Spacetime would therefore also be curved inside the bubble. To travelers in a spaceship right in the middle of the bubble, this phenomenon would be most obvious in the passage of time: their watches would go slower than in the rest of space because, according to the theory of relativity, time is affected by gravity. The slower passage of time on a spaceship might be something interstellar travelers appreciate.
Still, Bobrick and Martire describe other obstacles. So far, they argue, there is no known way to actually accelerate a warp bubble.
All previous ideas about the subject simply assume that the curvature of spacetime is already moving at high speed. A beam of light travels , kilometers per second. The speed of light is the maximum speed any particle may reach, and a particle can only do so if it has no mass. On closer inspection, however, this limit only applies within the four-dimensional spacetime comprising the universe. Outside of that, even greater speeds appear to be possible. That is because you would require matter capable of being ejected at speeds faster than light—but no known particles can travel that fast.
Furthermore, the bubble could not be controlled by occupants of the spaceship itself because they would lose contact with the outside world, owing to the extremely strong curvature of space around them. Lentz sees these objections as a problem, too, but he believes a solution can be found. Bobrick, meanwhile, points out that it is also possible to travel to distant stars at a third or half the speed of light, especially if time passes more slowly for the people in the warp bubble.
Just do not think about the fact that all your relatives left behind on Earth will probably have died of old age before you get back. There is still some debate about whether warp bubbles really can do without negative energy.
Recently, three theoreticians suggested that this claim was only true for observers moving next to the bubble. Plus, not everything that seems possible according to the theory of relativity actually exists—or is technologically feasible. That could be because laws of nature, as yet unknown, preclude such phenomena. Some researchers therefore caution against going overboard with the fantasies. Space propulsion expert Martin Tajmar of the Technical University of Dresden, for example, sees no practical relevance for the current work on warp drives.
The huge masses involved simply exceed anything that can be tested on Earth, he says. Most veteran warp drive researchers would undoubtedly agree. They see their work less as preparation for real-world experiments and more as a way of exploring the limits of relativity. Lentz, on the other hand, is actively working toward a practical application of his idea. But in his spare time, he still thinks about how to accelerate a bend in spacetime to speeds faster than light and how to reduce the energy required to do so.
Lentz also advocates looking closely at the surroundings of neutron stars. It could be that these ultracompact stellar remnants eject bubbles like those that he describes in his paper. The ship was pushed swiftly to another distant destination. Physics has scoffed at the idea of a real warp drive because it suggests travel faster than light.
However, as the drive's name suggests, such an engine did not push the spacecraft faster than the speed of light; instead, it merely warped space-time in a way that allowed for using a shortcut. But, the new study has a workaround. According to researches from the independent research group Applied Physics based in New York, it is possible to ditch the fiction of negative energy and still make a warp drive, albeit one that is slower than in "Star Trek," ScienceAlert reports.
Lentz proposes that conventional energy sources could be capable of arranging the structure of space—time in the form of a soliton — a robust singular wave. Unlike objects within space—time, space—time itself can bend, expand or warp at any speed.
He adds that to be practical, this requirement would have to be reduced by about 30 orders of magnitude to be on par with the output of a modern nuclear fission reactor. Lentz is currently exploring existing energy-saving schemes to see if the energy required can be reduced to a practical level. Any warp drive would also need to overcome several other serious issues. Lentz describes his calculations in Classical and Quantum Gravity , where other recent research on the topic is outlined in an accepted manuscript from Advanced Propulsion Laboratory researchers Alexey Bobrick and Gianni Martire.
Though he recognizes these huge hurdles to building a warp drive, Lentz feels they are not insurmountable. Science fiction writers have solved this dilemma by inventing the warp drive, a gadget that magically propels ships across the vast expanses of the solar system faster than the speed of light.
Travelling faster than the speed of light continues to capture the imagination of many scientists, who believe bending the laws of physics may allow us to break the universal speed limit.
Several theories have been proposed, including the Alcubierre warp drive theory. Instead of trying to beat the speed of light, which is physically impossible, the Alcubierre warp drive would go around it by warping space-time itself, Star Trek style!
According to the theory, the travelling spaceship would sit within a warp bubble surrounded by a ring of negative mass. This would enable you to shrink space-time in front of the spaceship and stretch space-time behind it, enabling it to travel through space at ten times the speed of light.
While inside the bubble, the craft would remain within the universal speed limit and general relativity would remain intact. There is only one small issue - it would need enormous mass energy to make the warp drive work. To propel the spaceship at this speed you would need the mass equivalent of Jupiter, the planet!
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