"Time Travel"

[Afrobean]

Re: "Time Travel"

Why does it "stand to reason" that light which reflected off earth a long time ago captured and maintained an image of the earth at the time of reflection? I certainly don't have near enough an understanding of optics to say that with any kind of certainty. Do you?

Your contention is whether the light would be able to carry the image that far without dilution?

If our telescopes are picking up old light off of stars and giving us a good picture of it, is it really that big of a stretch to imagine that the same process could be used with better technology to a planet from a similar distance?

And yeah, this is all really just a simple question: if it were possible (which it certainly isn't), would the same idea hold true? I submit that it certainly would, but anything you could see in this manner would be essentially useless.

But if we could TRAVEL TO THE ENDS OF THE UNIVERSE faster than the speed of light, could we SEE THE BEGINNING OF TIMEEEEEEEEEEEEEEE?

[ShAiOnEi]

Re: "Time Travel"

There is no way time travel could be executed unless you could find a way of manipulating space and time. As of seeing our selves in the past due to light travel speeds I find this a very hard task to do.

[devonin]

Re: "Time Travel"

Your contention is whether the light would be able to carry the image that far without dilution?

My contention is whether the light "carries" the image at all in that kind of meaningful sense.

The impression I'm getting from the way this process is being described is like, "Light hits the planet, is reflected off, and goes out into the depths of space, and we're going to go supre fast past it, turn around and look at it!" I don't really see how that will let us see much of anything except "some light" even assuming we pretend that there's no diffusion at all.

I'm presumably just missing something integral in the process here. Do I assume instead that we're just going really far away and then looking at the actual physical location of the planet, and somehow will be seeing it earlier in its history because we went away faster than light? Even assuming we also corrected for the fact that Earth won't exactly be where we left it either.

[Heartseeker7]

Re: "Time Travel"

But if we could TRAVEL TO THE ENDS OF THE UNIVERSE faster than the speed of light, could we SEE THE BEGINNING OF TIMEEEEEEEEEEEEEEE?

This brings in a whole different topic of whether the universe goes on forever, or if it ends at a certain point. I personally would rather see whats on the other side of the "ends of the universe" then the beginning of time.

[John McPain]

Re: "Time Travel"

This brings in a whole different topic of whether the universe goes on forever, or if it ends at a certain point. I personally would rather see whats on the other side of the "ends of the universe" then the beginning of time.

I would rather keep the discussion on topic please?

obviously if light travels in a straight line forever

I know it doesen't help my case at all but light does not alwase travel in a straight line. Light can be bent from gravity and magnitism.
Source = http://van.physics.uiuc.edu/qa/listing.php?id=1170

[devonin]

Re: "Time Travel"

I suppose we also have toa ccount for the whole "Light can act as a particle and as a wave" thing. It seems like light as a wave would be the best source of the clear view you're supposing we might have, if simply because light as particles seems like it would be more susceptible to gravity and magnetism causing problems.

[John McPain]

Re: "Time Travel"

I suppose we also have toa ccount for the whole "Light can act as a particle and as a wave" thing. It seems like light as a wave would be the best source of the clear view you're supposing we might have, if simply because light as particles seems like it would be more susceptible to gravity and magnetism causing problems.

I agree but aren't waves also susceptible to unwanted abberation through differing mediums?

[MDMAngel]

Re: "Time Travel"

The reason why we are able to see light from millions of years ago is because that's how long it took to travel from its source to the Earth.

~Tsugomaru

Note: I didn't read every post, just up until this one.

I agree with that...

The only thing we are looking into the 'past' of is the present of what's up for the future, which makes it seem like the past... but time has not been distorted in any way.

Light doesn't travel through time, I believe. It's just a matter of the length of time it takes something to reach one place to another, in a revealing pattern.

Even if we could see into the past, there's no such thing as altering it...

If you could, altering the past, even just a TINY bit... it could cause devastating results worldwide... or could change for the better, but more likely would not. What is done is done.

[8Shade8]

Re: "Time Travel"

Here is a theory/question: Would you be able to see different parts of the past based on how you focused your telescope? The fourth dimension is too complex for us to contemplate and play with right now, but under the circumstances that we somehow had the technology to travel faster than the speed of light, and made it light years away from earth and then aimed a telescope at earth, or even our solar system, it would make sense that you could instantly watch hundreds of thousands of years go by, simply by adjusting the focus on your telescope. Zooming in would fast forward time and slowly zooming out would rewind time. Sounds fun right?

