Archive for the 'Science' Category

The sociology of cosmology

Published
by
peter
on 2011-11-04
in Science
. Closed

Physicist Per Bak:

“I once raised this issue among a group of cosmologists at a high table dinner at the Churchill College at Cambridge. “Why is that you guys are so conservative in your views, in the face of the almost complete lack of understanding of what is going on in your field?” I asked. The answer was as simple as it was surprising. “If we don’t accept some common picture of the universe, however unsupported by facts, there would be nothing to bind us together as a scientific community. Since it is unlikely that any picture that we use will be falsified in our lifetime, one theory is as good as any other.” The explanation was social, not scientific.” (Bak, page 86)

Reference:

Per Bak [1999]: How Nature Works: The Science of Self-Organized Criticality. (New York, USA: Copernicus)




Resilient capitalism

Published
by
peter
on 2011-10-20
in Computer technology, Design, Forecasting and Science
. Closed

Yesterday began with a meeting at an investment bank in Paternoster Square, London, which turned out to be inaccessible to visitors and the public.   The owners of the Square had asked the police to close public access to prevent its occupation by the anti-capitalism (OWS) protesters, encamped between the Square and St Paul’s Cathedral.  So our meeting took place in a cafe beside the square.

The day ended with a debate at the Royal Society, organized by The Foundation for Science and Technology, on developing adaptation policy in response to climate change.     The speakers were Dr Rupert Lewis of DEFRA, Sir Graham Wynne of the Sub-Committee on Adaptation, UK Committee on Climate Change, and Tom Bolt, Director of Performance Management at LLoyd’s of London.  (Their presentations will eventually be posted here.) As Bolt remarked, insurance companies have to imagine potential global futures in which climate change has wrecked social and economic havoc, and so are major consumers of scientific prognoses.   One commentator from the audience suggested that insurers, particularly, may have a vested short-term financial interest in us all being pessimistic about the long term future, although this inference was not obvious to me:  one human reaction to a belief in a certainly-ruinous future is not to save or insure for it, but rather to spend today.

A very interesting issue raised by some audience members is just how do we engineer and build infrastructure for adaptability?  What would a well-adapted society look like?     One imagines that the floating houses built in the Netherlands to survive floods would fit any such description.  Computer scientists have some experience in creating and managing robust, designing resilient and adaptive systems, and so it may be useful to examine that experience for lessons for design and engineering efforts for other infrastructure.




Evolutionary psychology

Published
by
peter
on 2011-09-27
in Hands, Human intelligence, Music and Science
. Closed

In his Little Red Book, Mao Tse Tung said:   “Learn to play the piano.”  However,  I don’t recall ever seeing a single piano in an African village, although I certainly saw (and heard) piano accordians in the villages and along the mountain paths of Lesotho (along with various hand-drums and mamokhorongs).  And settlements larger than traditional villages – Zimbabwe’s Growth Points, for example – sometimes had pianos in their churches or newly-built school halls.  Of course, the earliest of these pianos could only have been made in these last 300 years.

It seems to me that the historical absence of village pianos in Africa causes a problem for evolutionary psychology, since clearly a daily compulsion to play the piano is not something that has a long-standing evolutionary basis – at least, not for those of us descended from the peoples of the African savannah.  So if evo-psych cannot explain this very real human characteristic, what business does it have explaining any other human characteristic?  Why are some attitudes or characteristics to be explained by evolutionary means yet not others?  What distinguishes the one class of characteristics from the other? And what credence can we possibly give to any evolutionary explanation of phenomena which is not, prima facie, explainable in this way?   Surely, this limitation of the scope of evolutionary explanations completely undermines such arguments, since either all higher-level human characteristics have evolutionary explanations or none at all do.




Reliable Knowledge

Published
by
peter
on 2011-05-28
in Getting-things-done intelligence, Mathematics, Religion and Science
. Closed

How little scientists know who only know science!  Thanks again to Norm, I learn about some statements by a retired professor of chemistry, Peter Atkins, about how we know what we know.   Atkins is quoted as saying:

The scientific method is the only reliable method of achieving knowledge.”

Well, first, it is worth saying that the scientific method does not produce reliable knowledge.  One of the two defining features of science is that scientific claims are defeasible:  they may be contested, questioned, challenged, and even overthrown, if the evidence warrants.   There is nothing inherently reliable about any scientific claim or theory, since new evidence may be found at any time to overthrow it.  The history of science is littered with examples.   (The second key feature is that anyone may do this contesting; science is not, or rather should  not be, a priesthood.)

