time travel

[toolman]

Hi,

Im new to this time travel stuff and wondered, if someone went back in time, would they see themselves living in that time or would they become part of that time again?

[TimeTraveler]

Time travel is a hypothetical situation, it cannot really be proven, theoretically it is possible, but there are many answers that are unknown, and the answer you are looking for is also unknown.

[toolman]

Ok thanks. Becuase i was thinking that when someone dies, if they were sent into space and somehow travelled back in time, eg through a wormhole, then they could re-live their life. i know its a wacky story, but i was just wondering it.

[granDODyssey]

if you just wish to explore the possibilities....

{going backward in time}

let's say you are looking at a star 100 light years afar from earth, (obviously it means the light from that star took 100 years to reach us...and the image we see now is 100 years old archive.....because nothing could travel faster than "light" including "time" itself) and if you somehow manage to get there within 1 second , (you not only beat the fastest traveller in the universe by a 100 yr - 1 sec) but also travel (100 yr - 1 sec) back in time.

(e.g imagine "you" and "light" compete in painting a picture of the star, "you" finish it in 1 sec but "light" only finish a very small fraction of what you have done....that means you got to wait about 100 years to see "light"'s finishing touch on the picture....in other word, you have travelled into past of "light"....!! )

 

so ...if you imagine yourself as a 100 yrs old...and want to see yourself being born....you could travel to that star with the same speed you did before for 1/2 sec and return back to earth for another 1/2 sec....i think you could see yourself crying in the labor room.... ....(just letting myself thinking wild.)

[ed84c]

that requirs travelling faster than light though, and technically in asyptiomatically flat space time you havent travelled through time. You could easily go into the future by putting yourslef somewhere very dense where time slows.

[granDODyssey]

that's true...i think...travelling forward in time is much easier a concept than the backward....you just need your relative time to slow it down....like if you could encircle the earth by 6-7 times in a second, you could slow your body timer to a snail's pace than that of the earth's timer....and when you finally decide to land on the earth ...you will found yourself as in "Back to the future V" or something...

[mak10]

that's true...i think...travelling forward in time is much easier a concept than the backward....you just need your relative time to slow it down....like if you could encircle the earth by 6-7 times in a second, you could slow your body timer to a snail's pace than that of the earth's timer....and when you finally decide to land on the earth ...you will found yourself as in "Back to the future V" or something...

 

I will admit, time-travel is one concept that I have trouble understanding. If you encircle the earth 6 or 7 times per second... you have merely crossed the circumference of the earth 7 times in 1 second... how, on earth, then, does it affect your body's biology... like stop you from aging and stuff?? I also profess ignorance about einstein's relativity theories which maybe related to time-travel and all that stuff!

 

My argument is that 1 second travelling at light speed is still 1 sec anywhere else in the universe... the time interval remains the same. Its just the distance you have covered in that 1 sec as a result of your speed that differs from the distance the snail has covered on earth for the same time interval. This is as how I see it.... but then again, i might be thinking solely in terms of newtonian mechanics, to what I have been taught as of yet.... but I would appreciate a good explanation of this phenomenon. Thanks!

 

-mak10

[SubJunk]

basically, according to Einstein, light and time are intertwined. If we were to travel to half the speed of light for instance, one second to us would be two seconds to other people. various other things happen, such as your physical length shrinking to half its size (length in the direction you're travelling i mean) and gaining mass. It's a lot more complicated obviously but that's the basics.

If I've explained this incorrectly I apoligise as I just woke up

[mak10]

basically, according to Einstein, light and time are intertwined.

 

has this been experimentally verified?

 

-mak10

[alt_f13]

Mathematically, yes.

 

[edit]

 

And yes, when an atomic clock was launched into space, just the relatively low speed by which it travelled actually let it experience time at a "faster" pace than we did here. When it arrived back, it was several milliseconds "in the future" by its own viewpoint (ie, milliseconds ahead to us).

[Geode]

MAk10 wrote: has this been experimentally verified?

 

Experimentally, as noted. Empirically, as well. Certain particles with an established decay rate coming from the sun (if memory serves) are detectable by sensors on the ground, when they should have decayed before reaching the ground.

 

 

Geode

[mak10]

can I have some authoritative links where I can read about these?? thanks!

 

-mak10

[SubJunk]

go here http://www.physics.northwestern.edu/classes/2004Spring/Phyx103/einstein.html you'll find some interesting stuff

[ooptydoo]

if u really interested u should come visit me.

some parts of this town r in ur future.

hard to tell appart

once we meet theres no turning back

but we could have some fun>

[ydoaPs]

if u really interested u should come visit me.

some parts of this town r in ur future.

hard to tell appart

once we meet theres no turning back

but we could have some fun>

 

One would think that any self-respecting time-traveler would not only be capable of using spell-check, but would also have a more consistent use of punctuation and would refrain from txt-spk.

[KtownChemist]

The idea of traveling back in time is as impossible as negative distance. No matter where you stand any way you move is positive distance, and if you move five feet forward and five feet back you have still moved 10 feet not 0.

[Kyrisch]

One would think that any self-respecting time-traveler would not only be capable of using spell-check, but would also have a more consistent use of punctuation and would refrain from txt-spk.

 

Don't you get it? That's all that's left of the english language in the future! We all knew it was going to happen....

[swaha]

if u travel faster than light may be u actually go to ur past but can anybody explain what to see then? for by lorentz transformations you get an imaginary length.