You know how when we look into space, we are looking at what happend millions of years ago.?

Question

Like what we look at, is not present.
Anyways, do you think this could have anything to do with time travel, just hypothetically.
Do you think time travel has anything to do with this?

*COULD HAVE anything to do with this

the reason why i think so is because like labsci's answer, you could travel at the speed of light and look back at yourself from 3 hrs ago, and i think that's extremely interesting i want to know more!

Answer 1

In a way, yes, as you are looking back in time to those stars, and the Moon, a few seconds, etc. If, in theory, you could move instantaneously to a point three light hours away, and look back at the Earth, you would see yourself from three hours ago, but could not interact, of course, just look.

Answer 2

Some stars are 10 billion light years away. Other stars are just over 4 light years away.

No, this has nothing to do with time travel. It is merely the time that it takes light to travel these distances to reach our eyes.

--labsci's answer, while entertaining, is not factual. Let's use the 3 hour example. It does not have to be light waves. It can be any type of radio wave or any other signal. If someone yells out to me a mile away, and I hear the sound they made 4.8 seconds later does that now mean that I have travelled through time 4.8 seconds into the past? No. It is only true that now I have heard something that was spoken 4.8 seconds ago. The same is true no matter the medium. If I see a light that was emitted 4.8 seconds ago from 892,800 miles away does that mean that now I have travelled into the past by 4.8 seconds? No.

Now if you are seeking science fiction answers, then by all means let's travel instantaneously. Let's make a virtual clone of ourselves and be in two places at once. One can be in the future and one in the past. Or let's forget physics and build a ship that can travel as fast or faster than light speed. We can come up with all sorts of fictitional scenarios.

If you are seeking an answer with real science fact and information, watching the light from a source that was transmitted 4.8 seconds ago or one million light years ago has nothing to do with time travel.

Answer 3

Arrgghhh, time DOES exist! Why do people keep saying that it doesn't? If time isn't real, then WHAT SEPARATES EVENTS!? Time is as real as length, width, and depth. Oh, are you going to argue now that length isn't real because it's just our perception of how far apart two points are? Baloney!

Now, to answer your question...

The reason we see into the past when we look out into space is because light has a finite speed, and it requires time to travel from point A to point B. For example, the Sun is 150 million kilometers away. Light takes 8.3 minutes to travel that distance, so the light that reaches us from the Sun actually left its surface 8.3 minutes before. That means that we see it as it looked 8.3 minutes ago.

Outside of our solar system, the distances get huge quickly. The nearest star is a bit over four light-years away, so we see that star as it appeared 4+ years ago. If the star exploded say, 2 years ago, we wouldn't know about it for 2 more years. Don't worry...it probably didn't.

Most of the stars we can see are within a sphere of about 60 or so light years, but of course there are exceptions...very bright stars that are visible to us even from hundreds of light years away. The star Deneb, in the constellation Cygnus, is 1830 light years away. Presumably, that star could have gone supernova anytime since the year 177 AD and we still wouldn't know about it.

So you CAN "see into the past" when you look out into space, but it's not the same as time travel, and it can't ever be used as a means of time travel.

Answer 4

What you're describing is a kind of time travel, while at the same time it's not really. The only reason we're sort of looking back in time is because it takes light from those very distant objects to travel from there to here. If you think about it, we never actually see anything right now. No matter how close something you're looking at is to you, it still takes time for light from it to get from there to your eyes.

Answer 5

Its because light takes time to travel across the universe. Sunlight for example takes about 8 mins to reach the earth so if the sun suddenly dies out now, we'll see it 8 mins later.
The sun is relatively close to the earth, other stars are millions of light years away... so in effect what we're seeing in the skies are things that have happened in the past. And past means thousands, maybe millions of years ago

It has nothing to do with time travel, its just a delay:)

Answer 6

Well, only slightly. Peering into the past via space is still using the constant of the speed of light. Theoretically traveling close to the speed of light will only slow time down, not travel through it.

Answer 7

If you want to do time travel you must travel at a speed of light according to Michio Kaku. I think no one can't do time travel because we will be killed by going at a high speed at 8,000 mph or higher. When you look in to the skies you are always asking your self how did we get here and how did it all began.

Answer 8

what you're seeing is carried by light waves which are not "alive". time travel would necessarily involve remaining intact upon arrival at your destination. in other words, there would be more aspects of physics than simply the electromagnetic force of which light is a part, but light speed would definitely be a part of the solution, if there is one.

Answer 9

light takes time to travel

Answer 10

My Bio teacher was telling me about time travel & how it's possible, but you would need about the energy of so many billion suns . I'm going to read a book he reccommended called 'A short history of nearly everything' by Bill Bryson. Definatley interesting stuff! Glad to see Einstein's theory lives on.