Continue reading ‘Reliable Knowledge’




Let Newton Be!

Published
by
peter
on 2011-04-20
in History, Matherati, Religion and Science
. Closed

Belately, I want to record a play seen at the headquarters of The Royal Society in London last month, Let Newton Be, written by Craig Baxter, but using only Isaac Newton’s own words.     The play was interesting although the energy of the play sagged at times, particularly in the first half.   The story only barely mentioned Newton’s interest in alchemy, and seemed to overlook his brutal, deadly campaigns against money forgers later in life (or did I nap through that scene?)

The play comprised three actors, two men and a woman, who played Newton at different ages – as a child, as a young-ish Cambridge academic, and as an old man.  As a work of drama, the conceit worked well, although it was best when one of the actors was playing another person interacting with Newton (eg, Halley, and later Leibniz, who spoke in an amusing cod-German accent).  Perhaps the real Newton was not sufficiently schizoid for three actors to play him, at least not when constrained to only use the man’s written words.    As I have remarked before, Newton’s personality was all of a piece:  it is only modern westerners who cannot imagine a religious motivation for activities such as scientific research, for example, or who find alchemy and calculus incoherent.

The performance was followed by a panel discussion by the Great and the Good – two historians and two scientists.  One of the scientists was the Astronomer Royal, Sir Martin Rees, who has subsequently won this year’s Templeton Prize for Science and Religion.  The discussion was interesting, so it is a pity it was not recorded for posterity.

A review of another play about a member of the matherati, Kurt Godel, is here.




Please post your apology here, Dr.

Published
by
peter
on 2010-11-26
in Medicine and Science
. Closed

I have mentioned before the long-standing medical trope of first blaming the victim of an illness before identifying  its real causes.      To cholera (blamed on loose morals), drug addictions (blamed on weakness of will), stomach ulcers (blamed on a personal inability to handle stress), chronic fatigue syndrome (blamed on laziness), and repetitive strain injury (blamed on deception, or even self-deception), we may soon be able to add obesity and schizophrenia.

The contemporary developed world obesity epidemic has always struck me as being too widespread and occurring too fast to be due simply to a lack of self-discipline by lots of individuals.   Current medical advice is for individuals to eat less and exercise more, advice given despite the experimental evidence showing that increasing exercise actually may increase weight (on average), rather than reducing it.    And advice given despite the fact – known for at least 150 years, since the work of Claude Bertrand – that our bodies are complex adaptive systems, whose properties do not conform to simple linear models; for example, eating less may lead the body to retain more of the nutrients of the food ingested, because of a body-weight set-point effect, and thus not lead to much weight loss at all.   We already have evidence that appetite may have  genetic determinants.  Now, it seems that the obesity epidemic may have environmental or social causes, since as well as humans in the developed world putting on weight, so too have animals.  The animal species studied include not only pets and zoo animals (whose diets may have been influenced directly by human feeding), but also wild animals living near humans.

And schizophrenia, which once was blamed on poor parenting by the mothers of patients, and later on the patient’s genes (and who, Mothers, gave them those?), may in fact be caused by a virus – a retrovirus, present in our and our ancestors’ DNA for some 60 million years.  It turns out this is the same retrovirus that is believed by some scientists to cause Multiple Sclerosis.  A virus as cause could explain why there is a persistent, and statistically significant, effect on the incidence of schizophrenia arising from the season of birth of the patient.  Neither genes nor a mother’s parenting style would be expected to be influenced by the season of birth, but virus lifecycles, activations, durations and diffusions, certainly are.

The standard line initially of the medical panjandrums on RSI was that this medical condition only seemed to affect office workers, and not others who worked a lot with their hands, such as musicians.    The implication of such a statement was that the causes of RSI could not be some objective condition, outside of the patient, and so must be internal, either psychosomatic or actually knowingly invented.  Yet, musicians for at least a couple of centuries have been suffering from RSI (or closely-related conditions), as anyone who asked them would know.

When the medical profession is ready to apologize to us all for wrongly accusing us of moral failings, weakness of will, or malfeasance, I’ll be here ready and waiting.  I’m not, however, holding my breath.




