Science fiction shows the way: In series like "Star Trek" spaceships move faster than light. According to the theory of relativity this cannot and must not be the case. Could there still be a way?
Berlin – He clearly defined the physical limits of our world: Albert Einstein, Nobel laureate and one of the most important natural scientists in history, presented his theory of relativity more than 100 years ago.
"It’s not possible to be faster than light." With these words, physicist and science fiction expert Sascha Vogel summarizes an important aspect of the work of the ingenious researcher. That means: A spaceship cannot accelerate to "faster than light speed" by itself.
But maybe a trick will help? The model comes from science fiction: at the end of the first episode of the cult series "Star Trek," broadcast in 1966, Captain Kirk gives the order to go to "Warp 1. The wiki for the Adventures of the Starship Enterprise, titled "Memory Alpha," defines this as "faster than light speed".
A wave that bends space-time
Mexican physicist Miguel Alcubierre claims to have found a loophole to make this happen in real life- at least in theory. The move in his "Alcubierre drive": Not the spacecraft, i.e. the matter itself, is accelerated, but the space around it is artificially curved.
That means: The vehicle hardly moves at all, but travels in a so-called warp bubble through the universe. Figuratively explained: the spaceship rides a wave that bends spacetime, shortening its path.
Physicist Vogel still sees "many ifs and buts" with this idea. A prerequisite for the "Alcubierre drive" would be about „negative energy" – although it is not yet clear whether they exist at all. A negative energy flow, physics experts suspect, could arise at the edge of a black hole, for example.
Alternative: Exceptionally much conventional energy
"Things are only impossible until they are no longer so." Kirk’s successor, Captain Jean-Luc Picard, explains in the series "Star Trek – The Next Century" how circumstances change when innovations are present. For it is clear that if travel to distant stars is to be possible at all within the lifetime of a human being, such a drive would have to be found.
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In any case, a researcher at the University of Gottingen is trying a different approach. Astrophysicist Erik Lentz for example managed to get along without "negative energy" in his considerations. "Currently, there is no proven way to produce them even in microscopic quantities," Lentz explains.
Its solution: there would have to be an extraordinary amount of conventional energy available. On this basis, the island could then Space travel to Proxima Centauri, which is about 4.2 light-years away faster than is currently possible- the nearest star outside our solar system.
By comparison, the Voyager 1 spacecraft, launched in 1977 and which has now left our solar system and traveled more than 23 billion kilometers, would take about 75.000 years.
Can such an energy demand be met at all?
The challenge: The energy required for this new type of space propulsion would be huge. Lentz speaks of an "astronomical energy source".
The scientist explains: "The energy required to drive a spacecraft with a radius of 100 meters to the speed of light is of the order of a hundred times the mass of the planet Jupiter."Einstein’s famous equation E=mc² states that mass (m) and energy (E) can be converted into each other.
Jupiter is about 2.5 times as heavy as the rest of the planets in our solar system combined. The earth would fit in 318 times. This means that, according to Lentz’s theory, the spaceship, which is about 100 meters tall, would have to have much more mass, or pretend to have more mass, than it actually has. How this is to succeed, however, is still an open question.
Implementation of the theory would be sensational
The theoretical consequence of this large mass would be, however, that the space in front of the vehicle curves. The spaceship would fly into the curvature, would have moved with it only minimally and would come out again light years away in a distant galaxy. So it itself would have moved only a little, but would have advanced a much further distance through the curvature of space than can be accomplished with today’s drives.