Friday, 24 August 2007

Not this, not that

Good old New Scientist magazine. I've read almost every issue since my school days, and it's one of the joys of my life. It does occasionally veer towards the somewhat loopy (see this criticism by SF writer GregEgan), but it can't be easy producing a weekly magazine that has to contain at least one article per issue of cosmological significance. When I say I've read every issue, I do tend to skip quite lightly over any article with a first sentence containing the word may, such as: "Scientists may have discovered...", because almost inevitably there'll be a letter the next week from an expert in the field explaining why they've discovered no such thing. I remember one article, many years ago, that was very excited about an experiment which, if true and repeatable, would have demonstrated the action of mind-over-matter, showing someone influencing the sequence in which a series of light-bulbs lit up, the sequence being otherwise controlled by the random decay of radioactive atoms. I waited in vain for the laws of physics to be rewritten.

The latest example of this seems to me to be the front-page article in the 18th August issue claiming that "cosmologists are afraid - very afraid" of something called Boltzmann Brains. These are supposed to be a consequence of the non-emptiness of empty space. The quantum vacuum is seething with virtual particles and, given enough space and time, these particles may configure themselves into a spooky conscious entity - a Boltzmann Brain.

Are you worried yet? It gets scarier (if you're a cosmologist with nothing more immediate to worry about). They are concerned that, in an inflationary universe (such as ours appears to be), there will be enough time (i.e. a few trillion years), for these entities to outnumber evolved consciousnesses (i.e. us), and then where would we be? The laws of physics depend on us being the typical observers of the universe, not these disembodied "brains" that would probably have a rather different take on what makes things tick.

Incidentally, for what it's worth, my take on the accelerating expansion of the universe, which physicists ascribe to the presence of "dark energy", is a bit different. My view is that the accelerated expansion is a result of an attractive force from whatever it is that our universe is surrounded by and is expanding into. You read it here first!

Anyway, I wouldn't lose too much sleep over Boltzmann Brains. This is a variation of the argument that, in an infinite universe, anything can (and therefore will, eventually) happen. Given enough monkeys with enough typewriters, paper and time... lo and behold, one of them will produce the complete works of Shakespeare. Well, no they won't. There aren't enough atoms in the universe to make enough monkeys to create, by chance, even something as modest as this blog posting.

I have to be a bit careful mocking the infinite-monkey argument. Creationists deploy similar statistical arguments to "prove" that life could not have arisen purely by chance. Fortunately, Richard Dawkins, in his book The Blind Watchmaker, effectively demolishes this case for intelligent design. The monkeys produce strings of letters, and evolutionary pressure and a genetic mechanism select and preserve these (not a so-called intelligent designer).

Dawkins, incidentally, comes in for some criticism in the latest issue of New Scientist, taken to task by Lawrence Krauss for being too emotive in his latest "Proud to be Atheist" campaign. My only criticism of Dawkins is for not using humour more effectively. In his latest TV series (Enemies of Reason, Channel 4) he misses some golden opportunity to make more fun of his subjects. He lets the various astrologers and crystal healers off very lightly. And wasn't he tempted to ask the homeopath whether, in the case of a really really bad headache, he should take some water with that homeopathic "remedy" to further dilute it and make it even stronger?

Speaking of TV, is anyone else as annoyed as I am by BBC2's weather report format? Who decided that it would be a good idea to overlay the map with an opaque stencil of the channel logo, thus sacrificing screen estate and creating quite a disconcerting effect when the map moves underneath it? Talk about style over content...

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