Do i understand this right!!

mcgarry098

Didnt want to post this in the thread for the breaking of the thoery of relativity as it would be off topic.. But i just want to see if my understanding of how time travel could work is right!

My understanding is : you are standing at a point named "x". There is a tree blowing in the wind 50m from where you stand ( we'll call the area where this tree stands "y"). 50m after that tree there is another tree which is also blowing in the wind ( we'll call the area where this tree stands "z").

Now when you see the the tree known as "y" shake you are only seeing the tree shake a fraction of a second after it actually did, as it took time for the image of the action to reach you. We'll say that the speed of the action of the tree shaking to reach you was 5 m\s (lets call this speed "r").

At the same time as tree "y" shakes tree "z" shakes as well but lets say the speed of the action of tree "z" shaking to reach you was travelling much faster at a speed of 15 m\s (lets call this speed "s")

Since the speed "s" is going 3 times as fast as speed "r" the action of the far away tree (tree "z") will be seen by you before the action of tree "y", and since the speed "s" will pass through the closer tree (tree "y") it will bring the action of tree "y" to you before it actually happens, thus you have time travel.



Is that how it works!!!! Ive read a bit about it my im still unsure if i have it right but would love to know!

Thanks alot,

p.s. you'll probably have to read this several times to understand it but its as simple as I could put it!!! If you dont understand what i mean please post and I'll try to explain it.

Well there's a few things in your post I'm not getting (I'm far from an expert though, I don't know much about time travel at all, I'm just going on some basic physics):

How is it that two images are reaching you at different speeds? They should both be travelling at the speed of light.

How is the speed of the far tree "passing through" the other one? Speed is a property based on time and distance, it can't "pass through" stuff, unless I'm misinformed of course?

I'm well aware that often, the more you learn about something, the more you're told that actually all the basics are wrong, so I could be totally off the mark, but your post would suggest to me that you're not quite getting it.

FISMA

mcgarry098,
Currently, we can lose time (google the twin paradox). But we cannot go back in time.

If it were possible to go faster than the speed of light, then we'll have a lot of explaining to do.

If you could go faster than the speed of light, the effect could occur before the cause.

For example, for a person shooting an arrow that could go faster than the speed of light, the arrow could hit the target before it was shot. What? :eek::eek:

It's the kind of place that our brains don't like to go. We just don't appeared wired to get anything other than linear time.

mcgarry098

thanks for the reply's lads,

(i dont mean this in a cheeky way i just mean is it one of these things with no explanation that we have to take to be true) Fisma do you actually understand how the arrow example works or do we just have to take it for granted that its true!! Like why should the effect happen before the cause just because it can go faster than light!

True or False: Lets just say image one was sent using light and image 2 was sent using nutrinos (im saying neutrinos can travel 3 times faster than light to make it easier to understand). Since the neutrinos are travelling 3 times faster than light they reach the observer (x) first. Now say the tree "z" shook a few seconds before the first tree, the action of tree Z passing over the first tree feels the affect of the shaking of the first tree before it has actually happened because if the neutrinos where indeed light the light WOULD feel the action 2 seconds (this is just an number im picking out of my head) after the action of tree z,. but because it was indeed neutrinos that were sent and not light the nuetrinos feel the affect of the first tree after only 1 second and thus the first tree's action hasnt actually happened!

I realize that that is impossible to understand but thats the best I can do!!

Thanks again, this is mind boggling stuff lol

Well, with regards to neutrinos, the whole "faster than the speed of light" thing is far from proven at this stage, and if it is true, pretty much all of physics is going to have to be revised. So I'm going to have to bow out here, as I'm far from qualified to understand the consequences of such a discovery. And also your description of different trees feeling the action of each other is very confusing. Maybe you could clear that up for future replies.

I would mention though that if anything moved faster than the speed of light, then yes theoretically it would have time traveled.

mcgarry098

ive come to the conclusion that i am wrong with what im saying!!

Why is it that just because something "can" go faster than light it is said to have time traveled,....

Cheers,

cooperguy

FISMA wrote: »

mcgarry098,
Currently, we can lose time (google the twin paradox). But we cannot go back in time.

If it were possible to go faster than the speed of light, then we'll have a lot of explaining to do.

If you could go faster than the speed of light, the effect could occur before the cause.

For example, for a person shooting an arrow that could go faster than the speed of light, the arrow could hit the target before it was shot. What? :eek::eek:

It's the kind of place that our brains don't like to go. We just don't appeared wired to get anything other than linear time.

I dont understand how that arrow would have time travelled! We would see the effect (arrow hitting something) before we would have seen the cause (arrow being shot) but the two would have happened one after the other in the right order. In other words the arrow wouldnt hit the target before it was shot, it would just have hit it before the shot was witnessed by the observer.

Am i right in saying this?

mcgarry098

Right my physics teacher told me today in very very simple terms how "time travel" theoretically could happen! I dont remember it 100% but it went something like this: Im changing numbers to make it easier to understand. Also we're going to say that for light to travel from the moon to the earth it takes 5 minutes.

A murder has just being committed on the moon and the police don't know who did it, so the police man on the moon uses a telephone which can somehow go faster than light to ring another police officer on earth. he tells the police man on earth to look up at the moon as a murder has just occurred there and that the image of the murder is on its way to earth (since images are formed\transferred\transported by light) and that he will see the murder take place in approximately 5 minutes time(thats the time it takes light to travel from the moon to the earth!!).

Thus the man can look back into the past and see who committed the murder.


Really it isn't time travel as in literally travelling through time which is utterly mind boggling and stupid which i though it was :P

Also it really is just saying that when we see something happen we really only see it happen a fraction of a second after it actually did as it takes some time for the light to bring the image to us,, all be it a very tiny fraction of a second!



cheers lads