Protagonists: Actors Sam Rockwell and Zooey Deschanel at the premiere of Hitchhiker’s Guide in London; (below) Douglas Adams

The answer to life, the Universe and everything is 42, according to The Hitchhiker’s Guide to the Galaxy. Writing the classic sci-fi fantasy in 1978, Douglas Adams conjectured that everything known about the cosmos could be reduced to a few numbers. It was a good philosophical joke.

More than 20 years later Sir Martin Rees, the astronomer royal, suggested the ultimate answer might boil down to six figures. The theory for everything is the new holy grail, proving that Adams’s sense of the absurd has come full circle.

Adams is now acknowledged as an accidental visionary who tapped into 1970s scientific debates that, spookily, have become some of today’s cutting-edge issues. As Hitchhiker’s Guide gets the full Hollywood treatment in a film, the Science Museum in London has mounted an exhibition devoted to his creations from May 28.

It is a very British tribute to the amateur-scientist-turned-geek who dreamt up such whimsical fantasies as talking mattresses, triple-breasted prostitutes and the Babel fish, a small creature that could be slipped into the ear to provide simultaneous translation of any language in the Universe. The name Babel fish has been appropriated by a website that performs translations and Arthur Dent, Adams’s fictional protagonist, was adopted in 2001 as the name for an asteroid.

In the original radio series and later novels, Dent is one of a handful of survivors after earth is demolished to make way for a hyperspace bypass. He travels through the galaxy with his friend Ford Prefect, a pretty young astrophysicist named Trillion, the two-headed former president of the galaxy and an inaccurate tourist guide entitled The Hitchhiker’s Guide to the Galaxy.

The fertile scientific imagination of Adams, who died in 2001 at the age of 49, beguiled some of the most serious minds. His friend Richard Dawkins, the Oxford zoologist, remains intrigued by the ‘infinity improbability drive’ that propelled Dent’s spaceship. It takes the truism that there is a near-infinity improbability that you could suddenly dematerialise and rematerialise somewhere else. The spaceship exploits infinity and probability in order to move around space by violating all laws of common sense and science. It’s not a theory, it’s just a joke.

Yet such a drive does fit with string theory, the so-called theory of everything. And teleportation has become a theoretical possibility since physicists managed to teleport electrons and even whole atoms from one side of the lab to the other. “If you can teleport an atom, maybe you can teleport a mouse or a whole human. But it does raise serious philosophical and ethical questions,” says James Rudoni, who is managing the Science Museum exhibition.

The Universe has turned out to be even stranger than Adams supposed more than two decades ago when he described space tourism and parallel universes. The particle physicist Michio Kaku, a leading proponent of string theory, suggested in his recent book Parallel Worlds that our Universe may be nothing less than a membrane hovering near 10 other parallel universes that multiply like soap bubbles when they collide.

Kaku’s theories echo Adams’s wildest imaginings. The recent discovery that ‘dark energy’ makes up 73 of our Universe and may be acting as an anti-gravitational force that is hastening our destruction, means we may have to escape down a man-made wormhole into a parallel Universe, Kaku claims.

The physicist’s escape plan depends on mankind developing a Type III civilisation capable of controlling the output of an entire galaxy. (Sounds familiar?) At present we rate as Type 0, deriving our energy from plants, oil and coal. The transformation willtake 100,000 to 1 million years, Kaku predicts.

Adams, an amateur scientist, was sometimes spot on. “Space,” said the Guide, “is very big. Really big. You just won’t believe how hugely mindbogglingly big it is.” It has since been found to be much bigger and older than anyone supposed. In 2003 the WMAP (Wilkinson Microwave Anisotropy Probe) put its age at 13.7 billion years.

The author was wide of the mark occasionally. Take Deep Thought, the huge computer which came up with the answer to life, the Universe and everything after 7.5 million years of cogitation. Informed that it had put the cart before the horse, Deep Thought then created the earth and its inhabitants as a giant calculating device to discover what the ultimate question was. Equating computing power with size is now an outdated concept.

If Adams had seriously tried to forecast the future, he would have picked up a 1965 prediction by Gordon Moore, the founder of the silicon chip giant Intel, that the power of computers would double every 18 months, cutting their size.

But sentience and the ability to calculate the ultimate answer still eludes the modern computer, Michael Hanlon points out in his new book The Science of the Hitchhiker’s Guide to the Galaxy. “It can perform several million calculations a second, but it’s no brighter than a cockroach.” On the other hand, Adams’s supercomputer was strangely prescient. Last year the astronomer royal raised the question of whether mankind itself was a computer simulation.

Much of the “science” in the Hitchhiker’s Guide is “clearly bonkers, and intentionally so”, says Hanlon. “Yet it bristles with science and technology. The Guide records Douglas Adams’s fascination with the increasingly strange twists and turns of cutting-edge cosmology and theoretical physics.” In the 1970s science was being popularised in such television programmes as Horizon and Adams’s acute ear was tuned in to the ideas floating around. He then gave them a ludicrous spin for comic effect.

Among his bizarre creations are flying office blocks and a spacecraft marooned for thousands of years where passengers are woken every century to be served refreshments while the crew wait for lemon-soaked napkins to be delivered. A square-wheeled bicycle makes an appearance on the planet Viltvodle, known for inventing the aerosol can before the wheel. He also liked to throw in tantalising philosophical questions, such as the existence of God. According to Adams, the Babel fish was proof that there was no creator. His reasoning was that God refused to prove his own existence, “for proof denies faith, and without faith I am nothing”. Adams’s Catch-22 goes on to argue that since the Babel fish could not have evolved by chance, it proves God exists, and therefore by God’s own arguments he doesn’t.

The atheist Dawkins, in a tribute to Adams after his death, recalled another of his religious jokes: “To illustrate the vain conceit that the Universe must have been somehow preordained for us, because we are so well suited to live in it, he mimed a wonderfully funny imitation of a puddle of water, fitting itself snugly into a depression in the ground, the depression uncannily being exactly the same shape as the puddle.” Adams told Dawkins a parable that explained much about the relationship of his humour to science. It concerned a man who did not understand how televisions work, and was convinced there must be little men inside manipulating the images at high speed.

“An engineer explained about high-frequency modulations of the electromagnetic spectrum, transmitters and receivers, amplifiers and cathode-ray tubes, scan lines moving across and down a phosphorescent screen. The man listened to the engineer with careful attention, nodding his head at every step of the argument. At the end he pronounced himself satisfied. He really did now understand how televisions work. ‘But I expect there are just a few little men in there, aren’t there?’”

Sometimes Adams reflected the prejudice of his time. Aliens were thought to be faintly risible in the 1970s, as was time travel. Today the radio telescopes of Seti, the Search for Extraterrestrial Intelligence, scan the heavens for signals from other civilisations. And scientific thinkers such as Stephen Hawking have rekindled the debate about whether it is possible to go back in time.

The Hitchhiker’s Guide depicted the spectacular end of creation, which could be viewed from the Restaurant at the End of the Universe. New research suggests that cosmic expansion will continue and stars will be born and die before the energy runs down and the lights flicker out. By then, the names of Adams’s creations may have shifted to more distant outposts of the firmament.

THE SUNDAY TIMES, LONDON