Is Time Travel Possible as Depicted in Movies?

[campal]

that's good food for thought. sometimes i wunder if time really exists. just because you can use it to callculate projectil motion or whatever, is it actually a physical issue or is it just the human way to deal with a situation? do you know what i mean? what if clocks can tell your passage from the past to now but nothing actually happened in physics, only things that can age have, from diferent forms of decay. if time is not real then time travel would not be possible and a lot of the physics equations would be wrong...E=MC^(2)?

 

[ptalar]

that's good food for thought. sometimes i wunder if time really exists. just because you can use it to callculate projectil motion or whatever, is it actually a physical issue or is it just the human way to deal with a situation? do you know what i mean? what if clocks can tell your passage from the past to now but nothing actually happened in physics, only things that can age have, from diferent forms of decay. if time is not real then time travel would not be possible and a lot of the physics equations would be wrong...E=MC^(2)?

I am not sure time exists either. Just change. Stars are born, die. People are born and die, etc. Time is a frame of reference created by man to measure change. Information exists though and if one can travel at multiple speeds of light they can view the past by viewing the light as it reflects off the earth. If one had a super powerful telescope and could travel to anywhere in the Universe in an instant, one would be able to say travel instantly 100 light years away from Earth and be able to watch events as they unfold on Earth for the past 100 years as if they were there. Of course you would have to travel 100 light years in an instant which is 600 trillion miles. At sub light speeds we only travel into the future.

 

[malawi_glenn]

i think it is possible with much more research.

I think it is possible to do squared triangles with much more research

 

[DaveC426913]

Just to address a few misconceptions:

and past the speed of light time goes back wards.
...

No object with mass can reach - let alone exceed - the speed of light. No object without mass can travel at less than the speed of light. NBothing can cross the barrier from <c to > c.

However, hypothetical particles (called tachyons) travel faster than the speed of light, yet still cannot slow down to c. They would, if they existed, appear to be moving backwards through time.

Does this huge mass increase make an objects gravitational force so immense that

The mass increase due to relativistic speeds does not increase an object's gravitational force. The mass increase is from an external observer's POV. The object reads its mass as normal.

 

[robheus]

none of that sounds stupid at all. those paradox are complexing questions theoretical physisits ask all the time. the answer is no one knows. many people believe that time travel will never happen based upon those reasons. so i guess we will just have to wait and see what happnes, if it ever does. and yes the interdimensional travel is one theory out now, but again, no one knows for sure exactly.

All of our current physics is based on only one dimension and direction of time,and the only deviation that relativity brings in that two independent frames of reference might have different "speed" of time (time dillatation), with as a consequence that two clocks can get out of sync without any mechanical/techincal failure, but solely due to relativistic effects.

I don't know if physical law is possible at that basis of another, independent dimension of time, I would guess that it is not a possible physical reality.

And if that is not the case, then there is no possibility of time travel.

One might consider the case in which not just the speed of time (which is a possibility based on relativity) but also the direction of time could change.
However, I would guess that inverting the direction of time would in fact not be different at all, since in such a case all physical laws is time-inverted too, including the physics of our brains, and we would (in this opposite directed time) remember the future (which is the past in our normal flow of time) and would not be aware of anything different.