posted on Dec, 2 2004 @ 01:15 PM
There are ways to accelerate and deccelerate time.
Einstein (being the genius that he is) accurately predicted that space and time are not mutually exclusive, so we should really describe things
relatively through "space-time".
Here is an EXTREME simplification of how time is slowed down.
Suppose that we have 5 "units of movement" which we use to move through "space-time". We can use those units to either move through 5 units of
time, or 5 units of distance.
If we move through 5 units of distance, we won't move in time at all. Essentially, our bodies won't age and we'll be frozen in time as we travel
through that 5 units of distance.
If we move through 5 units of time, we won't move anywhere in space.
The actual equations are much more complex... I can't remember exactly, but time dilation is not directly proportional to velocity. I think it's
t'/t = SQRT[1 - (v/c)^2]
so it's obviously not directly proportional, but at least it's obvious that the greater the velocity the more time become dilated. If v = c (speed
of light) then basically t' = 0 (time change is 0, meaning you're frozen in time).
Note that our current equations don't even allow v > c because that would create a negative under the radical. However, if we tried
(t'/t)^2 = 1 - (v/c)^2
we'd still have to account for the fact that the velocity needs greater than the speed of light for anyone to travel backwards in time.
This is not possible because classical physics breaks down near the speed of light. Photons are able to travel at or near the speed of light because
they have no mass. If you took even an electron and tried to accelerate it to the speed of light, you'd notice that the amount of force required to
accelerate it begins to increase once you near the that terminal velocity of c. This is because, as Einstein said, E=mc^2. The more energy you put
into the electron, the greater its mass becomes (because energy IS mass), so the more energy you'll need to accelerate.
This creates a catch-22.
- You need to put more energy (mass) into a massive object to accelerate it than you would for a light object.
- The more energy you put into the object, the more massive it becomes.
No, it's not possible to travel backwards in time with our current Einsteinian understanding of space-time topology.
Now, is it possible to shift a specific object back in time (as in reverse the aging process)?
Theoretically, THAT is possible.
Entropy (chaos) is commonly described as "the arrow of time". Reversing entropy would technically have the effect of reversing time.
Reversing entropy, however, is a statistical improbability if done on a large scale.
On a small scale it's possible to reverse the entropy of a system by drastically increasing the entropy of its environment to counterbalance the
decrease of entropy of the system. That is the only way. We can't reverse the entropy of the universe to "travel back in time" because the entropy
of the universe always increases (2nd Law of Thermodynamics). We can only reverse the entropy of something small scale (by making sacrifices on the
large scale).