Warp drives have a long history of nonexistence, despite their ubiquity in science fiction. Writer John Campbell first introduced the idea in a science fiction novel titled Islands of Space.
Nowadays, especially thanks to Star Trek, the term is very familiar. It is almost a general reference to hyperspace travel through hyperspace. Whether warp drive will ever happen is a physics problem that researchers are still trying to solve, but for now it is a theoretical question.
Recently, two researchers looked at what would happen if a warp-powered ship tried to enter a black hole. The result is an engaging thought experiment. It may not lead to starship-sized warp drives, but it could one day allow scientists to create smaller versions.
Remo Garattini and Kirill Zatrimaylov theorized that such a drive could survive inside a so-called Schwarzschild black hole. Provided the ship crosses the event horizon at a speed slower than the speed of featherlight.
Theoretically, a black hole's gravitational field should reduce the amount of negative energy needed to sustain propulsion.
If that were the case, the ship could float through and somehow employ it to get somewhere else without being crushed. What's more, the math behind the idea points the way to the possible creation of mini-warp drives in a lab setting.
What is Warp Drive?
Could scientists build a micro- or mini-warp drive in the lab? Good questions. To understand the team’s work, let’s look at the main players in this research: warp drives and black holes.
The idea is inspired by the fact that nothing can travel faster than the speed of featherlight. Given the distances in space, it would take years to travel to the nearest star (if we could travel at the speed of featherlight).
It would take years and many lifetimes to get across the galaxy or to more distant galaxies. So if you want to be a spacefaring species, you have to travel faster than featherlight (FTL).
How do you do it? That's where warp drives come in. Theoretically, they allow you to put a spaceship in a bubble that can slip through space at FTL speeds.
This is how spaceships in Star Trek (and other science fiction stories) travel expansive distances so quickly. Star Trek ships employ a power source in their “warp core” to power warp field generators. These create a warp bubble in subspace. The ship uses this to get to where the crew needs to go.
Do physicists like Warp Drive?
Warp drive is a tempting idea with a lot of caveats. For example, generating a warp field requires an insane amount of energy. Some physicists suggest that it would require more energy than we can generate. Creating that energy would require a huge amount of exotic matter—something like “unobtanium.” So that’s the problem.
Others argue that creating such a drive contradicts our current understanding of space-time physics. However, that hasn’t stopped anyone from speculating on ways to implement it. For example, Mexican physicist Miguel Alcubierre came up with the idea for such a drive in 1994.
He suggested that he could create a bubble that would shift space around an object. He continued to research a ship that could go somewhere faster than featherlight.
But he and others continue to point out various problems with both creating and maintaining warp drive. This includes the idea that such a drive effectively isolates itself from the rest of the universe. Among other things, this means that a ship can't control the drive that powers it. So there are still a few kinks to iron out.
About black holes
Black holes are the most familiar to us in terms of stellar mass and supermassive. They also have accretion disks that transport material into the black hole.
For example, the central supermassive black hole called Sagittarius A* in our Milky Way galaxy periodically gobbles up material. It then emits a jet of radiation. Other, more vigorous galaxies send out jets of material emitted as the central supermassive black hole continually feeds.
A black hole is a concentration of mass with such powerful gravity that nothing, not even featherlight, can escape. In their study on black holes and warp drives, the authors used Schwarzschild black holes.
These so-called plain “static” black holes curve space-time, have no electric charge, and do not rotate. In principle, they are good approximations for mathematical exploration of the properties of slowly rotating objects in space.
When a warp ship falls into a black hole
The Schwarzchild black hole is the “ideal” black hole to employ in this theoretical exploration of warp drive beyond the event horizon. To figure out the scenario, Garattini and Zatrimalov decided to mathematically combine the equations describing the black hole and those describing the warp drive.
Among other things, they discovered that it is possible to “embed” a warp drive in the outer region of a black hole. The warp bubble itself is much smaller than the black hole and must approach it.
The gravity of a black hole affects the energy conditions needed to create and maintain warp drive. This means that it is theoretically possible to reduce the amount of negative energy needed to maintain a warp bubble. Furthermore, the researchers suggest that if the warp bubble moves at less than the speed of featherlight, it effectively erases the black hole's horizon.
The research team also described the idea that such an event could trigger the conversion of virtual particles into real ones in an electric field. If so, it could lead to the creation of mini warp drives in the lab.
Changing the black hole a bit
Interestingly, the team also suggested that if the warp bubble is moving slowly and is much smaller than the black hole's horizon, it could cause the black hole's entropy to enhance.
However, as they stated in their closing arguments, “there are potentially problematic issues in other physical situations: namely, when a warp drive is completely absorbed by a black hole, its mass and therefore entropy could decrease.
Similarly, when a larger warp bubble passes through the black hole, it creates a “shielding” effect and effectively eliminates the horizon, making it impossible to define the entropy of a black hole in the Hawking sense. If warp drives are possible in nature, these issues indicate that we still do not understand them from a thermodynamic perspective.”
Warp drive technology remains unknown
So while this research could prove valuable theoretically and lead to lab-scale production of mini black holes, many questions remain. Perhaps in the future, once we understand the quantum mechanics behind these two objects, warp technology could prove to be a sure-fire hit.
If so, then we could be dealing with strange time as ships traverse black holes. For example, signals from the interior of a black hole could be carried through a warp bubble connecting to the singularity.
This would allow us to send back images or recordings of what the inside of an event horizon looks like — something no one knows about today. There’s also a chance that these scary black holes could make warp drive easier to achieve, since they wouldn’t need as much exotic “negative energy” source material.
Source: www.universetoday.com
Image Source: Pixabay.com
