say you were wrong, and then your theory goes out of the window. But, look, the point is, science works. Airplanes fly. Transistors get invented. Its not a beautiful but arbitrary fiction. Our scientific creations are somehow connected with the real world, and they are useful.

Same with Hamlet, says Veet.

Long pause. I rattle the ice in my coke. The plastic cup is so thin I can feel the ice bump against my fingers. I can hear the people behind us talking and laughing. Guess I tuned it out before. I turn back to Veet.

Well, its interesting to hear mysticism isn’t what I thought. Don’t get trapped by the words, keep connected to the physical world. Thats cool. But then, so what ? This doesn’t seem deep. Clear some clutter from your mind and its kinda obvious.

Exactly, says Veet.

The sun is coming through the window. The light of day is like a block of glass. Everything is the same as before.

UKIDSS marches on

March 2, 2007

Yesterday saw the second data release (DR2) of the UKIRT Infrared Deep Sky Survey (UKIDSS), the biggest infrared sky survey so far. The UKIDSS home page is here, but you get the data from the WFCAM Science Archive (WSA).

I am the PI of the survey, but lots of other people do more work than me – especially Survey Scientist Steve Warren, who is the lynchpin of the whole thing, and Nigel Hambly, who masterminds the WSA. Nige is the one who has been losing sleep getting ready for the release..

This event put me in mind of a strange day a year back when I went out to Hawaii to do a UKIDSS observing run, and got stuck into a five hour conversation about science and religion. I would have expected this to irk me, but in fact it was fascinating .. I will try to write this up over the weekend…