Monday, July 30, 2007

Fred Hoyle

[Previously posted at waagnfnp ]

Fred Hoyle was born in Yorkshire in 1914 to decidedly middle-class parents (a wool merchant and a teacher). He was probably the most prominent scientist to ever have a significant career as a science fiction writer, having written such books as The Black Cloud and A for Andromeda. In the latter novel, some scientists genetically engineer an alien woman based on DNA coding sequences they receive from a stellar transmission. The book was made into a 7 episode series for the BBC, then the idea was pinched for the movie Species.

Hoyle is popularly known for his coinage of the term “Big Bang” and for his opposition to the Big Bang Hypothesis; he believed in “Continuous Creation” and held to it long after the discovery of cosmic background radiation and the more-or-less complete adoption of the BBH by the entire astronomical community. Not content to be something of a crank on the Big Bang, he also put forth the theory of panspermia as an alternative to terrestrial evolution. Panspermia essentially holds that life first occurred in space, and then came to planets; its strong form holds that evolutionary changes rain down from space as viruses or something similar. It is held in high regard in some Creationist circles, though I have no idea why genetic changes from space viruses are more in keeping with Creationist logic (or lack of it) than terrestrial mutations.

It’s possible that Hoyle’s anti-establishmentarian mind-set cost him the Nobel Prize. Hoyle’s co-worker, William Fowler, won the Nobel in 1963, essentially for confirming Hoyle’s prediction of a resonance level in the carbon nucleus, a prediction that Hoyle made as a result of a problem in nucleosynthesis of heavy elements in stars. (It may be noted that Hoyle made the prediction as part of his program to explain heavy elements as being a natural result of stellar nucleosynthesis, something that was absolutely essential if continuous creation was to be viable).

The problem that Hoyle was working on involved the nuclear fusion of elements past helium. The difficulty is that, if you try to fuse helium, you get beryllium-8, which almost immediately fissions back into two helium nuclei. So helium looks like a dead end. The only way out seemed to be if another helium nucleus hit the Be-8 during its very short lifetime. Unfortunately, calculations showed that the resultant highly energetic carbon-12 nucleus would also break apart. Indeed, the nuclear formation of Be-8 (from a Li-7 plus a proton, say), or C-12 (boron-11 plus a proton) form the basis of proposals for “light fission” nuclear power, because the created nuclei fly apart to He-4, liberating considerable energy.

Hoyle decided that there had to be a “nuclear resonance” in carbon-12 nuclei, that sometimes allowed the stable formation of C-12 from the Be-8 + He-4 reaction. Fowler later measured that resonance and found it to be only a few percent off Hoyle’s calculations.

It was about as daring a prediction as has ever been made in science, combining nuclear physics, astronomy, and the anthropic principle (Hoyle reasoned that he was made of carbon, therefore there must be a way for carbon to be formed), along with the simple bloody-mindedness of trying to support a doomed theory, continuous creation.

Hoyle was eventually knighted, and is doubtless much more famous than his co-workers, or, for that matter, Alpher, Bethe, and Gamov, who formulated the Big Bang hypothesis, but didn’t name it as such. Hoyle also championed Jocelyn Bell, as the real discoverer of pulsars (her Ph.D. advisor was awarded the Nobel), again showing perhaps the effects of not being from quite the right social class for British science.

Of Hoyle’s novels, only The Black Cloud seems to be in print, but many of his others can be found used; I was always fond of October the First Is Too Late. I’d also recommend Element 79, a collection of short stories, for often providing just loopy good fun.

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