Who invented time travel?

[xaqintosh]

to macluv: all this predicting of posts doesn't mean anything, you merely altered something you wrote before *after* someone else wrote something else and said that it happened, technically after and not before it happened

[RacerX]

MacLuv,

The thread can only be used as a history of events (post), and not for travel in time to those events. Like history, a thread can be altered later to show events that didn't actually happen (editing of post by members, moderator and administrator). In that way a thread is no more valid a reference than a diary.

When I spoke of reference frames I was treating every event as being completely unique in space-time. Every event has a unique place in time and a unique place in space. We are constantly traveling away from any given event in both space and time. To travel in time back to some event you would also need to find it's place in space. Because the universe is not static (the Earth rotates on it's axis, the Earth orbits the Sun, the Sun orbits within our galaxy, and the galaxies move apart with the expansion of the universe) finding the relative space where an event took place would be as hard as producing time travel to begin with. When dealing with most of the equations used in relativistic theory, we tend to normalize all the parts... that is make the units of measurement the same for all elements, and then treat the parts as unified (in this case space-time is treated as a four manifold called Minkowski space). From there we would enter the area in which I specialized which was the differential topological nature of m, m+1 and m+n manifolds (I worked in mathematics, not physics, so I didn't stay with the strict modeling of nature).



Anyway, that was what I would consider the biggest hurdle to any theory of time travel. Traveling in time is also traveling in space, and the distances between us and past events get larger by the second.

As it can not be produced, no one has yet to invent it. The concept is universal (one doesn't need science to wish to change or revisit the past), so the first person to conceive of it would most likely be unrecorded. But I would like to hear who you think invented it.

Originally posted by brianleahy
Likewise, there are no fixed reference frames for spatial travel either, yet it is possible.

Not really. Actually spatial travel can not be removed from time travel. We all move from place to place within a dynamic system which is changing over time. But to travel backwards in time would require moving the system backward to also find the exact event.

Also the theory of relativity predicts (and has been observed) that all of the dimensions are distorted by gravitation and velocity. The Lorentz transformation applies to both space and time of any reference frame. And the only fixed frame of reference is the speed of light (which is constant in all frames of reference). Light is effected by gravitation so time is also effected. Inside a reference frame which is moving, (which everything is) the speed of light must appear as a constant. That means that both space and time must be altered to make it appear as that constant (again by using the Lorentz transformation).

If backward time travel is possible, then it seems logical that these - and perhaps other - forces would govern an object's timelike path.

Actually, as travel backwards in time is not possible, the idea that you could have the forces that governed our movement forward to help you would not be a factor (in a system where it was possible, maybe though, but we would see time travelers moving with us then as they would have to co-exist in with us to have those same forces act on them). Most theories of time travel require a bridge between the two relative places in space-time. Also, as I pointed out earlier, moving freely backwards in time intoduces conservation of energy problems (though that is most likely not the part of the subject that people would find interesting, it is a governing and restrictive factor none the less).

[kendall]

After seeing MacLuv's returning post and the ensuing posts of various users, I feel like I've just watch Star Wars, A New Hope and The Empire Strikes Back, back to back.

I am still awaiting the Return of the Jedi.

[JohnnyV]

The first time traveler was the first person to read a book/wall/symbol. The inventor of Time Travel was the author of the book/wall/symbol. Go Read.

[JohnnyV]

Do I win?

[xaqintosh]

I don't think reading a book counts as time travel. In that case, doing anything is time travel because you are interacting with something that *was* in the past.

[kendall]

what time is it?

[xaqintosh]

6:54 EST