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Apr 20 2010 11:11am
Quote (ZvLoD @ Apr 19 2010 03:10am)
If you could travel to a star and back 500 light years away at 99.995% the speed of light, the Earth would be at least 1,000 years older.You would have only aged 10 years.Astronauts time travel frequently. Story Musgrave spent 53.4 days in orbit around the Earth. He was a milisecond younger then he would've been if he stayed on Earth.
If you traveled .01 light years away from Earth and returned at 1% of the speed of light, you would be 8.8 hours younger if they hadn't gone.

To travel backwards in time is all theoretical. You could "somehow" create a wormhole, or find a theoretical cosmic string millions of lightyears across and attempt to snap it back like a rubber band and somehow pass through the ends as they met.
Both of these would require so much energy and mass that they would probably create a black hole, and then you'd still be screwed.


why is this? it would take a little over 1000 years to get there and back, but why would i have aged only 10 years?
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Apr 20 2010 12:06pm
Quote (cletus7seven @ Apr 20 2010 10:11am)
why is this? it would take a little over 1000 years to get there and back, but why would i have aged only 10 years?


From the perspective of say a robot watching you with a telescope on Earth it would take you 1000 years. For you the trip would seem to take only a fraction of the time. Once you were up to a decent speed you would experience length contraction, that is everything would appear shortened in your direction of travel so the star that was 500 light years away wouldn't appear to be that far away. The longest part the journey might be the time it would take you to accelerate to 99.995% light speed and then the time it would take you to accelerate back to "normal speed" at the end of the journey, since if either of these accelerations was too fast you would die.

This post was edited by Azrad on Apr 20 2010 12:07pm
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Apr 20 2010 12:48pm
wow. so the only thing left is to make an engine that can reach the speed of light.

wats the highest speed man has achieved in a machine? isnt it like 23,000 mph.... speed of light is far ahead of that
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Apr 20 2010 04:25pm
Quote (Azrad @ Apr 20 2010 01:06pm)
From the perspective of say a robot watching you with a telescope on Earth it would take you 1000 years. For you the trip would seem to take only a fraction of the time. Once you were up to a decent speed you would experience length contraction, that is everything would appear shortened in your direction of travel so the star that was 500 light years away wouldn't appear to be that far away. The longest part the journey might be the time it would take you to accelerate to 99.995% light speed and then the time it would take you to accelerate back to "normal speed" at the end of the journey, since if either of these accelerations was too fast you would die.


thats pretty crazy. confusing, but awesome. lol.
so basically it is traveling into the future, but it would just take about 10 years to do so. haha
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Apr 20 2010 04:26pm
Quote (juliusjuice @ Apr 20 2010 08:42am)
i think you would indeed end up in a never before explored condition. you would be ripped apart before you knew it and scattered across a whirlpool of the similar. endlessly speeding up toward the center which you will never reach. if there is another side, little or no matter actually reaches the "hole" (or comes out of the 'white hole' on the 'other side'). some theorize the energy that passes through the "hole" is gravity itself, which we dont understand at all.

fathom this: if the entire earth was compacted to equal density of a black hole it would be the size of a thumbnail. the enormous stars that create black holes are much much bigger than the sun. after they expire and collapse (black holes exert much much less energy than the star that they were) they shrink to a size much less than the moon -which is relatively insignificant in size.


wat.
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Apr 20 2010 11:37pm
no1 nos wats up, ppl are just jumping to assumptions like in the old times wen they thought the universe was a trillion miles in diameter, or wen the catholics thought the earth was flat. there isnt a black hole anywhere near us to study and we have ppl making up stuff about it. all we know is that it sends out a strong force of gravity, nothing we know about the insides of it or what happens wen u enter one.
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Apr 20 2010 11:42pm
Quote (Krassen @ Apr 21 2010 05:37am)
no1 nos wats up, ppl are just jumping to assumptions like in the old times wen they thought the universe was a trillion miles in diameter, or wen the catholics thought the earth was flat. there isnt a black hole anywhere near us to study and we have ppl making up stuff about it. all we know is that it sends out a strong force of gravity, nothing we know about the insides of it or what happens wen u enter one.


so you're saying we know the dimensions of the universe?
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Apr 21 2010 07:10am
Quote (BaconLord @ 10 Apr 2010 14:33)
If your future self tells you to alter something in the present, and you do so, would that future self ever have existed to tell you to change something?

Here's the logic:

Future self comes, says change something
You change it
that future self never existed, so it never came
????
Profit?


Experience has tell us that the "logic" doesn't always work in all situations.

You can see Quantum Mechanics and apply your "logic" ( in the sense of "what we see in the macroscopic world everyday" ). Also try to apply that "logic" in a situation when you move at v=c or when you're in a strong gravity field, or when you have rotations of a thing that its behaviour belong to Su(2) group, instead the rotations under SO(3).

Then you will see that the fact that we "see" how the world is, in our daily experience of macroscopic world, doesn't mean that the world is so in all situations; we see a particular case, when density of energy is low, speed of objects is low compared with c, quantum efects are not apreciable and so on.

So trying to follow a "logic" way, when you're considering an anomalous situation, will give a false conclusion.

There are some ideas about closed time curves, and it's possible in theory, but I think we need an advance in the theory/experiments to explain it with precission.

Edit: By the way, travelling to the future is quite easy, it's made by each particle acelerator everyday. Some particles have a known half life time. When you make them move nearly to V=c, their half life time is increased, so they live more than they do = travel to future.

This post was edited by nAc_LOvEs_mArYjAnE on Apr 21 2010 07:14am
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Apr 21 2010 09:42am
Quote (nAc_LOvEs_mArYjAnE @ Apr 21 2010 09:10am)
Experience has tell us that the "logic" doesn't always work in all situations.

You can see Quantum Mechanics and apply your "logic" ( in the sense of "what we see in the macroscopic world everyday" ). Also try to apply that "logic" in a situation when you move at v=c or when you're in a strong gravity field, or when you have rotations of a thing that its behaviour belong to Su(2) group, instead the rotations under SO(3).

Then you will see that the fact that we "see" how the world is, in our daily experience of macroscopic world, doesn't mean that the world is so in all situations; we see a particular case, when density of energy is low, speed of objects is low compared with c, quantum efects are not apreciable and so on.

So trying to follow a "logic" way, when you're considering an anomalous situation, will give a false conclusion.

There are some ideas about closed time curves, and it's possible in theory, but I think we need an advance in the theory/experiments to explain it with precission.

Edit: By the way, travelling to the future is quite easy, it's made by each particle acelerator everyday. Some particles have a known half life time. When you make them move nearly to V=c, their half life time is increased, so they live more than they do = travel to future.



not the kind of "traveling to the future" we had in mind all along
:D

people think wormholes and different universes like how they do it in the movies, in reality its a lot different.
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May 10 2010 07:29pm
id time travel and go SOISOISOI ROFL COPTER
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