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Dark energy spacecraft could fly faster than light

Monday, 18 August 2008
Cosmos Online

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Warp drive

Full speed ahead: Warp field according to the Alcubierre drive. Image shows the opposing regions of expanding and contracting spacetime that propel the central region.

Credit: Wikimedia

SYDNEY: A futuristic engine that uses dark energy to propel a spaceship faster than light is theoretically possible, and could revolutionise space travel, U.S. scientists say.

The idea, backed up by calculations made by physicist Gerald Cleaver and graduate student Richard Orbousy, both of Baylor University in Waco, Texas, was published online on the arXiv.org physics website.

Not as unlikely as it seems

Like something from the world of Star Trek, their theory says that a spacecraft could travel at 'warp speed' in a bubble of space-time by manipulating dark energy, the mysterious invisible force accelerating the expansion of the universe (see, More evidence for dark energy's repulsive power, Cosmos Online).

The spacecraft would essentially remain in the same place, they said, while space-time ahead of the spaceship shrank, and expanded again behind it.

The warp engine is based on the 'Alcubierre warp drive', a mathematical model of a method of stretching space in a wave that was first proposed by Mexican physicist Michael Alcubierre in 1994.

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

The concept is based on new predictions emerging from string theory (a branch of theoretical physics which states that reality is based on one-dimensional objects called strings). String theorists believe space has not three or four but 10 dimensions: height, width, length, time and others that are unknown (see, A way to 'see' extra dimensions, Cosmos Online).

M-theory

M-theory, which is as yet untested, unifies the various string theories by adding a further, 11th, dimension. Manipulating this 11th dimension exploits a loophole in Einstein's theory of relativity that says that travelling at faster-than-light speeds would take an infinite amount of energy.

"String theory suggests that dimensions are globally held compact by strings wrapping around them," the researchers write in their paper. "If this is the case, it may be possible to locally increase or decrease the string tension," they theorise, changing the size of the extra dimensions.

Theoretical astrophysicists think that at the beginning of time, dark energy may have driven the universe to grow at faster than light speed for a short time.

Readers' comments

Science of physics in highspeed travel

It seems that the universe has some secrets as man ,and high tecnology have opened some doors that unlimit the old limitations.

What dark energy?

The whole dark matter/dark energy concept is a patch up band-aid to save big bang from the dustbin of scientific history. It is futile. Einstein’s field equations for the static vacuum gravitational field, i.e. Ric = 0,violates his ‘Principle of Equivalence’ – the equivalence of gravitational and inertial mass, and the laws of Special Relativity, cannot manifest in a spacetime which is by definition empty, that contains no matter. QED. Consequently, if his energy-momentum tensor is zero there is no Einstein gravitational field. Hence his field equations take the following form:

Gij/k + Tij = 0, (subscripts)i,j = 0,1,2,3, k = constant,

wherein the Gij/k are the components of a gravitational energy tensor. Thus the total energy of the gravitational field is always zero; the Gij/k and Tij must vanish identically; there is no possibility for the localisation of gravitational energy (i.e. there is no possibility for Einstein’s gravitational waves). Moreover, this means that Einstein’s General Theory of Relativity violates the experimentally well established conservation of energy and momentum, so if the usual conservation of energy and momentum is valid (bearing in mind that there is no experimental evidence to refute it) then Einstein’s General Theory of Relativity is invalid. Also, Einstein invented his pseudo-tensor by which he and subsequent big bangers and LIGOers claim that his gravitational energy can be localized. However, Einstein’s pseudo-tensor is a meaningless concoction of mathematical symbols for the following reason – it implies the existence of a 1st-order intrinsic differential invariant which depends only upon the components of the metric tensor and their 1st-derivatives (to see this just contract his pseudo-tensor and apply Euler’s theorem). But the pure mathematicians G. Ricci-Curbastro and T. Levi-Civita proved in 1900 that such invariants do not exist! In addition, Einstein and the subsequent big bangers and LIGOers resort to linearisation of Einstein’s field equations to localize his gravitational energy. This too is nonsense, because linearisation implies the existence of a tensor which, except for the particular case of being precisely zero, does not otherwise exist, as proven by H. Weyl in 1944. So the big bangers and the LIGOers and their international counterparts such as the AIGO in Australia and VIRGO in Europe, are all destined to detect nothing.

As for black hole collisions, mergers and binaries producing gravitational waves, that too is nonsense by the foregoing. To amplify, let’s assume for the sake of argument that black holes are predicted by General Relativity. The simplest black hole is the so-called “Schwarzschild black hole”, obtained from Ric = 0, which is a statement that there is no matter in the Universe. Since the ‘Principle of Superposition’ does not apply in Einstein’s theory, owing to it being non-linear, one cannot, by an analogy with Newton’s theory (where the Principle of Superposition holds), just arbitrarily insert lumps of matter into any given spacetime for his gravitational field. Now according to the black holers and gravitational wavers , two “Schwarzschild” black holes (concocted by stupidly applying the ‘Principle of Superposition’ of Newton’s theory), each obtained separately from Ric = 0 (an empty spacetime), can mutually interact in a mutual spacetime that by definition contains no matter! That is nonsense, but the simplicity of it escapes their poor brains. However the issue is moot, since black holes are in fact forbidden by the Theory of Relativity (it forbids infinite densities), and owing to the violation of the usual conservation of energy and momentum, General Relativity is invalid.

Are you having another suggestion?

Last time I read according to string theory have 11 dimensions, now I read have 26 dimensions. It seems that the inflation reach to science, may be the economic situation have influence that we don't knows.

Dark energy
Dark matter
Multi universes
Multi dimensions
Entanglement

Are you having another suggestion?