Class weblog
Time travel: what’s the logic?
I saw a program called “The Universe” on H2 yesterday. Physicists talked about the theory of relativity and time travel. One prominent physicist said “don’t be shocked if someone from the future comes knocking on your door one day.” I must say I don’t understand the logic behind time travel or this statement.
Suppose time travel will happen some day in the future then why have we not yet seen someone from future? One argument might be that time is infinite and we are living within a small speck in the infinite time dimension so we have not yet seen anyone who decided to visit this specific speck. May be. But what about visiting during my grandfather’s time? Or his grandfather? Or his father … i.e., why don’t we have a single recorded event in all of human civilization of someone from future visiting us? The only explanation I have is that they haven’t revealed that they are visiting from the future. But why not? Why does revealing the fact affect time travel?
I must say I don’t get the logic behind time travel. If time travel existed, then we should have already seen the future and also obtained time travel technology from someone in the future. How can time travel be logical? Someone please enlighten me.
Comments are closed.
about 1 year ago
Time travel is full of paradoxes and lot of them puzzled me for a long time. For example, if someone goes back in time and kills his grandfather, it is impossible for him to be born in the future (to kill himself…)
Recently, I watched a program on BBC which was hosted by Stephen Hawkings which clarified most of the confusion. He says that it is impossible to travel back into time as that would lead to cycles of energy travelling back and forth between different time zones till it destroys its self. Since travel back in time is not possible, most of these paradoxes are laid to rest. And that is probably we haven’t seen a time traveler from the future.
However, it is possible to travel forward in time and that is a relatively simple endeavor based on relativistic mechanics. If you travel close to the speed of light you can “sort” of freeze time for yourself so that time around you passes really fast and you end up in a future time period.
Another question that arises then is what is the value of future time travel for the present society. I personally think that it might be beneficial for the select few who travel forward in time, but as a society you don’t gain anything from the knowledge these people acquire.
about 1 year ago
Great comment, Vibs. Do you have a link to the BBC program?
about 1 year ago
Here is a link the series of videos:
http://www.disclose.tv/action/viewvideo/44880/Stephen_Hawking__Time_Travel_pt_1_5/
about 1 year ago
Your thoughts on time travel make alot of sense. I have never really thought of it like that before. I think you have more logic than the physicist.
about 1 year ago
it’s been a long time since i read it but one explanation given by Kip thorne in his book “Black Holes and Time Warps: Einstein’s Outrageous Legacy” is using the Chaotic Inflation theory.
If i remember it correctly, they have a chapter where they say that going back in time can only be possible if the time traveller travels to other parallel universe.
and according to , Linde and Vanchurin calculated the number of these universes to be on the scale of 10^10^10000000.
if so, it could be purely by chance that no one visited our version.
not sure how outdated or wrong this is.
but the coolest thing i think is the alcubierre drive.
a real “warp drive” which is sound in a general relativity framework. Saw this on a some program hosted by Michio Kaku. but it would require massive energy to create a singularity.
http://arxiv.org/abs/gr-qc/0009013
about 1 year ago
Thanks guys. DK, I have to read more about parallel universes. Somehow that notion of infinite parallel universes never made sense to me (except as very creative sci-fi).
about 1 year ago
Actually no matter if someone doesn’t know after that its up to other users that they will assist, so here it happens.
about 1 year ago
I just got done reading an article from discovery magazine written in 2010, that tried to explain time travel not being possible via a “closed time” method.
I’d have to say, while the concept of time travel can and is very strange, I don’t honestly think it is. The simple solution (maybe whimsical, wishful or what not, perhaps there’s more to it?) is the simple theory of the multiverse. At in given point in time, there are an infinite number of possible outcomes, and each outcome happens infinity. Maybe it’s me, but giving it some thought, it’s the only possible way (or at least the only conceivable way by me.. there may yet be un/inconceivable methods beyond our perception or understanding).
Imagine if you spent one day building a gate that would take you one day into the past, and after building it, walked though. Since you didn’t see you’re self walk through, it didn’t happen.. at least not in this version of the universe. But since you did, it clearly did happen.. you appearing then, in another version; already created or created at that moment, I can’t even begin to conceive.
But you do walk through, and there you’re past self is. Should you decide to take the risk and kill yourself (I don’t want two of me, I doubt it would work out well), you would simply being killing the you in that time frame. you would still be you, from your own time; you would be you, simply one day older in reference to your current times view of you. Should the opposite occur, and you sense the hatred for yourself in your own (future self’s) eyes, and kill him, well.. you killed the person from another time line.. no damage to your own line, either way.. I always think back to Sliders [pre loss of the original cast] and thought that had a good grasp on it.. but these are just my thoughts.. maybe another me has a better explanation for ya ;p