Warp drive or how to beat the speed of light

“Infinity and beyond!” Buzz Lightyear shouts at Toy Story (1995), as the promise of a future trip through the stars… and the long-awaited one. at Star TrekCreated by Gene Roddenberry in 1966, Distortion allows the ship to travel countless distances in no time. A very practical technology for a human member of the Federation, an Interplanetary Republic spanning a radius of 8000 light years… A bold idea and not completely crazy! According to Einstein’s theory of relativity, nothing within our spacetime can exceed the speed of light – about 300,000 km/s. But what about space-time itself? Thus, the young universe seemed to have experienced a phase of inflation, which made it “inflate” exponentially like a balloon! Result: the distance between two points has increased dramatically and without violating the laws of relativity. Miguel Alcubierre, Mexican theoretical physicist, inspired by this phenomenon on a much smaller scale, proposing its model from warp drive. An almost poetic concept, but so theoretical that it seems far removed from current payment technologies…

From chemical propulsion to fusion propulsion

Today, space launches are all about extracting payloads –Satellites, sensors – gravitational field for tr. To lift these thousands of tons, engineers rely on chemical propulsion based on liquid (oxygen – kerosene) or solid (mineral powders) fuels, allowing for extremely powerful thrust. Problem: The specific impulse, which provides information on fuel consumption, is too low. In other words, the mass of fuel used is enormous – from 90 to 95% of the total mass of the rocket! To go far in the coming years, work is underway on thermonuclear propulsion. The idea? Replace combustion reactions with nuclear fission, for a specific batch multiplied by 2. But to hope moving forward, it will be necessary to limit consumption further. For this, a technology exists: ionic propulsion. “The principle is a miniature particle accelerator. The particles are ionized first, before accelerating them using electric or magnetic fields,” explains Stefan Mazover, a plasma and fuel physicist at the CNRS’s ICARE Laboratory. The thrust is restrained, but the specific thrust is tens of times larger than the chemical version, since the mass is divided by 2 in the case of a communications satellite.

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A real revolution could come in terms of efficiencysun sails. In fact, these systems do not require fuel or an internal source of energy. These are solar photons that push the sail toward interstellar space. However, the further you go, the less significant the resulting acceleration becomes. Hence the need for shots lasercentered, or sails several hundred kilometers² – It’s unimaginable these days. But the Holy Grail of Stéphane Mazouffre is quite different: “Propulsion by thermonuclear fusion would combine the best chemical and ionic methods, allowing for a very powerful propulsion for a very low consumption”. It would therefore be necessary to successfully create the fusion plasma. An easier task than ground-based reactors, and the goal is not to get energy but simply use it. However, the process has not yet been clarified … So, what are the chances we have left to overcome the barrier, a priori Impassable, 300,000 km / sec?

Is it a game that distorts spacetime?

In 1994, Miguel Alcubierre spent his spare time developing an ultrafast space travel model: the warp drive, which is the distortion of spacetime. In general relativity, the latter is assumed to be curvilinear. Visible property during eclipse. “The light rays of distant stars then deviate from the Sun, changing their apparent position in the sky,” describes Jerome Novak, a researcher at the Laboratory for Cosmos and Theory (LUTH). Einstein’s equation makes it possible to measure this curvature, by relating it to the content of matter. If we know the mass, then we can estimate the gravitational force at certain points. However, Miguel Alcubierre does a job Reverse thinking: If I want a certain weight in a certain place, how much material do I need? In fact, his idea consists of an artificial inflation mechanism. To allow a spacecraft to move at a very high speed, the physicist proposes extending spacetime at the back of the spacecraft, and shrinking it in front. From this perspective, it defines spacetime with the right properties. Thus he avoids major pitfalls such as monstrous tidal forces – the equivalent of a black hole – or time anomalies between pilot and observer … But other concerns resist his calculations.

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First of all, the warp drive It would require a huge amount of energy – perhaps on the order of the mass of the Sun! Subsequently, such a device will require the use of foreign materials, i.e. A type of substance that violates the principle of positive energy. “An empirical principle that has been violated only at the quantitative level, for example with the Casimir effect, so far,” Jerome Novak supports. In recent years, three articles have addressed the work of Miguel Alcubierre in an attempt to free themselves from the problem of negative energy. But their solutions have been called into question by New Zealand physicist Matt Visser and his colleagues. In fact, they display a single monitor that measures positive energy. However, all potential observers should receive the same power. Unfortunately for these three works Matt Visser introduces observers with negative energy … How can we thus hope to reach a warp drive functional?

We must review warp drive?

Matt Visser and his colleagues suggest several solutions to problems warp drive. An example would be a matter of modifying the theory of gravity, with a version that accepts violations of positive energy. There are a number of alternative theories, including the chameleon theory, where large-scale effects differ from local ones. The researchers also suggest setting a space-time other than that chosen by Miguel Alcubierre. Why not, but let’s not forget that it allowed to remove many pitfalls. What if we approach the principle of positive energy head on and forget about it completely? Well, this would give way to folded spacetime curves, resulting in time travel! An individual at a point can turn before returning to the same point, and thus to the same place at the same time. An invitation to temporal paradoxes… The solution can ultimately lie in macroscopic quantum phenomena, if such a solution exists. Meanwhile, Stefan Mazover recalls: “We are not ready to escape during the coming centuries, so let’s protect our planet as much as possible.”