Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Time travel into the past a possibility now?

  1. Mar 1, 2014 #1
    Hi, I don't know if I am in the right sub forum or if this topic has been discussed but I'll ask anyway. so I don't think travel into the future beyond what hasn't happened yet is possible and believe it or not, it sounds more possible to me to travel into the past since the past already happened although there are people who think time is nothing more then a man-made construct or just motion so people would always be in the present and once the the past moment/event is gone, its gone for good. if it was possible for a person to travel into the past then is it current excepted scientific theory that one could not change the future or present of the past by traveling into the past or trying to change events in the past? it's like one theory I saw on a science program regarding billiard balls, maybe your familiar with it. and if a aclubare warp drive space ship is ever created(see here http://www.youtube.com/watch?v=kdaMI2wnVBg&list=LLDAnCRZw9SMDaz836h9eotQ&feature=c4-overview) then if the spaceship travels sideways going left or right, I forget witch one then couldn't one travel into the past? even before the spaceship was made?
     
  2. jcsd
  3. Mar 1, 2014 #2

    Chronos

    User Avatar
    Science Advisor
    Gold Member

    Traveling into the future is easy, we do it everyday. Traveling into the past invokes causal paradoxes. Could you prevent construction of the device that enabled you to time travel?
     
  4. Mar 1, 2014 #3
    yes of course I'm familiar with that but I mean like traveling into the future faster then normal, say a person travels 1000 years into the future in 5 minutes. I don't think it can happen because the future hasn't begun yet. If you can travel into the past and anything you can do in the past doesn't effect the future then you can't prevent construction of the device that enabled you to time travel. of course if you could effect the future bye traveling to the past then there is the problem of paradoxes.
     
    Last edited: Mar 1, 2014
  5. Mar 1, 2014 #4

    PeroK

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    This is perfectly possible if you were able to travel fast enough. If there are ever space flights at near light speed, then astronauts will return many years younger than the people left on Earth.

    If the spaceship was fast enough, then they could return to Earth a few months or years older to find the Earth aged 1000 years.
     
  6. Mar 1, 2014 #5
    Backwards time travel has been postulated in areas of extreme space-time distortion. For example an area of space-time in vescinity of two colliding black holes.

    If you built a spaceship capable of navigating through such distorted space, and somehow manage to escape the gravitational flux of this enormous catastrophe, its plausible that you would be able to travel back in time (depending on the path you take through the flux). The limitation here is that you would not be able to travel further back in time than a moment right after you first begun entered said warped space-time.

    For clarity; your backwards time travel is limited to the moment when your time machine is first switched on.
     
    Last edited: Mar 1, 2014
  7. Mar 1, 2014 #6
    so traveling 1000 years into the future on earth in five minutes if you travel fast enough is possible but if you do succeed in doing that then will the universe have aged to? I'm thinking yes.

    why is that?

    also if a aclubare space ship goes back in time then the aclubare spaceship can't go back further then when it was first turned on? I'm thinking that if a aclubare spaceship goes back in time a second further before the universe was created then it will implode and everything inside it.
     
    Last edited: Mar 1, 2014
  8. Mar 1, 2014 #7
    Once you enter the space-time vortex (caused by the two colliding black holes that I described in my previous post), you are free to live out the rest of your life (while inside the vortex). Than finally, once you're ready, you would re-adjust your heading taking you on a course 'back in time' out of the vortex.

    If successful, you will emerge just in time to see the younger you going in.

    An outside observer will see you going in, than a second later coming out. The observer would have aged a second, while you would have aged a lifetime - becoming the first backwards time-traveler in the process (albeit, in your own time frame).

    I'll add;

    The above backward time-travel scenario I just described can be supported by currently accepted physical theories - specifically; General Relativity. Traveling back in time as you've described however is currently not supported. Why? for many reasons, but mostly because of the reason other posters have described; Causality paradox.

    Of course, one can create a new framework that would allow such a venture (E.G. a variation of the Multiverse theory), but such a thing first has to be mathematically proposed and than proven before it is even remotely accepted.
     
    Last edited: Mar 1, 2014
  9. Apr 22, 2014 #8

    berkeman

    User Avatar

    Staff: Mentor

    Thread closed for Moderation...


    EDIT -- this thread will stay closed.
     
    Last edited: Apr 22, 2014
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Time travel into the past a possibility now?
  1. Time in the past (Replies: 17)

Loading...