No seriously; Can we, maybe, go to the past?

[Spirit]

Hello everyone,

Perhaps it has been asked many times in the past, so please forgive me, and I appreciate your effort in helping me;

In simple words: Can someone travel to point A the future, sees something, then come back to a certain point 'B' that is considered in the past of point A, and tells people what has happened there.

I know there is a lot of science fiction about it, but I really want to know what real science speaks about it.

[For example, 2+2=5 will never happen, no matter how advanced science will reach, I think. Since it's bounded to logic, too...etc]

 

[Fubini]

I'm not an expert, but there are various mathematical theories that say that time-travel is possible, but those are not realizable because of physical concerns like practical generation of energy required.

There are some people looking into building signaling devices, so that even if you couldn't go back in time as a whole you might be able to send a message back in time. Try looking into the laser time-machine thread also in this forum.

 

[George Jones]

Take a look at https://www.physicsforums.com/showthread.php?p=1065704#post1065704"; my answer is given in post #7, which might be a bit too technical.

 

[rbj]

If I get a chance to go to the past, I'll be sure to sabatoge the romantic relationship between my mother and father (i wouldn't want to kill them, but that would be a method of doing it) and see what happens.

 

[pervect]

If I get a chance to go to the past, I'll be sure to sabatoge the romantic relationship between my mother and father (i wouldn't want to kill them, but that would be a method of doing it) and see what happens.

The literature does discuss this issue somewhat, but of course human beings are too complex to model with physics. Similar paradoxes can be set up with billiard balls, however. A good (though technical) place to start is

http://prola.aps.org/abstract/PRD/v44/i4/p1077_1