Real Science

Monday, 19 February 2007

Intelligent design and the Loch Ness Monster


String theory is a leading candidate for a "theory of everything", but there is not a scrap of experimental evidence to support it and no obvious way of getting any, either now or in the foreseeable future.

The whole awe-inspiring edifice has got "caught up in its own mathematical beauty", according to an article in the latest Physics World. "Like Narcissus, it increasingly began to contemplate its own reflection, to the exclusion of observable phenomena," writes Michael Riordan in his review of physicist Lee Smolin’s new book.

Some string scientists have even begun to justify their evidence-free efforts, Riordan adds, by offering a new philosophy of science "in which hypotheses no longer require observable evidence in order to be accepted as valid theories."

To a hardened experimentalist like himself, he says, "this is blasphemy".

It’s an unfortunate choice of word, since it seems to concede the relativist position that science is no better than any other story we tell ourselves, or read in ancient texts, while trying to make exactly the opposite point - that unlike other belief-systems science is firmly based on solid evidence.

What's more, it is not only experimentalists who would reject this new philosophy of science: You’d have a hard job finding anyone in science research or education who would agree with it – or disagree with Riordan’s telling comparison with another piece of non-science:

"If we accept string theory as valid while it evades observational tests, how can we legitimately rebut arguments about the ‘intelligent design’ of the universe? The honest answer is that we cannot. For these arguments too are not falsifiable; they do not allow testing by measurements."

And yet and yet… What is and isn’t science is not always clear-cut. The scientific method police can get a little too keen.

Scientists from Texas A&M and UC at Berkeley have just set up a "high-tech sentinel" in the Arkansas bayou, to hunt for the ivory-billed woodpecker. The bird was believed to be extinct, but recent alleged sightings suggest reports of its demise have been greatly exaggerated.

But the evidence – a few audio recordings and some disputed photographs – is inconclusive. So the scientists have designed an intelligent video camera and image filter, which they are prepared to leave searching the woods for the elusive woodpecker for years and years and years.

Is that science?

Well patient search by people who call themselves scientists is a common activity, whether the objects sought are woodpeckers, gravitational waves, Higgs bosons or the Loch Ness Monster. But it’s not an activity that fits easily into the scientific method slot.

The scientific method was best described by Richard Feynman in a 1960s lecture to a classful of awestruck students: "In general we look for a new law by the following process. First we guess it. Then we compute the consequences of the guess to see what, if this law we’ve guessed is right, that this would imply.

"Then we compare the computation results to nature ... compare it directly with observation to see if it works. If it disagrees with experiment it’s wrong. In that simple statement is the key to science.

"It doesn’t make any difference how beautiful your guess is. It doesn’t make any difference how smart you are, who made the guess, or what his name is – if it disagrees with experiment it’s wrong. That’s all there is to it."

What the woodpecker watchers are doing bears very little resemblance to that model. Their theory that the ivory-billed woodpecker survives somewhere in the bayou is not falsifiable. No real-world test could prove it wrong. So are their efforts not science?

It is not an accusation that has, as far as I know, been made against the woodpecker hunters. But it was levelled rather strongly against SETI, the search for extraterrestrial intelligence, whose scientists have been conducting an almost identical activity for decades. (Except of course that they’re not looking for woodpeckers in space.)

"I take the hard view that science involves the creation of testable hypotheses," Michael Crichton said. "The Drake equation cannot be tested and therefore SETI is not science. SETI is unquestionably a religion."

SETI pioneer Frank Drake dismissed the criticism robustly: "There is no way by our search that we can prove there are not intelligent creatures in space. Even if we made the most extensive possible radio search and found nothing, perhaps there are civilisations out there which don’t transmit radio.

"So we cannot prove the negative. And some people say that means SETI is not science. Well, I think that’s just playing games with words. If you want to say SETI is exploration, fine."

I agree with Drake* And not just because Crichton, as well as being a best-selling author (Jurassic Park etc.), is also one of the Bush administration’s climate-change deniers - and I wouldn't believe that gang if they told me the day after Monday was Tuesday.

But all this does leave you wondering exactly what is science and what isn’t. And who decides.

If we insist on the scientific method, that consigns intelligent design and string theory to the fairy-stories file, but it also takes out SETI and the woodpecker watchers, among a host of other honest endeavours.

If we relax the criterion too much, we open the door to the cargo cults, a supernatural designer with an unexplained fondness for hairless monkeys, and far more parallel universes than there are elementary particles in the one we are just beginning to know.

Going back to my previous post, it is easy to figure out what art is. Art is what artists do and call - or sometimes don't call - art.

So is science whatever scientists do and call science?