[devonin]

Re: "Time Travel"

From my understanding of time, objective time is objective time. Your subjective time runs at a different speed as your speed approaches and even though we think it can't be done, surpasses the speed of light.

What would have to happen, it seems to me, is that if you moved away from the earth at almost the speed of light, when you stopped, and "fell back into" objective time, it would be the case that X years had passed for you, and a number >X years would pass for everything else. That would technically be time travel into the future because you spent say 1 year in travel and the earth has gone and "aged" 50 years. If you were to look at the earth, you would see earth as it "is now" but because of the relativistic effects of near-lightspeed travel, you would see it seeming subjectively older.

It would follow, to me, that if faster than light travel -were- possible, that yes, you would technically be going "back" in time, but again, once you "fell into" normal objective timespace again, you'd still only see the earth as it "is now" but because of the relativistic effects of greater than lightspeed travel, you would see it seeming subjectively younger.

I still don't buy the idea that you could look physically at the light which has already reflected off the Earth and gone very far away just by catching up to it super fast, and still see anything at all except "some light, quite diffused, coming from thataway" The only way you could see Earth, it seems to me, would be to look at Earth, and you'd only see it as it was "at the time" you looked. No movie versions of Earth's development, you'd have to travel around more at either more than lightspeed to go backwards, or less than lightspeed to go forwards.

[slipstrike0159]

Re: "Time Travel"

All of this is, for the most part, just an idea because we wouldnt be able to test it out. However ill pose the question again, why does it matter what would happen? It would not be worth all of this effort to 'fly through space going super fast and look back' only to see earth at an earlier state (assuming it worked) unless you could watch life as it starts and develops. Even getting to this impossible point where we got past the old light to tack on the ability to have a telescope that could see microscopic cells and organisms grow would be too much. Even seeing pangea would give us what, very little information at most? The information that we would be able to learn would be not very usefull especially if you figure that once we get this technology we would have advanced to the point where we could figure it out without such a process anyway. Sorry if it seems like im ranting, but i just realized the pointlessness of it all.

Anyway, 'time travel' in the traditional media sense would suggest being able to do or see something in the past/future we didnt already know. This would then bring the point of if you did/saw something remarkable, would it alter anything or would everything stay the same because it was 'supposed' to happen. The biggest problem i have with time travel in the media sense is that if someone years in the future found out how to achieve something like this and the 'butterfly effect' came into to play then from the moment the technology was discovered until the end of time there would be infinite chances for something to go wrong. The worst of which being a catastrophy that ends the world for which all of us now would see as it unfolds thus making 'our' ability to get this technology unavailable or at the very least useless.

[devonin]

Re: "Time Travel"

Or we're just already living the reality that is the result of all current and future trips into our past.

[Loverofstories]

Re: "Time Travel"

Or we're just already living the reality that is the result of all current and future trips into our past.

"Reality is an illusion. Albeit a very persistent one."
-opinion from a scientist (albert einstein ). Try non-sense. What currently see: stars AS they have shone millions of years ago (from another place made of many small images - if you have uber powerful telescopes you can see them as they are now).

[Afrobean]

Re: "Time Travel"

"Reality is an illusion. Albeit a very persistent one."
-opinion from a scientist (albert einstein ). Try non-sense. What currently see: stars AS they have shone millions of years ago (from another place made of many small images - if you have uber powerful telescopes you can see them as they are now).

You have a telescope that can increase the speed of light to be superluminal speeds? How does that work? Also, how does it speed up the light that is still many light years away? I might be able to believe in a telescope which can increase the speed of the light within it, but how can a telescope speed up light which is far away from it?

[Sol_Solis]

Re: "Time Travel"

You have a telescope that can increase the speed of light to be superluminal speeds? How does that work? Also, how does it speed up the light that is still many light years away? I might be able to believe in a telescope which can increase the speed of the light within it, but how can a telescope speed up light which is far away from it?

Umm, as they appeared* - i think thats the correct tense.
Telescope uses curved mirrors! It does wonders, picture hubble as the most powerful with more mirrors and groovy technical things. If I could remember I could handle a more eloquent explanation, but basically you start with a curved mirror, light, and go from there (the light reaches the curved shape and the image becomes intensified and focuses it into a single one - how seemingly simple, we managed to get one IN OUTER SPACE!!!). It has more advanced operation features however, so now one can't say.

http://science.howstuffworks.com/telescope1.htm