Dyson on string theory

Published
by
peter
on 2010-09-12
in Mathematics and Science
. Closed

Physicist and mathematician Freeman Dyson on string theory:

But when I am at home at the Institute for Advanced Study in Princeton, I am surrounded by string theorists, and I sometimes listen to their conversations. Occasionally I understand a little of what they are saying. Three things are clear.  First, what they are doing is first-rate mathematics. The leading pure mathematicians, people like Michael Atiyah and Isadore Singer, love it. It has opened up a whole new branch of mathematics, with new ideas and new problems. Most remarkably,  it gave the mathematicians new methods to solve old problems that were previously unsolvable.  Second, the string theorists think of themselves as physicists rather than mathematicians. They believe that their theory describes something real in the physical world. And third, there is not yet any proof that the theory is relevant to physics.  The  theory is not yet testable by experiment. The theory remains in a world of its own, detached from the rest of physics. String theorists make strenuous efforts to deduce consequences of the theory that might be testable in the real world, so far without success.

. . .

Finally, I give you my own guess for the future of string theory. My guess is probably wrong. I have no illusion that I can predict the future. I tell [page-break] you my guess, just to give you something to think about. I consider it unlikely that string theory will turn out to be either totally successful or totally useless. By totally successful I mean that it is a complete theory of physics, explaining all the details of particles and their interactions. By totally useless I mean that it remains a beautiful piece of pure mathematics. My guess is that string theory will end somewhere between complete success and failure. I guess that it will be like the theory of Lie groups, which Sophus Lie created in the nineteenth century as a mathematical framework for classical physics. So long as physics remained classical, Lie groups remained a failure. They were a solution looking for a problem. But then, fifty years later, the quantum revolution transformed physics, and Lie algebras found their proper place. They became the key to understanding the central role of symmetries in the quantum world. I expect that fifty or a hundred years from now another revolution in physics will happen, introducing new concepts of which we now have no inkling, and the new concepts will give string theory a new meaning. After that, string theory will suddenly find its proper place in the universe, making testable statements about the real world. I warn you that this guess about the future is probably wrong. It has the virtue of being falsifiable, which according to Karl Popper is the hallmark of a scientific statement. It may be demolished tomorrow by some discovery coming out of the Large Hadron Collider in Geneva.” (page 221-222)

Reference:

Freeman Dyson [2009]:  Birds and frogs.  Notices of the American Mathematical Society, 56 (2): 212-223, February 2009.   Available here.




The world beyond our five senses

Published
by
peter
on 2010-09-09
in Religion and Science
. Closed

Over at Normblog, Norm has a typically open-minded discussion about religion and its possible attractions for its adherents:

Both Howard [Jakobson] and Tim [Crane], then, neither of them speaking as a believer, sees religion as making the world, so to say, fuller for its adherents – with more of interest, of meaning, of things, even, beyond our grasp. This reminds me of the occasion I asked a religious friend about the basis of his belief and he cut the conversation short by saying simply that his life would be poorer without it.

All I can say is that this account of religion doesn’t work for me – I mean, to shift me – and for two reasons. The first is that the world seems like an intensely interesting place already, without any extra population of meanings and mysteries. Just look, read. There’s no end of it, never mind a fullness. The second is that I don’t feel free to add a further layer of things to those for which some evidence can be supplied, and if I did, I wouldn’t know where to stop. Why just those mysteries?

I think Norm, and the accounts he cites, miss something that is often important both to religious believers and to practitioners of religious activities (two overlapping but not identical groups, as I have explained before).    What is missing is that for many people in these two groups, their interest in religious ideas and practices arises from a contact they have had, or which they perceive they have had, with entities from a non-material realm. This contact usually involves none of their so-called five senses, but is experienced deeply nonetheless.  One can know something from merely being in the presence of somebody, as may happen, for example, when we experience the strong love of another person.

Of course, it may be that people who have had such spiritual experiences are deluded in thinking they had them, or even, that they delude themselves.  Experiments exciting certain parts of the brain with small electric currents can apparently induce very similar perceptions of religious experiences in people.   Even so, such experiments do not demonstrate, or even make likely, the absence of non-material entities; in precisely the same way, patients with tinnitus do not demonstrate that we all live in a silent universe.

So it is perfectly possible that people who perceive they have had direct contact with non-material realms may indeed have had such contact.  This possibility exists even though Richard Dawkins and many another famous person seem not to have had such experiences.  Moreover, the lack of spiritual experiences for some people also tells us nothing about the existence or non-existence of spiritual realms and beings.   Not all of us are born able to hear, for example, but the fact that some people are born deaf is also not usually taken as a sign that the universe itself is silent.  It may thus, indeed, be those who believe that they have not had contacts with a non-material realm who are deluded, or who are deluding themselves.  In a situation of such widespread ignorance, with neither replicable evidence for the existence of spiritual entities nor any evidence against their existence, it behooves no one to be arrogant about his or her position.  (For the record, I do not count Norm in this combined category of arrogant atheists and arrogant religious believers.)

