Skip to main content

Dark Matter and the Dinosaurs - Lisa Randall ****

I did my PhD in galactic dynamics - which is an awkward subject when people want to know what its relevance to the 'real world' is. So I was excited when Clube and Napier's book The Cosmic Serpent came out, around the same time, because it provided me with a ready-made answer. It argued that the comets which occasionally crash into Earth with disastrous results - such as the extinction of the dinosaurs - are perturbed from their normal orbits by interactions with the large-scale structure of the galaxy.

I was reminded of this idea a few years ago when there was a flurry of media interest in Lisa Randall's "dark matter and the dinosaurs" conjecture. I was sufficiently enthusiastic about it to write an article on the subject for Fortean Times - though my enthusiasm didn't quite extend to purchasing her hardback book at the time. However, now that it's out in paperback I've remedied the situation - and I'm glad I did.

Dark matter is believed to exist in large quantities in the galaxy, but it's very difficult to detect because it only interacts with ordinary matter through gravity. Most astrophysicists assume it only interacts with itself in this way, too, which means it has no way of dissipating energy. Randall, on the other hand, posits that a subset of dark matter can somehow dissipate energy - causing it to collapse down into an extremely thin disc. The gravitational effect of this disc then produces a perturbing effect on cometary orbits. According to Randall, only this model - rather than one involving ordinary matter or 'conventional' dark matter - is capable of providing a perturbation of the necessary magnitude.

This is the kind of science I find fascinating - involving a long chain of argument from one observable phenomenon, via a whole bunch of unobservable things, to another, seemingly unrelated, observable effect. It's pure speculation, of course (and probably wrong) but at least it's logical. That's what sets it apart from the kind of superficially similar speculation you find in sci-fi movies and Velikovsky-style pseudoscience.

My only criticism of the book is that it's too long. It's almost three books in one, in fact. First there's a popular science primer on cosmology, dark matter and galactic structure. Then there's a second popular science book - this time on asteroids, comets, impact events and mass extinctions. Finally there's the detective story tracing the cause of these extinctions to an exotic new kind of dark matter. Personally, I only wanted to read the third book. Even with some essential scene-setting at the start, that could easily have been achieved in half the book's 412 pages. The result would have been more exciting and more unique - and I probably would have given it five stars instead of four.



Review by Andrew May


Popular posts from this blog

The Feed (SF) - Nick Clark Windo ****

Ever since The War of the Worlds, the post-apocalyptic disaster novel has been a firm fixture in the Science Fiction universe. What's more, such books are often among the few SF titles that are shown any interest by the literati, probably because many future disaster novels feature very little science. With a few exceptions, though (I'm thinking, for instance, The Chrysalids) they can make for pretty miserable reading unless you enjoy a diet of page after page of literary agonising.

The Feed is a real mixture. Large chunks of it are exactly that - page after page of self-examining misery with an occasional bit of action thrown in. But, there are parts where the writing really comes alive and shows its quality. This happens when we get the references back to pre-disaster, when we discover the Feed, which takes The Circle's premise to a whole new level with a mega-connected society where all human interaction is through directly-wired connections… until the whole thing fails …

Everything You Know About Space Is Wrong - Matt Brown ****

What we have here is a feast of assertions some people make about space that are satisfyingly incorrect, with pithy, entertaining explanations of what the true picture is. Matt Brown admits in his introduction that a lot of these incorrect facts are nitpicking - more on that in a moment - but it doesn't stop them being delightful. I particularly enjoyed the ones about animals in space and about the Moon.

Along the way, we take in space exploration, the Earth's place in space, the Moon, the solar system, the universe and a collection of random oddities, such as the fact that Mozart didn't write Twinkle, Twinkle Little Star. Sometimes the wrongness comes from a frequent misunderstanding. So, for example, Brown corrects the idea that Copernicus was the first to say that the Earth moves around the Sun. Sometimes there's some very careful wording. This is used when Brown challenges the idea that the Russian dog Laika was the first animal in space. What we discover is that, i…