Future spaceships can use black holes like powerful launcher pads to explore the stars.
A new study predicts shooting laser beams that would bypass around a black hole and come back with extra energy to help propel a spaceship to close the speed of light. Astronomers could look for signs that foreign cultures are using such a "halo journey," as his study has done, by that pairs of black holes merge more often than expected.
The author of the study, David Kiping, an astrophysicist at Columbia University in New York, raised the idea of the aura journey through what he calls the "gamer's mood."
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"Sometimes, in a computer game you find" exploit ", an ax that allows you to do something overweded that otherwise would have been prohibited by the rules of the game," Kipping Space.com said. "In this case, the game is the physical world, and I tried to think of an abuse that would allow civilization to get relational flight back and forth across the galaxy without the enormous energy expenditure that can be assumed innocently."
A key challenge to using rockets to fly in this space The impulse they carry with them There is mass. Long trips require a lot of flammability, making the rockets heavy, which in turn requires more propellant, making the rockets even heavier, and so on. This problem is getting worse and worse.
Instead of carrying an impulse for propulsion, however, a spaceship equipped with mirror-like sails can rely on lasers to push them out. 100 million dollars Breakthrough, Announced in 2016, plans to use powerful lasers to propel swarms of the Alpha Centauri spaceship, our closest star system, at up to 20 percent the speed of light.
The spacecraft that the Starshot breakthrough aims to launch are all just about the size of the chip. To speed up larger spaceships to relative velocities – to a significant fraction of the speed of light – Kiping was looking for gravity.
The spacecraft regularly uses "slingshot exercises," in which the gravity of a body, such as a planet or moon, throws space vessels on the surface and increases their speed. In 1963, famous physicist Freeman Dyson suggested that spacecraft of any given size would rely on ballistic maneuvers around compact pairs of white dwarfs or neutron stars to fly at relativistic speeds. (Dyson came up with the idea of what became known as a Dyson Ball, A large structure orbiting a star to capture as much energy as possible to propel an advanced civilization.)
However, the "Dyson zipper" risked hitting a spaceship using extreme gravitational forces and dangerous radiation from those pairs of dead stars. Instead, Kiping indicates that the gravitational force may aid the spacecraft by increasing the energy of laser beams fired at the edges of the black holes.
Black holes have gravitational fields so strong that nothing can escape them as soon as it gets close enough, not even easy. Their gravitational fields can also distort the photon paths of light that do not fall into the holes.
In 1993, physicist Mark Stuckey suggested that a black hole could, in principle, act as a "gravitational mirror," that the gravitational force of the black hole might cast a photon around it, so that it would return to its source. Kiping calculated that if a black hole moves toward a photon source, a "photon boomerang" will pour some of the black hole energy.
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Using what he called a "halo drive" – in the name of the ring of light, it was created around a black hole – Kiping found that even spaceships with the masses of Jupiter could achieve relativistic speeds. "A civilization can use black holes as galactic access points," he wrote Research Accepted by the Journal of the British Interstellar Company Detailed Web February 28 on arxiv preprint server.
The faster the black hole moves, the more energy a halo drive can draw from it. As such, kiping has focused primarily on the use of pairs of black holes twisting towards each other before the merger.
Astronomers could look for signs that foreign civilizations are exploiting pairs of black holes for such a motor. For example, halo drives will steal such energy efficiently Binary Systems Black Hole, Increasing the rates at which pairs of black holes merge over what one would expect to see naturally, Kiping said.
His findings were based on strengthening pairs of black holes that orbit each other at relative speeds. Although there are about 10 million pairs of black holes in the Milky Way, Kiping noted that few of these are reasonable at relativistic speeds over time, as they will merge fairly quickly.
However, he noted that individual rotating black holes can also motivate halo drives at relative speeds, "and we already know of many examples of supermassive black holes."
The main drawback of the drive halo would be that "one should drive to the nearest black hole," Kiping said. "It's like paying a one-time toll fee to ride on the road system, you have to pay some energy to get to the nearest access point, but after that, you can ride for free as long as you like."
The halo drive operates only near a black hole, about 5 to 50 times the diameter of the black hole. "That's why you have to travel to the nearest black hole first [why you] Can not just do it over the light years of space, "Kiping said," We still first require means to travel to the nearby stars to ride the road system.
"If we want to achieve relational flight, it takes enormous energy levels no matter which propulsion system you use," he added. "One way to get around this is to use astronomical objects as your source of power, since they hold verbally Astronomical levels of energy with them. In this case, the binary black hole is actually a huge battery waiting for us to tap on it. The idea is to work with nature and not against it. "
Kiping is now examining ways to utilize other astronomical systems for relativistic flight. Such techniques "may not be as efficient or as fast as a halo drive approach, but these systems hold deep energy reserves necessary for these journeys," Kiping said.