Time travel

[KitNyx]

The first step toward time travel (classical sense) is teleportation. I say this because they are the same thing. Both teleportation and time travel are non-contiguous movements through spacetime. Teleportation is movement through the 3 expanded spacial dimensions; time travel is movement through the 1 expanded dimension of time. If we can do one, we should be able to figure out how to do the other.

- KitNyx

 

[Zero Mass]

I was going to respond to what errandir posted, but it is all pretty clean cut and correct.
You did misinterpret a few things I wrote, but you clarified a lot of the other stuff.

It makes time and space very difficult to think about seeing everything is relative. I am traveling through time right now, although unfortunately time is moving rather slow because I am at work, but it is still moving in a linear (relatively linear) fashion.

It is hard to imagine anything other than what we have experienced as far as time is concerned, but do you think that it is possible to have different properties to time outside of all the natural properties that humanity has attributed to it?
Another way to think about that question is, do you think that space-time can ever be so changed as to alter what we consider linear?

Thanks for the smathering of insightful points again, errandir.
I'm going to go take an advil, thinking hurts sometimes...

ZERO MASS

 

[atreides1977]

Originally posted by doom

c)Quantum theory's suggest that when you go back in time youre not in the same universe your in a counterpart quantum system which is the same in every way except you are there,the other universe still exists but is now without you as youve gone in the quantum counterpart,this means you can kill your grandfather,no paradoxes,this is the most likely situation.

ok so when traveling through time you dont travel directly to your destination... thus time travel takes longer and if it takes longer than expected you could run out of fuel. maybe scientist have never expected this and the devise is stuck somewhere in the time/space continuem. it could also be possible that we can only travel fowards in time and not back. technicaly you would have to go negitive the speed of light to do so and i dont think we can move that slow.

 

[errandir]

Originally posted by KitNyx
The first step toward time travel (classical sense) is teleportation. I say this because they are the same thing. Both teleportation and time travel are non-contiguous movements through spacetime. Teleportation is movement through the 3 expanded spacial dimensions; time travel is movement through the 1 expanded dimension of time. If we can do one, we should be able to figure out how to do the other.

- KitNyx

YES! That is EXACTLY what I think, too. That is why I put so much emphasis on quantum mechanics (though, I have mentioned much about relativity, this was mainly in response to other people's posts).

In fact, quantum mechanics is all about discontinuities.

 

[errandir]

Originally posted by Zero Mass
I was going to respond to what errandir posted, but it is all pretty clean cut and correct.
You did misinterpret a few things I wrote, but you clarified a lot of the other stuff.

I appologize.

Originally posted by Zero Mass
It makes time and space very difficult to think about seeing everything is relative.

A useful perspective is to consider the proper time. This is actually an invariant to all observers (but there is one for each observer). The disadvantage is that it can be a bit tricky to manipulate. For any observer, their proper time seems normal to themselves, as we classically think of time as some parameter rather than some dimension.

Originally posted by Zero Mass
I am traveling through time right now, although unfortunately time is moving rather slow because I am at work...

Are you sure you're not confusing time (or even the perception of time, which is more closely related to proper time) with the density of conciousness. There is a 4-D hyper-plane that exists in space-time which is essentially the 3-D spatial universe. The amount of conciousness as a 3-D distribution in this surface determines how slowly time seems to go by for you. When you are sitting and thinking, this usually elevates your density of conciousness, thus, relative to you, the amount of time that goes by seems less.

Originally posted by Zero Mass
...but it is still moving in a linear (relatively linear) fashion.

It is unclear to me what you mean by "linear." Do you mean "in a straight line?" In what coordinate system to you represent this line? There is a very different definition for linear in the rigorous sense (in math and physics). If I were to try to fit the definition to what you said, there would need to be some input function, or at least some parameter on which some operation returns a value for time. If this is what you mean, then what is the input function and operation? If you mean something else entirely, then please explain.

Originally posted by Zero Mass
...do you think that it is possible to have different properties to time outside of all the natural properties that humanity has attributed to it?

Of course. We are always discovering new things. But, we should appreciate the tremendous amount of evidence that we have collected that has verified our current theories about space-time. Although I vociferously declare "of course," I will point out that I think DRASTIC alterations of our current notions are highly unlikely.

Originally posted by Zero Mass
Another way to think about that question is, do you think that space-time can ever be so changed as to alter what we consider linear?

Again, I need some feedback from you for clarification of your term "linear." You don't seem to be using it in the rigorous mathematical/physics type context. I'm not trying to say that there's anything wrong with it, just that a particular definition has been drilled into my head, and, in order to consider another one, I need to hear it from you.

 

[errandir]

Originally posted by atreides1977
ok so when traveling through time you dont travel directly to your destination...

If your destination is a particular point in time, then alternate universes don't inhibit pin-pointing such a destination. They do inhibit certain consequential problems with causality, which is, I'm pretty sure, the point that doom is trying to make.

Originally posted by atreides1977
thus time travel takes longer and if it takes longer than expected you could run out of fuel.

How long do you expect it to take? And what do you mean by "long?" Long in the sense of: and hour is longer than a minute? That is all relative to the observation point. There is a proper time, the duration of which would depend on the mechanism for travel. If we use relativity (alone), then there will be some finite proper time interval for the journey (and, I imagine that this will exceed any reasonable amount of time for a nontrivial journey). What quantum mechanics would allow is quantum leaps. This is just a discontinuity in a physical construct (such as space-time, or more relevently, the time coordinate of space-time).

Originally posted by atreides1977
...the devise is stuck somewhere in the time/space continuem.

Stuck? Do you mean that maybe it is now in some alternate universe?

Sure, that is exactly what I believe would happen if we tried to create a time-traveling device, but not because it runs out of fuel; because that is the price of making such a leap (in order not to violate causality). Perhaps there is some parallel universe (as opposes to the multiverse structure that has been assiduously suggested).

Maybe it is like the other side of a conveyer belt (there are some who entertain the notion of a universe that closes on itself; the movement of the belt represents the flow of time). In order to travel back in time, you could either wait until the belt went all the way around (which would require waiting he cyclic period of the universe - a VERY long time, and rather impractical), or, if you are ingenious, you could jump to the other side that is moving backwards. Some have speculated that the other side could somehow be pulled closer to you by gravity (a black hole), though not the way I've seen it mentioned on this thread. But, even with all of this speculation, I don't think that it is an issue of fuel being expended continuously throughout the journey; I think that it an issue of having enough fuel to provide the means for jumping back to the original side of the conveyer belt. If this was not accomplished, then the device would be, as hollywood says it, "in ANOTHER DIMENSION." (Please note that this use of the word dimension is very different than the way I use it, but most people get the gist of this phrase.)

Originally posted by atreides1977
it could also be possible that we can only travel fowards in time and not back.

According to my understanding of general relativity today, anything with mass is doomed to have a proper time that shares the same sign as all other coordinate time - at best, the world line may be at just under 90deg to some time axis (meaning somewhat in the same direction).

Originally posted by atreides1977
technicaly you would have to go negitive the speed of light to do so and i dont think we can move that slow.

This statement does not make any technical sense, so let's not say "technically." But I think I see what you're saying. There are things that do theoretically do just that; they are called tachyons, but they have never been observed/proven, and I don't know of anyone (whose opinion on the matter I would absolutely respect) who takes them very seriously.

 

[atreides1977]

i see your point errandir... hey take a look at my fission/fusion stars thread in the Astronomy section. you might find it interesting