taog

"Just to comment about that infinite future thing and how we'd be overrun with time travelers, well there's one option that was left out, and that is that there isn't infinite futures in the first place. It has not been proven."

No, but if time travel is more common in the future, like he said, I would assume that we would also know that time travel is more common. More people would have travelled back through time and let us know that it's more common. 2063 or whatever date he gave isn't all that far away.



I want to direct the rest of this post to stingc, and anyone else who is interested. You got me thinking about all this time jazz, and different views on time travel.

First off, nice post, and well worded.

I wanted to kind of go into the whole idea of what we think time travel is.

I always get a little mixed up when it comes to explaining time travel, or the possibility of it. I look at time as being defined differently than most people, and thus, I look at time travel a little different, in a way.

You got me thinking about the different types of time travel.

Like i stated above, which you might be able to verify, if one were to move faster than the speed of light, lets say they could, then do you think their rate of time would then start moving negatively? In other words, do you think they would be able to start becomming younger?

I look at it like this

The following is all in reference to something at rest.

Now, you have a person who is stationary. Their time is moving at a given speed, lets say t0, since they are at rest, and their speed is some value less than the speed of light, lets say v0, which is c, the speed of light, minus v, their speed, 0. So, you would have c as their difference in speed from the speed of light.

Then, you have someone moving the speed of light. Their time is moving at a rate of 0, and their difference in speed compared to the speed of light is 0.

Now, you have someone moving faster than the speed of light. Their difference in speed from the speed of light is the same, but opposite to, the first speed, at rest.


Given these three situations, you would expect that the first one be us, on earth, moving at the same rate of speed as everyone else.

In the second one, the person moving would not be aging at all, but everyone else would be aging at the rate of the first one.

In the third one, the rate of time change would be equal to, but opposite the first. You would be aging, negatively, at the same rate that everyone is aging, positively.


Now, I don't like this idea. I dont' know if this is fully correct, but that is, kind of, what special relativity says. To me, this doesn't sit right and must be impossible, but I can't grasp the words to explain why. I'll try, though.

I keep going back to thinking about the direction of time. I wish I had a brief history of time here, which is where i read about this, where it talked about different types of time. Space-time, which i believe is what we are talking about, is moving in a forward direction, and always will, unless the universe starts to collapse on itself.

Where this gets tricky is when we start talking about what we are viewing as time. Are we actually talking about our space-time being manipulated when we move faster?, or, are we talking about some other type of time? I believe Hawking touches on a theory of time called destructive time. It is also moving in a forward direction for every object, and is dependent on that object. If i am correct about this, this is the time that time dilation refers to. These times will be related, since they live in eachothers worlds. Destructive time can be explained by an object falling off of a table, lets say a cup, and breaks. That object is on it's way to destruction. It can be slowed down so it takes less time to break, if it were to be moved at a faster speed (you would have to move the whole falling object, not move if faster to it's destruction), but it will never reverse and fix itself.

I think this is because you would have to then manipulate the direction of space-time for this to occur.

So, to manipulate your direction of time, you would then have to manipulate the direction of space-time, which is defined by the expansion of the universe. You would have to somehow change the direction of space-time. The only way to do so is by waiting for the universe to collapse on itself, if that will ever happen. Even still, if space-time does start going backwards, due to collapse, does this mean our 'destructive time' will also change direction? Will the cup go back and fix itself?

If you think about our current universe, destructive time kind of makes sense. Ever since the very beginning of the big bang, things have become more and more out of order. It would explain why there is an over-abundance of particles in relation to anti-particles, though probably not enough, but it kind of goes with the whole idea.


Anyway, given this information, which is probably more my way of looking at things, without any proof, rather than anything scientific, the situations i showed above would seem to be impossible. Maybe that's why Einstein's formula about calculating rate of time for a given speed falls apart at speed = c.

Anyway, like I said, I read something about this destructive time stuff in a book somewhere. I believe it was in 'A Brief History of Time', by Stephen Hawking, which is a good read. Either way, the whole idea is to not just base time on one scale. Time seems to have different effects on different things, and seems to be independent for different things, but dependent on everything as a whole (space-time). It's interesting to think about.



Oh, something that also makes me think about defining different types of time and such, and goes with the idea of a space-time and a destructive time (our individual time).

Light seems to be independent of our time. It seems to move with space-time, rather than our time. Something that seems to show this is the fact that, no matter how fast you are moving, light is always measured to be the same speed.

This kind of suggests that space-time is always moving at a constant rate, and we can never manipulate it. That makes sense to me. Our time is what we are manipulating. Space-time moves forward, at a given rate, and our times are within that space time, independent of space-time.

Since they are both a type of time moving forward, at a given rate, they will be somewhat dependent of eachother. One thing that would be dependent between the both would be their direction. Like i said, our rate wouldn't be able to exceed the rate of space-time (you can't move slower than a velocity of 0), and our rate can't go slower than space-time (you can't move faster than light). If you were to do either of these, and succeed, you would have to manipulate space-time.

Any thoughts on this?