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After looking at the current discovery of Higgs Boson and the next long term plans of NASA and ESA(European Space Agency), I can't stop myself asking about the possibilities in near future.

According to my little knowledge, time travel is possible if we can bend the space-time fabric. The bending or curving of space-time fabric is possible only by black hole or worm hole(Although I don't know the specific difference between these two). Now to think about black hole which is a gravitational sink of the universe which has infinite mass where masses sink and on the other side the black hole there is white hole which is big bang. So this seems the game of gravity.

But to really get any clue any information about gravity of cosmic objects, the so called gravitational waves are the medium. To get all the information about presence of black-hole NASA and ESA are planning for the project LISA which will detect the gravitational waves from distant cosmic objects.

I would happy to know from theoretical physicists that how far the project LISA can help in this direction. If anybody can share their view about this and can throw some light on possibility of time travel, I would be grateful.

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closed as too localized by Qmechanic, Sklivvz, Manishearth Dec 29 '12 at 15:59

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why there is a negative vote to my question? –  Surjya Narayana Padhi Aug 20 '12 at 3:36
While I do not know who downvoted your question and why, my guess is that you have not presented any reason that you would expect LISA to help advance the possibility of time travel, and that your question demonstrates significant misconceptions about the underlying physics. –  David Z Aug 20 '12 at 17:09
I put this as a question but not a suggestion. My assumptions may be wrong. That's why I am clarifying. But down voting this question is embarrassing. I know there is some hidden reason behind down voting this question. –  Surjya Narayana Padhi Aug 21 '12 at 6:28
By the way these assumptions I got from Dr.Michio Kaku. He has explained about extra-dimensions and project LISA. So in that context with curiosity I asked this question. –  Surjya Narayana Padhi Aug 21 '12 at 6:30
Well, all I can say is that somewhere between Dr. Kaku's knowledge of physics and the wording of this question, some facts got mixed up. If you had asked for clarification on the meaning of what he said, perhaps that question would have been better received, but in this case it seems like you've misinterpreted some things and taken those misinterpretations to be true, which is the sort of thing people tend to downvote for. –  David Z Aug 21 '12 at 8:46

1 Answer 1

LISA does nothing to advance time travel.

Your question seems to be based on some incorrect assumptions. For example:

The bending or curving of space-time fabric is possible only by black hole or worm hole

Actually not, spacetime "bends" or curves whenever there is mass. The curvature is most extreme near a black hole or wormhole, but even around the Earth, there is a very slight spacetime curvature.

black hole which is a gravitational sink of the universe which has infinite mass

Black holes don't have infinite mass. The singularity predicted by GR has infinite density, that's all.

time travel is possible if we can bend the space-time fabric

Yes, but it takes a very particular kind of bending, beyond what can be caused by a black hole and of a sort that is unlikely to arise in nature, if it is even possible. Specifically, time travel via spacetime trajectories, or closed timelike loops as they are called, requires particular topological properties of spacetime, in addition to the local geometric properties specified by GR.

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I wouldn't associate a density to the singularity, whether timelike or spacelike. I don't know what it means to say the singularity is infinitely dense. –  Ron Maimon Aug 20 '12 at 5:00
Yeah, I could agree with that. Honestly, my belief is that the singularity doesn't really exist anyway because quantum gravity takes over at some point. But GR does tell us there is a region of zero volume which all mass that enters the black hole does approach, which tends to suggest infinite density. I mentioned it because of the OP's statement about infinite mass. –  David Z Aug 20 '12 at 17:05

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