Can anyone explain to me?? please

[Peron]

I'm having trouble understanding how the Krasnikov Tube works.http://en.wikipedia.org/wiki/Krasnikov_tube

 

Is it a time machine? Is it only a F.T.L drive relative to the crew that departs Earth?

[ajb]

This paper maybe of help

 

A Superluminal Subway: The Krasnikov Tube

Authors: Allen E. Everett, Thomas A. Roman

Journal reference: Phys.Rev. D56 (1997) 2100-2108

arXiv:gr-qc/9702049v1

 

It is possible to use two spatially separated Krasnikov tubes to create a time machine. This is also the case with worm holes and other bubble-warp drive scenarios.

Edited March 24, 2010 by ajb

[Icefire]

For example, suppose that a tube is built connecting Earth to a star 3000 light years away. The astronauts are traveling at relativistic velocities, so that the journey only takes 1.5 years from their perspective. Then the astronauts lay down tube II rather than traveling back in tube I, the first tube they produced. In another 1.5 years of ship time they will arrive back on Earth, but at a time 6000 years in the future of their departure. But now that two Krasnikov tubes are in place, astronauts from the future can travel to Deneb in tube II, then to Earth in tube I and will arrive 6000 years earlier than their departure. The Krasnikov tube system has become a time machine.

From what I gather it will allow you to travel to a different location while you experience time at a accelerated (or decelerated idk) rate (eg: it takes you 22 hours to fly to australia, but you experience it as five minutes). Returning is something that's a lot harder for me to wrap my head around.

Observe:

Normally you would live on earth for about 60 years, represented by the blue line.

Now suppose you took a K-Tube that brought you to a far away destination at a very fast velocity. To anybody tracking you, you will take 30 years to arrive there, but you will experience those 30 years as a week or so. then you get there, and do your stuff.

When you want to go home, you have to options:

1. you take the tube that brought you there. it maintains the same location in time and space (but presumably the entrance/exit continue to exist), which means that when you take it you will be going BACK 30 years, according to somebody that is tracking you (presumably you will experience a week, or a negative week), and you will arrive at the same point in time and space as you started (but I believe there will be a difference identical to your stay elsewhere).

2. you take a new tube. same thing as traveling elsewhere. you will arrive at earth 30 years later, for a grand total of 60 years plus the time you spent elsewhere in reality, but you experience only two weeks plus the time that your were elsewhere.

Actually, I don't know. the more I think about it the less sense it is, and the bigger my headache.

[Peron]

Okay, so if I want to launch a Krasnikov type mission to a globular star cluster 25,000 light years away. The people on Earth still have to wait 25,000 years before the spaceship can get there? Or since the krasnikov tube is a tunnel through time, then as soon as the ship leaves, the ship comes back with out the people on Earth having to have to wait?

[Sharapovaphan]

This paper maybe of help

 

A Superluminal Subway: The Krasnikov Tube

Authors: Allen E. Everett, Thomas A. Roman

Journal reference: Phys.Rev. D56 (1997) 2100-2108

arXiv:gr-qc/9702049v1

 

It is possible to use two spatially separated Krasnikov tubes to create a time machine. This is also the case with worm holes and other bubble-warp drive scenarios.

 

What happens to time in a warp drive? I mean you can cheat space, we've been doing that forever. We call it a shortcut. Interestingly enough, one takes a shortcut to save time. However classical time (man made time) and the space you occupy on the planet are independent of one another. Quantum time (oxymoron on so many different levels, while simultaneously defining), on the other hand, is "stitched" into the "fabric" of everything (space). Theoretically, a warp drive allows you to reach your destination sooner than you could at the speed of light, and unlike FTL speed, you would be there when you get there. However, what happens to time? You can't cheat time. Doesn't this restrict warp drives to sub light effectiveness? Unless of course electron neutrinos, ghosts, turn out to be tachyon in nature...