Quick quiz. Which are science?
a) Ivory-billed woodpecker watch
b) Search for extraterrestrial intelligence (SETI)
c) Hunt for the Loch Ness Monster
d) Human-induced climate change
e) String theory
f) Intelligent design

(I go with yes, yes, yes, yes, maybe and no.)

* I’d like to share a few more words from Frank Drake, not because they shed light on what is science and what isn't - but just because they’re great words:

"I often think, as we’re observing and these little blips appear on the screen, that we are very much like people in the forest somewhere, with the wind blowing and the leaves rustling. Perhaps we hear in the distance human shouting, for a brief moment. But we can’t be sure.

"It could well be that that’s exactly what’s happening in our galaxy."

Saturday, 17 February 2007

Art of science


Daniel Holz, one of the guys at Cosmic Variance, raises interesting questions about art and science, arising from a talk he attended by Felice Frankel, a photographer who produces stunning scientific images.

He was surprised and disappointed, he says, by her insistence that she is not an artist and her photos are not to be considered art. He quotes her as saying: "This is why I am not an artist: I am deeply committed to maintaining the integrity of the science."

I agree that this is disappointing, but perhaps for different reasons. Holz thinks Frankel believes that being constrained to "reproduce the world as it is" means it can't be art. He disagrees with this, and cites the sonnet as a form in which rigid rules and high art work well together.

But as a photographic artist – whether she likes the word or not – Frankel is no doubt well aware that constraints are often conducive to creativity. Her vigorous rejection of artistic intent has, I am sure, other origins.

She is clearly anxious that her work will be criticised – almost certainly has been criticised - on the grounds that it is so accessible and aesthetically pleasing that it must misrepresent the science. This is precisely the same fear that prevented reputable scientists until recently from trying to explain their science clearly and appealingly to interested non-scientists.

Until people like Richard Dawkins and Paul Davies showed that attractive prose and scientific rigour were not mutually exclusive, a scientist who stooped to writing anything but the turgid stuff that fills the learned journals was committing a rather rapid form of professional suicide.

This is gradually changing, but disdain for the populariser still lingers in the loftier realms of academe, and far too few scientists are yet willing to write about their work for anyone other than their scientific peers.

Elegant and attractive prose does not have to distort science. And neither do beautiful, artistic images.

(The one at the top, incidentally, is by my son. He is an artist.)

Tuesday, 13 February 2007

DARTs in science

DARTs are directed activities related to text – and kids love them.

That's because they get actively involved with a piece of writing, instead of more or less passively trying to absorb and understand it. The kids ask questions of a text. They play around with it. They get to know how it works and what it’s all about.

In the process their understanding grows and so does their feeling of familiarity and sense of ease, with both the writing and its subject matter.

So what has all this to do with science? Not much at the moment, because although DARTs are being used to excellent effect in language and social studies classes, very few science teachers are yet using DARTs in their lessons.

But science teachers are being asked to reach out to youngsters who are disaffected and uninspired by the subject. And DARTs are one way of doing so.

At least they are if one other quality that school science lacks, in too many youngsters’ eyes, is added – topicality and relevance. OK make that two other qualities.

This is why DARTs are at the heart of the activities at www.realscience.org.uk

A particularly instructive kind of DART is the analysis of statement types – Activity 4. This explores the actual science in a story, and is often very revealing.

Take a look for instance at the story posted on 18 Jan 2007, which is at http://www.realscience.org.uk/sea3.doc (for UK readers) and http://www.realscience.org.uk/seaus3.doc (US). It’s all about what makes the seaside smell like the seaside.

Like the other stories that appear in realscience, this was written originally by a press officer.

We usually then have to do a fair bit of work to make a story readable to schoolkids. But this particular piece needed very little done to it. It already scored high on readability. It also achieved the most important aim of any press release: It jumped out from the dozens of stories that flit through a journalist’s inbox every day.

But the Activity 4 analysis shows that the majority of statements in the story are about existing, accepted knowledge, and not about the new research at all. The writer of the press release is good at her job, but she is clearly not a scientist. Very few press officers, or indeed journalists, are.

That’s one reason it’s so difficult to learn science from the newspapers.

Saturday, 3 February 2007

Talk like a scientist

They really should try harder. At a time when our political leaders are highly articulate but intellectually dishonest, and maybe even corrupt, scientists should be telling us clearly how things really are.

You didn’t need to be a rocket scientist to know Iraq had only short-range aerial transport for its weapons. You didn’t need a degree in nuclear physics to know those weapons couldn’t possibly include a fission bomb. You did need a little scientific knowledge – the difference between natural and enriched uranium, for instance – and a willingness to read the weapons inspectors’ reports.

Scientists should be speaking out clearly about such important issues. But scientists nowadays still communicate as they’ve always done – like it’s everybody else’s job to figure out what on Earth they’re talking about.

