The Fundamental Principle of Time Travel
You're in the forest with a rope. You tie one end of the rope around your waist and the other end around a tree trunk, you walk backwards to remove the slack, then you pull on the rope.
When you pull, that "pull energy" travels the length of the rope to the tree, reaches the tree and an instant measurement takes place- your weight (or mass or gravity... whatever it's called) is far less than the tree's, you have no chance of pulling that tree towards you.
The pull energy then reverses itself and travels back down the rope again towards you, in reverse. That pull-energy returns to you as a "reverse-pull": you end up being pulled towards the tree, not the other way around.
In short, you trying to pull that tree down only made the tree end up pulling you.
Now you're in space. You tie one end of a really long rope around a boulder on the moon and the other end around your waist then you jump off into space.
You float away from the moon pulling the rope along with you. 300,000 kilometers away in space, you come to the end of the rope. You reach your arms out and grab the rope and pull hard. What happens?
The pull-energy travels the length of the rope- 300,000 kilometers- towards the moon, reaches the moon then reverses and comes back the same 300,000 kilometers towards you in reverse, you end up getting pulled towards the moon.
The flaw in this equasion is that the universe is relative to light and light travels at 300,000 kilometers per second. So when you pull the rope, it takes one light second for that pull-energy to travel the rope and one more light second for it to come back to you. And since the universe is relative to light, nothing can happen before light speed... you have just created a paradox.
In short, you pull the rope, nothing happens for two seconds, then you're pulled towards the moon. That two second window between you pulling the rope and the rope pulling you back is your window to travel through time. The effect is apparent, depending on the point of view.
-If you're standing on the moon watching this, it appears normal.
-If you're the astronaut on the end of the rope, it also appears normal.
-If you're an observer somewhere between the moon and astronaut, at some point you will see that astronaut blink out of existence and instantly reappear "two light-seconds closer to the moon".
You catch up to the observer and compare your atomic clocks. Apparently you just travelled two seconds into the future although you have no memory of doing it.
This is the fundamental principle of time travel. There are two vectors to control time travel:
Point A is the astronaut at the end of the rope
Point B is the astronaut's hands on the rope
Point C is the moon
One of the vectors is the "rope-pull energy": the pull itself and the time it will take for that pull-energy to come back (B to C then C back to B). The second vector is the space between A and B; the distance between you and your hands. The first vector (B/C) is unchangable and dependant on light speed; classical E=MC2 will give the precise measurement for this, the second (A/B) is very small and very changeable.
For example, if you pulled the rope then pulled even harder before that initial pull-energy came back to you, you might find yourself four seconds in the future. Conversley, if you pulled the rope then let go and hit your space suit's boosters zooming you away from the moon even further you'll find yourself moving backwards in time. The initial pull-energy returns to the theoretical spot you're in and "time catches up with you" and you find yourself 4 seconds in the past.
Through manipulation of the space between A and B while the rope pull energy is going from B to C then back to B, you can control where in time you want to go.
End of part one.
NOTE:
The Heisenbergian problems associated with this thought experiment are nominal. That is, this is not impossible to actually do.
You're in the forest with a rope. You tie one end of the rope around your waist and the other end around a tree trunk, you walk backwards to remove the slack, then you pull on the rope.
When you pull, that "pull energy" travels the length of the rope to the tree, reaches the tree and an instant measurement takes place- your weight (or mass or gravity... whatever it's called) is far less than the tree's, you have no chance of pulling that tree towards you.
The pull energy then reverses itself and travels back down the rope again towards you, in reverse. That pull-energy returns to you as a "reverse-pull": you end up being pulled towards the tree, not the other way around.
In short, you trying to pull that tree down only made the tree end up pulling you.
Now you're in space. You tie one end of a really long rope around a boulder on the moon and the other end around your waist then you jump off into space.
You float away from the moon pulling the rope along with you. 300,000 kilometers away in space, you come to the end of the rope. You reach your arms out and grab the rope and pull hard. What happens?
The pull-energy travels the length of the rope- 300,000 kilometers- towards the moon, reaches the moon then reverses and comes back the same 300,000 kilometers towards you in reverse, you end up getting pulled towards the moon.
The flaw in this equasion is that the universe is relative to light and light travels at 300,000 kilometers per second. So when you pull the rope, it takes one light second for that pull-energy to travel the rope and one more light second for it to come back to you. And since the universe is relative to light, nothing can happen before light speed... you have just created a paradox.
In short, you pull the rope, nothing happens for two seconds, then you're pulled towards the moon. That two second window between you pulling the rope and the rope pulling you back is your window to travel through time. The effect is apparent, depending on the point of view.
-If you're standing on the moon watching this, it appears normal.
-If you're the astronaut on the end of the rope, it also appears normal.
-If you're an observer somewhere between the moon and astronaut, at some point you will see that astronaut blink out of existence and instantly reappear "two light-seconds closer to the moon".
You catch up to the observer and compare your atomic clocks. Apparently you just travelled two seconds into the future although you have no memory of doing it.
This is the fundamental principle of time travel. There are two vectors to control time travel:
Point A is the astronaut at the end of the rope
Point B is the astronaut's hands on the rope
Point C is the moon
One of the vectors is the "rope-pull energy": the pull itself and the time it will take for that pull-energy to come back (B to C then C back to B). The second vector is the space between A and B; the distance between you and your hands. The first vector (B/C) is unchangable and dependant on light speed; classical E=MC2 will give the precise measurement for this, the second (A/B) is very small and very changeable.
For example, if you pulled the rope then pulled even harder before that initial pull-energy came back to you, you might find yourself four seconds in the future. Conversley, if you pulled the rope then let go and hit your space suit's boosters zooming you away from the moon even further you'll find yourself moving backwards in time. The initial pull-energy returns to the theoretical spot you're in and "time catches up with you" and you find yourself 4 seconds in the past.
Through manipulation of the space between A and B while the rope pull energy is going from B to C then back to B, you can control where in time you want to go.
End of part one.
NOTE:
The Heisenbergian problems associated with this thought experiment are nominal. That is, this is not impossible to actually do.