General Relativity states that space and time are fused and that nothing can travel faster than the speed of light. General relativity also describes how mass and energy warp spacetime — hefty objects like stars and black holes curve spacetime around them. Early science fiction writers John Campbell and Asimov saw this warping as a way to skirt the speed limit. What if a starship could compress space in front of it while expanding spacetime behind it?
In , Miguel Alcubierre, a Mexican theoretical physicist, showed that compressing spacetime in front of the spaceship while expanding it behind was mathematically possible within the laws of General Relativity. So, what does that mean? Imagine the distance between two points is 10 meters 33 feet. If you are standing at point A and can travel one meter per second, it would take 10 seconds to get to point B.
Then, moving through spacetime at your maximum speed of one meter per second, you would be able to reach point B in about one second. In theory, this approach does not contradict the laws of relativity since you are not moving faster than light in the space around you. Proxima Centauri here we come, right? The warp drive would require either negative mass — a theorized type of matter — or a ring of negative energy density to work. Physicists have never observed negative mass, so that leaves negative energy as the only option.
To create negative energy, a warp drive would use a huge amount of mass to create an imbalance between particles and antiparticles. For example, if an electron and an antielectron appear near the warp drive, one of the particles would get trapped by the mass and this results in an imbalance. This imbalance results in negative energy density. But for a warp drive to generate enough negative energy, you would need a lot of matter.
Alcubierre estimated that a warp drive with a meter bubble would require the mass of the entire visible universe.
Alcubierre describes spacetime expanding on one side of the ship and contracting on the other, thanks to that enormous amount of energy and a requisite amount of exotic matter—in this case, negative energy.
Some scientists have criticized the Alcubierre drive, however, because it requires too much mass and negative energy for humans to ever seriously construct a warp-based propulsion system. The physical model uses almost none of the negative energy and capitalizes on the idea that spacetime bubbles can behave almost however they like. Plus, Alcubierre himself has endorsed the new model, which is like having Albert Einstein show up to your introductory physics class.
Type keyword s to search. Today's Top Stories. A new paper proposes a fully physically realized model for warp drive. This builds on an existing model that requires negative energy—an impossibility. Mario Borunda does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
The closest star to Earth is Proxima Centauri. It is about 4. The fastest ever spacecraft, the now- in-space Parker Solar Probe will reach a top speed of , mph. If humanity ever wants to travel easily between stars, people will need to go faster than light. But so far, faster-than-light travel is possible only in science fiction. As a kid, I read as many of those stories as I could get my hands on.
I am now a theoretical physicist and study nanotechnology, but I am still fascinated by the ways humanity could one day travel in space. Warp drives are theoretically possible if still far-fetched technology. Two recent papers made headlines in March when researchers claimed to have overcome one of the many challenges that stand between the theory of warp drives and reality. But how do these theoretical warp drives really work? And will humans be making the jump to warp speed anytime soon?
General Relativity states that space and time are fused and that nothing can travel faster than the speed of light. General relativity also describes how mass and energy warp spacetime — hefty objects like stars and black holes curve spacetime around them.
Early science fiction writers John Campbell and Asimov saw this warping as a way to skirt the speed limit.
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