Take antibiotic resistance - the ability of modern bacteria to resist the wonder drugs that once destroyed them. Here’s what Steven Hagens said recently about his fascinating work (scroll down to Friendly killers) on using viruses to make antibiotics more effective, and maybe beat the bugs:

“Pseudomonas bacteria for example are particularly multi-resistant to antibiotics because they have efflux pump mechanisms that enable them to throw out antibiotics. A pore in the cell wall would obviously cancel the efflux effect.”

This, mind you, wasn’t in his original paper (published in Microbial Drug Resistance., 2006, 12 (3), 164). In that he says things like: “Noninfected PAO1 was resistant t0 1,500 mg/ml of carbenicillin, whereas a concentration of 200mg/ml carbenicillin was sufficient to inhibit growth in the presence of the Pf3 phage.”

But that’s fine. That’s how scientists write when they’re writing for scientists. Precision takes precedence over elegance.

No, that stuff about pores cancelling efflux effects was in an interview with a trade paper aimed at chemists and businessmen – none of whom, I suggest, would have found it in the least bit obvious. The words were then taken up and circulated by a press officer to science journalists.

Since journalists need quotes, that one would have been picked up and used verbatim by many of them, leaving even their best-educated readers wondering why – if this was so obvious – they couldn’t make any sense of it at all. So next time a science story appears in their newspaper what will they do?

Chances are they’ll skip to something they know will make sense and won’t make them feel dumb - such as the latest piece of inane emptiness and distorted reality from our political leaders.

The story is told of the eminent mathematician G H Hardy that he was once giving a lecture when he made a casual remark, and said, “Of course that’s obvious.” Then he stopped talking and looked very thoughtful. Time wore on and he continued staring dreamily into space. After a while the class was getting very restless, but finally the great man emerged from his deep thoughts and said to the students:

“Yes I was right – it is obvious.”

Now that sort of thing makes sense to a mathematician or a scientist, but not to normal people. So come on guys. We want you to explain things to us. We need you to explain things to us. But don’t come out with some piece of gobbledygook, tell us it’s obvious and make us feel like morons.

Try to talk English for heaven’s sake. It's our future that's at stake.

BACK to the story at realscience.org.uk

It's a breeze


Despite having been a scientist most of my life - one of my earliest memories is of being told not to ask so many questions - I'm still amazed by how much information can be wrung from the natural world.

Astronomers from the University of Washington have just figured out that three planets around distant stars have winds blowing on them up to 9000 miles an hour. Now that's big winds. My garden fence blew down last night in a January storm that reached 70 miles an hour. They must build their fences strong on 51 Pegasi's planet.

Of course there are no people there, or on the planets orbiting HD179949b or HD209458b, the other two star systems studied. These are gas giants like Jupiter, only much closer to their parent suns. So they’re hot – about 925 degrees Celsius at their surfaces – and their atmospheres are pretty poisonous.

Anyway the point is that just discovering these planets is a major achievement. No telescope on Earth can see them. The closest is 50 light years away – that’s 294 million million miles. Even the Hubble Space Telescope can’t see them.

So how do they know they’re there? The most common technique uses the fact that the gravity of the planet pulls its sun slightly out of position. Planet and sun waltz around each in a gravitational dance. But because the sun is so much more massive than the planet, it moves much less.

All the same, this movement can be detected because it affects the colour of the light that reaches us from that sun. From the regular cycles in this light you can work out the mass of the planet, its distance from its sun, and how long it takes to complete one orbit (the length of its year).

That’s a lot of information from a pinpoint of light. But there’s more. The gravity of an object causes tidal forces on a nearby object, just like the tides we have on Earth. These tidal forces slow down a planet’s rotation, and over a long time stop it completely. The closer the two bodies the sooner this happens.

The sums show that all these planets have stopped spinning, so their days last forever and so do their nights. The day side facing the sun should be as hot as Hell, while the night side should be colder than an Aberdeen winter.

But they don’t seem to be. How do we know? Well all that information about the planet’s orbit around its sun tells us when the day side is facing Earth across the depths of interstellar space, and when the night side is facing Earth.

Now hot objects emit copious quantities of infrared radiation, cold objects much less. So if you study these systems with infrared telescopes – these scientists used the Spitzer Space Telescope – you can work out the temperature. That’s where the 925 degrees Celsius for the surface temperature of the planets comes from.

But the really surprising part is that the astronomers could detect no difference in temperatures between the night and day sides of these planets – despite the fact that one has no source of direct heat while the other’s sky is filled by a blazing sun.

So the heat must be getting from the day side to the night side – carried by winds so strong that my garden fence would be knocked down, blown away and blasted into its constituent molecules.

As I said, what science can do with a sprinkling of data and a dash of knowledge constantly amazes me.

BACK to the story at realscience.org.uk (Scroll down to: It's a breeze)