Time Travel?

steeze4days

steeze4days

Member
Right, so this has been bothering my for the past half an hour or so, as you should know, light travels at a certain speed, and so (assuming Extraterestrial life is out there) if an "alien" were to look at earth through a telescope from far enough away, they/it may for example see dinasours roaming the earth, or just an empty planet due to the the fact that the present light being reflected off of earths surface must still travel for a long time through space before it reaches this "Alien" (all normal so far right?)

Now, assuming this alien jumps in his theoretical space ship and begins to fly towards earth at great speed, surely he would be traveling through time? As the alien would be observing the more recent light being reflected from earth and so he would be watching earth go from past to present faster than it really has?

And so I just wrote this all for no reason as I now remember that you (theoretically) can not surpass the speed of light. And so it would take the alien the amount of time to get to earth and see that there are now humans on it as it would between dinosaurs inhabiting the earth and humans developing civilisation. Fuck.

Ok bye.

(No I didn't take lsd)
 
16ad3ie.gif
 
This would be true if one does not factor in the theory of relativity.

That's all I got.
 
So if you think about it if you have a telescope on a space ship that hauls ass faster than light and it is zoomed in on earth would you be seeing like a time lapse starting from dinosaurs to present time. if that makes sense
 
13408640:dingus said:
So if you think about it if you have a telescope on a space ship that hauls ass faster than light and it is zoomed in on earth would you be seeing like a time lapse starting from dinosaurs to present time. if that makes sense
Click to expand...

Vsauce did something on the subject.

 
fuck I just thought I had a good response but then I realized it made no scense. Damn this is all I'm gunna be focusing on for the next 3 days
 
13408640:dingus said:
So if you think about it if you have a telescope on a space ship that hauls ass faster than light and it is zoomed in on earth would you be seeing like a time lapse starting from dinosaurs to present time. if that makes sense
Click to expand...

yeah
 
So everything would be in extreme fast forward? kind of like the doppler effect, but with light? very curious indeed!
 
Ok so I've thought about this a lot and have come to this conclusion: as particle physics suggests, the alien would indeed see earth from say, a million light years away. Now if the alien traveled at the speed of light while watching the earth, they would see the earth transform, see the bomb being dropped on Hiroshima and Nagasaki, etc. The alien would not be time traveling, as all they are seeing in the telescope is a "recording" of history. I think we need Keefer to weigh in on this. He is after all a philosopher/astrophysicist.
 
Essentially it wouldn't be time travel due to the fact it is impossible to travel faster than the speed of light. Hypothetically though, if the alien were to view the earth from his X light distance away, he would be viewing the earth as X amount of years older than present day.

13408640:dingus said:
So if you think about it if you have a telescope on a space ship that hauls ass faster than light and it is zoomed in on earth would you be seeing like a time lapse starting from dinosaurs to present time. if that makes sense
Click to expand...

You know those old Microsoft screensavers with the Stars flying towards the screen? It would be something like that. Assuming you could travel faster than light. (Knowing we can't) You wouldn't be able to view anything from the telescope on-board the ship as you know were traveking faster than light, and that's what makes all things visible, the reflection of light off an object. "Old light" (hypothetical) would be passing by you and essentially nothing would be visible.
 
13409444:ck0belski said:
Ok so I've thought about this a lot and have come to this conclusion: as particle physics suggests, the alien would indeed see earth from say, a million light years away. Now if the alien traveled at the speed of light while watching the earth, they would see the earth transform, see the bomb being dropped on Hiroshima and Nagasaki, etc. The alien would not be time traveling, as all they are seeing in the telescope is a "recording" of history. I think we need Keefer to weigh in on this. He is after all a philosopher/astrophysicist.
Click to expand...

Would be cool to see a timelapse of earth
 
This is off wiki but it is a pretty good explanation.

Some theories, most notably special and general relativity, suggest that suitable geometries of spacetime or specific types of motion in space might allow time travel into the past and future if these geometries or motions were possible.[24] In technical papers, physicists generally avoid the commonplace language of "moving" or "traveling" through time ("movement" normally refers only to a change in spatial position as the time coordinate is varied), and instead discuss the possibility of closed timelike curves, which are worldlines that form closed loops in spacetime, allowing objects to return to their own past. There are known to be solutions to the equations of general relativity that describe spacetimes which contain closed timelike curves (such as Gödel spacetime), but the physical plausibility of these solutions is uncertain.

Relativity predicts that if one were to move away from the Earth at relativistic velocities and return, more time would have passed on Earth than for the traveler, so in this sense it is accepted that relativity allows "travel into the future" (according to relativity there is no single objective answer to how much time has really passed between the departure and the return, but there is an objective answer to how much proper time has been experienced by both the Earth and the traveler, i.e., how much each has aged; see twin paradox). On the other hand, many in the scientific community believe that backward time travel is highly unlikely. Any theory that would allow time travel would introduce potential problems of causality. The classic example of a problem involving causality is the "grandfather paradox": what if one were to go back in time and kill one's own grandfather before one's father was conceived? But some scientists believe that paradoxes can be avoided, by appealing either to the Novikov self-consistency principle or to the notion of branching parallel universes (Time Travel).

So I don't get in trouble

"Time Travel." Wikipedia. Wikimedia Foundation, n.d. Web. 24 Apr. 2015.
 
13409287:shotvet said:
So everything would be in extreme fast forward? kind of like the doppler effect, but with light? very curious indeed!
Click to expand...

Doppler effect does occur with light. Its evidence for universal expansion. Look up Hubble's law.
 
Alien would be seeing shit faster than usual

Think of a giant hose up in the sky, dropping water down below in a steady steam. The hose drops every second, so the water is hitting the ground at a rate of approx.

(for each "-" represents a quarter second)

Drop - - - - Drop - - - - Drop - - - - Drop - - - - (4 seconds)

Now, lets say you are flying up towards the hose in the sky at a rate of speed that makes the periods between the drops a half second. The water would be like

Drop - - Drop - - Drop - - Drop - - Drop - - Drop - - Drop - - Drop - - (4 seconds)

So, in 4 seconds, you would be seeing more water drops in the same amount of time. Same with our alien.

It's not time travel, you aren't hitting drops from the future, your just hitting drops closer to the hose, meaning in perspective to our alien, closer to earths current time.

 
You must log in or register to reply here.
Back
Top