Why would you go back in time if we could? If the culmination of your life has led you to a point that you wish you could change, then do so now. But theoretically speaking, if you go back in time and kill your grandfather, a new universe will occur in which from that point on, you never existed. Most say thats what would most likely happen since the other theories are a little more outlandish. You probably won't disappear, but become a no one. Once you go back, things could have change drastically and such and you are now in a universe you never existed and never supposedly went back time. Speculation, but it seems the most reasonable choice.
Well I mean, us as people get older over "time". The sun goes up and down to signify a new day and "time".Thats the way I look at it. Plus if SUPER smart scientist say time travel is possible then I believe them.
You have a direly ill impression of the universe, reality is not a computer program, there is no such thing as time, there is simply what exists now, in order to time travel you would have to artificially replace everything in the condition you are expecting.
This is part 1/5 with Brian Cox, more of an overview of the whole subject of time but some parts are related. [ame=http://www.youtube.com/watch?v=km89X8zoJH0]YouTube - Brian Cox- Horizon- Do You Know What Time It Is?1of 5[/ame] This is him again talking about why the "past is protected from the future" [ame=http://www.youtube.com/watch?v=LfCv9GLwvYE&feature=related]YouTube - Prof Brian Cox on how the past is protected from the future[/ame] There's a youtube video of him talking with another professor about how the minus sign in the equations are what gives the mathematical version of "forward motion" of time but i couldn't find it. This one I think explains time specifically the best in how it's a dimension rather than some intangible thing that is made up so we can visualize it in our minds. [ame=http://www.youtube.com/watch?v=JtMw2f5YJk0&feature=more_related]YouTube - Brian Cox explains the Block Universe[/ame] @grass man420 complicated yes, impossible no (at least not yet). I think that just because I've come to accept that if it's possible in the math then it's almost surely possible in the physical world. Yes there may be changes in the way we do math or some new universal laws that we find later on that prevent it but those things are only found by first believing that it is possible. Also I wouldn't say I'm so sure about it just fairly confident, but this is also coming from someone that's only up to maybe half way of the actual mathematics behind it. It's like going into a dark room and saying you know where all the walls and objects are in a room before they turn on the lights, I'd rather believe that there are things in the room and I just don't know where yet. We can do tests and experiments to find everything in the room and eventually we will have such a strong grasp on the room that we can then try and figure out the color's of the things in the room but we can't say we know the color's before we know enough about everything else. If that makes any sense. You can't answer a harder question without first knowing the basics of the problem and the nature of the things involved, we can only make an educated guess at the solution and so far for time travel the answer is yes but it's ineradicably hard from where we are today. @BagOfHammers Flying was just an example. Think of what people thought back then, sure some saw that birds could fly and thought that we could also but most did not. People had been trying it for centuries before and hadn't gotten it to work yet so why would that change. we know time exists because it has to in order for us to be able to describe our physical universe. We know we live in a dynamic universe and with that it requires that there is a "time" dimension because without it nothing moves. Sure it might not exist in other terms but in the way we have described it it exists. You can describe a glass of water that is half full in several ways, 1) the way I just did 2) that it is half empty of water or 3) that the glass has a barrier half way in that prevents air from going any further. all describe the same thing but are different in terms of the relation is to something else. For math time is the relation of the speed of light (distance light can travel per unit of time), that's why the speed of light is a universal constant everything else is put into terms of that relationship. As for the god part, I'd stay clear of it just because even from the beginning of math and sciences people have been using god to describe the things and actions we don't yet know. Gravity was once called the force that angles exert on objects to keep them in their motions. even today we only have the mathematical version of gravity, which the planets and other bodies don't calculate they just do it by their nature. Math describes what they are doing not why, that is left to religion. /end the crazy long response forgot to add this video he talks about a time and some of the paradox's involved: http://fora.tv/2009/03/19/Ian_Morison_Its_About_Time#fullprogram