Star Trek warp drive is a possibility, say scientists

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Star Trek warp drive is a possibility, say scientists
By Roger Highfield, Science Editor
15/08/2008

Two physicists have boldly gone where no reputable scientists should go and devised a new scheme to travel faster than the speed of light.

The advance could mean that Star Trek fantasies of interstellar civilisations and voyages powered by warp drive are now no longer the exclusive domain of science fiction writers.

In the long running television series created by Gene Roddenberry, the warp drive was invented by Zefram Cochrane, who began his epic project in 2053 in Bozeman, Montana.

Now Dr Gerald Cleaver, associate professor of physics at Baylor, and Richard Obousy have come up with a new twist on an existing idea to produce a warp drive that they believe can travel faster than the speed of light, without breaking the laws of physics.

In their scheme, in the Journal of the British Interplanetary Society, a starship could "warp" space so that it shrinks ahead of the vessel and expands behind it.

By pushing the departure point many light years backwards while simultaneously bringing distant stars and other destinations closer, the warp drive effectively transports the starship from place to place at faster-than-light speeds.

All this extraordinary feat requires, says the new study, is for scientists to harness a mysterious and poorly understood cosmic antigravity force, called dark energy.

Dark energy is thought responsible for speeding up the expansion rate of our universe as time moves on, just like it did after the Big Bang, when the universe expanded much faster than the speed of light for a very brief time.

This may come as a surprise since, according to relativity theory, matter cannot move through space faster than the speed of light, which is almost 300,000,000 metres per second. But that theory applies only to unwarped 'flat' space.

And there is no limit on the speed with which space itself can move: the spaceship can sit at rest in a small bubble of space that flows at "superluminal" - faster than light - velocities through normal space because the fabric of space and time itself (scientists refer to spacetime) is stretching.

In the scheme outlined by Dr Cleaver dark energy would be used to create the bubble: if dark energy can be made negative in front of the ship, then that patch of space would contract in response.

"Think of it like a surfer riding a wave," said Dr Cleaver. "The ship would be pushed by the spatial bubble and the bubble would be travelling faster than the speed of light."

The new warp drive work also draws on "string theory", which suggests the universe is made up of multiple dimensions. We are used to four dimensions - height, width, length and time but string theorists believe that there are a total of 10 dimensions and it is by changing the size of this 10th spatial dimension in front of the space ship that the Baylor researchers believe could alter the strength of the dark energy in such a manner to propel the ship faster than the speed of light.

They conclude by recommending that it would be "prudent to research this area further."

But hold the dilithium crystals: Dr Chris Van Den Broeck of Cardiff University commented: "The problem with this and previous schemes (including my own) is that part of the exotic matter would have to travel faster than the *local* speed of light (roughly speaking, it would need to go faster than the speed of light with respect to the portion of space it occupies), and that's not allowed by any established physical theory."

And even if this criticism can be met, Richard Obousy computed the amount of energy required to start up a "warp" process (but not the total energy required to travel a specific distance) around a 10x10x10 metre-cube ship based on the required change in dark energy in a space equal to the volume of the ship.

The energy to kick start the drive turned out to be equivalent to turning the entire mass of Jupiter into energy, by Einstein's famous E equals Mc squared equation, where c is the speed of light. Given the mass of Jupiter is around 2000,000,000,000,000,000,000,000,000 kilograms, that is a big number.

"That is an enormous amount of energy," Dr Cleaver said. "We are still a very long ways off before we could create something to harness that type of energy."