I registered to comment on this topic. I believe that we are all looking at this wrong.
First, clearly time travel IS possible. Someone jokingly pointed out that we are traveling forward in time always. That isn’t just a joke, it is a fact that needs to be considered. Second, others have mentioned Einstein’s special theory of general relativity which hypothesizes that the laws of physics are the same for all non-accelerating observers and that the speed of light within a vacuum is the same no matter the speed at which an observer travels.
This allows for a different kind of time travel. It allows for us to travel forward in time (in theory - assuming we could overcome the difficulties involved) at a much faster rate of speed than “normal.” This has been observed in space travel already.
There are tremendous implications here. Time is clearly not the constant we imagine. It is only a constant to the observer and is highly dependent on the velocity of the observer. An observer not moving at all may not experience time. Perhaps we are all experiencing time at the rate we do based on the speed of our planet revolving around the sun, and the speed of our solar system traveling through space and the speed of our galaxy traveling through the universe, none of which are negligible. What is time like for an observer moving at virtually zero mph?
And the faster we travel, the closer we come to time disappearing into infinity. Sounds a lot like God talk…
Here’s where I think we fail. We make assumptions based on our senses. I like to consider a 2 dimensional man. Imagine the world to him. He simply cannot fathom things that are simple to us. For a two dimensional man, a circle looks like a straight line coming towards him. A straight line that is getting larger and larger. A line might look like a dot sometimes. It might look like a “line” at other times, depending on the angle at which the line is turned towards him. If he was looking at the line perpendicularly it would look like a massive line, or wall. If he was looking at it from 90 degrees off of perpendicular, it would look like a dot.
My point being that we are in a 3d world with five senses and we have also created equipment that can measure other things within our dimensions. You could make an argument (that I would not be comfortable with) that time is the fourth dimension. But I find that hard because time seems very malleable - or at least it is not a constant - except from the observer’s pov.
Time seems to be a construct or an invention. Something created so that we can experience a 3d world in a sensible way.
There is so much interesting discussion to be had on these topics. I am not challenging or arguing with anyone, just trying to learn more and trying to see if there is a way to understand something that is clearly on the outer edge of our ability to comprehend. It may simply not be something we can understand from our limited perspective. Like the 2D man trying to comprehend 3D structures. But it is fun to try.
I’d love to hear from anyone with theories and ideas on this topic.
One thing that does SEEM to be impossible is traveling in time BACKWARDS. It appears that anything that has happened is unchangeable. I can’t prove that, but I also haven’t heard an argument that would allow for it happening and it seems to create paradoxes and other impossible situations.
Time Travel seems to be limited to changing the speed at which we can travel forward, slower or faster.
-Tom Steele