04 setembro 2009

The Science Book Club

Freeman Dyson explores the farthest limits of human imagination

In his book Imagined Worlds, Dyson glimpses a distant future in which humans communicate by radiotelepathy and terrestrial life has spread out across the galaxy

You can't keep a good man down. In the current New York Review of Books, Freeman Dyson uses his assessment of Richard Holmes's The Age of Wonder (already known to club members) to propose that we might be about to enter a new Romantic age, driven by biology and computing, in which a new generation of artists would "write genomes as fluently as Blake and Byron wrote verses".

Dyson was ever one to contemplate the very long-term potential of science. In 1972, before even the first genetic manipulation experiments, delivering the Bernal lecture at Birkbeck College in London he promised his audience that humankind would one day learn to grow trees on comets: it would only be a matter of redesigning the skin of the leaves to make them impervious to ultraviolet and to retain water, and a few other details.

Then, free of gravitational constraint, trees with compound leaves could grow to immense heights. "Seen from far away, the comet will look like a small potato sprouting an immense growth of stems and foliage. When man comes to live on the comets, he will find himself returning to the arboreal existence of his ancestors," he said.

At the time, such proposals sounded out of this world. They still do. But to call people like Freeman Dyson unworldly is to miss the point. Dyson had always argued that it is far better to be wrong than to be vague.

In Imagined Worlds (and the title is its own clue to the Dyson approach) the author thinks big: he takes an idea from somebody else, makes it his own and extends it further into the future than the rest of us could possibly imagine. For instance, in Last and First Men (1931) Olaf Stapledon imagined Martians as little green clouds composed of tiny droplets – sub-vital units that could transmit and receive fields, and serve as muscles and nerves to make the cloud behave as a coherent individual. It was a nice, spooky idea more than once picked up by movie-makers, but Dyson turns it into neurophysiology.

To understand what is going on in the brain we need "observing instruments that are local, non-destructive, and non-invasive, with rapid-response, high-bandwidth and high spatial resolution. We need to invent the terrestrial equivalent of a Martian sub-vital unit." And then he adds "There is no law of physics that declares such an observational tool to be impossible." And then with help from his sub-vital units, he proposes communication by radiotelepathy.

The difference between Freeman Dyson and people who write science fiction is that when Dyson talks about the laws of phsyics, you have no choice but to believe him. If the man who had an office down the corridor from Albert Einstein doesn't know the laws of physics, who does? So the contract between writer and reader in such cases moves to a different level. The imagination problem becomes not his, but ours.

Imagined Worlds dates from 1997: it's a case study in the limits of what even the finest scientists can foresee. The human genome project in that year was regarded as costly, clumsy and far from certain: many people thought it lunatic. Dyson imagines a world in which the genomic data becomes available at ever greater speeds, but he doesn't expect anyone to understand the architecture of inheritance in a hurry.

He also contemplates the enduring mysteries of galactic dark matter, but he is a year or so from knowing anything about the immensely more difficult problem of dark energy, the first intimation of which appeared in 1998. So he gets some things right, but is trumped by the discovery that 96% of the universe is composed of mysterious stuff, most of which has yet to be detected, let alone identified.

But so what? At bottom, Imagined Worlds is about what how we confront discovery: Dyson evokes HG Wells and The Time Machine; he examines Daedalus, a 1923 masterpiece of futurology by that great scientist and writer JBS Haldane, another man interested in the moral dimension of science; he takes a look at Aldous Huxley's Brave New World. He also quotes Bruce Chatwin, Saul Bellow, WH Auden and Neville Shute. He doesn't say so, but Dyson reminds us that he is in good company: Wells, Haldane and Huxley got things wrong, but they too preferred to be wrong rather than vague.

Dyson also takes his own direct look at the future, on scales of ten, a hundred, a thousand years when population, resources and living space will have grown by a factor of 500 million ("when life and industrial activities are spread out over the solar system, there is no compelling reason for growth to stop") and 10,000 years, and so on.

He also identifies the central problem for any intelligent society: the problem of sanity, which he defines as "the ability to live in harmony with Nature's laws", and yes, he finds the Gaia theory "plausible". He also thinks Gaian principles might operate beyond this planet, so that Earthling descendants and beings in other galaxies can cooperate "in large scale engineering projects to keep the universe in trim and maintain the optimum conditions for life".

The chapter on ethics is a reminder that scientific daydreams can be as wild as you like, but scientific reality operates in a world of evil and good, and as a general rule "science works for evil when its effect is to provide toys for the rich." He is thinking of nuclear weaponry, but fill in your own favourite misuse here.

I started re-reading this book expecting to be provoked into exasperation (Dyson once said that it was much more fun to be contradicted than ignored) but ended with a different response. The philosophical principle of maximum diversity, says Dyson, states "that the laws of Nature are constructed in such a way as to make the universe as interesting as possible."

I've never heard of the principle of maximum diversity. Maybe Dyson just made it up. But there's nothing dull about a universe with people like Dyson in it, and this book is as good a summary of the evidence for that statement as you could hope to find.

And from The New York Review of Books Dyson's article:

When Science & Poetry Were Friends

The Age of Wonder means the period of sixty years between 1770 and 1830, commonly called the Romantic Age. It is most clearly defined as an age of poetry. As every English schoolchild of my generation learned, the Romantic Age had three major poets, Blake and Wordsworth and Coleridge, at the beginning, and three more major poets, Shelley and Keats and Byron, at the end. In literary style it is sharply different from the Classical Age before it (Dryden and Pope) and the Victorian Age after it (Tennyson and Browning). Looking at nature, Blake saw a vision of wildness:

Tyger, tyger, burning bright,
In the forests of the night;
What immortal hand or eye,
Could frame thy fearful symmetry?

Byron saw a vision of darkness:

The bright sun was extinguish'd, and the stars
Did wander darkling in the eternal space,
Rayless, and pathless, and the icy earth
Swung blind and blackening in the moonless air....



The Science Book Club in The Guardian

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