And to Norm’s larger point:   If a person has had such an experience, what does she find?  First, she finds that the experience is entirely discounted by science, since it cannot be replicated via experiment.  This arrogant disdain for phenomena that it cannot yet explain has sadly been a feature of western science since its inception.   Second, she finds that she cannot talk openly about this experience, at least not in a modern western office or university.    In the supremely rationalist environment of our business and education worlds, talking about spiritual experiences among colleagues is one sure way nowadays to receive laughter, scorn and derision.   That is very different from, say, the situation in the West in the middle of the 19th century, or the situation still today in Africa or in Australian Aboriginal society, societies where spiritual experiences are widely respected.   Having lived in both the West and in Africa, I know this difference very well.   Third, she would find no explanation or meaning for her experience in any academic discipline, apart from theology and poetry, and perhaps the arts and music.    She would, however, likely find great sympathy from pure mathematicians, who grapple daily with entities which seem to have existence and properties independent of the material realm, entities which are entirely imaginary, outside the world of our five senses, and yet which seem to exist in some fashion, often sublimely connected with one another.  (The square root of minus 1, for example, is entirely imaginary, yet its properties are not random, to be invented as we might wish from whole cloth, but are decidedly what they are.)

For Norm, the material world is rich and interesting enough as it is, and needs no further explanation.   If you have ever experienced something beyond the material, then I suggest that finding an explanation or interpretation of that experience which makes some sense of it for you is not nothing, and is a quest not to be ridiculed or derided, however quixotic that quest might prove.




Crowd-sourcing for scientific research

Published
by
peter
on 2010-08-06
in Computer Science, Computer technology, Computing-as-interaction, Human intelligence, Joint-Action Society, Science and Team working
. Closed

Computers are much better than most humans at some tasks (eg, remembering large amounts of information, tedious and routine processing of large amounts of data), but worse than many humans at others (eg, generating new ideas, spatial pattern matching, strategic thinking). Progress may come from combining both types of machine (humans, computers) in ways which make use of their specific skills.  The journal Nature yesterday carried a report of a good example of this:  video-game players are able to assist computer programs tasked with predicting protein structures.  The abstract:

People exert large amounts of problem-solving effort playing computer games. Simple image- and text-recognition tasks have been successfully ‘crowd-sourced’ through games, but it is not clear if more complex scientific problems can be solved with human-directed computing. Protein structure prediction is one such problem: locating the biologically relevant native conformation of a protein is a formidable computational challenge given the very large size of the search space. Here we describe Foldit, a multiplayer online game that engages non-scientists in solving hard prediction problems. Foldit players interact with protein structures using direct manipulation tools and user-friendly versions of algorithms from the Rosetta structure prediction methodology, while they compete and collaborate to optimize the computed energy. We show that top-ranked Foldit players excel at solving challenging structure refinement problems in which substantial backbone rearrangements are necessary to achieve the burial of hydrophobic residues. Players working collaboratively develop a rich assortment of new strategies and algorithms; unlike computational approaches, they explore not only the conformational space but also the space of possible search strategies. The integration of human visual problem-solving and strategy development capabilities with traditional computational algorithms through interactive multiplayer games is a powerful new approach to solving computationally-limited scientific problems.”

References:

Seth Cooper et al. [2010]: Predicting protein structures with a multiplayer online game.  Nature, 466:  756–760.  Published:  2010-08-05.

Eric Hand [2010]:  Citizen science:  people power.  Nature 466, 685-687. Published 2010-08-04.

The Foldit game is here.

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Doing a PhD

Published
by
peter
on 2010-02-17
in AI, Computer Science, Decision theory, Science and Writing
. 1 Comment

These are some notes on deciding to do a PhD, notes I wrote some years ago after completing my own PhD.

Choosing a PhD program is one of the hardest decisions we can make. For a start, most of us only make this decision once in our lives, and so we have no prior personal experience to go on.

Second, the success or otherwise of a PhD depends a great deal on factors about which we have little advanced knowledge or control, including, for example:

Continue reading ‘Doing a PhD’




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