Welcome to Gaia! ::

I thought it might be fun to discuss some things like teories on how time travel could work, how black holes might exist, and other fun aspects of theoretical physics. Personally, I like Neal Asher's take on time travel. In his book Cowl, it elaborates on it pretty well. Vorpal energy, as it's called, is what allow for time travel within a certain radius of earth and its life. The idea is that it takes a certain amount of energy to travel linearly back in time. Now, if you change something, this creates an alternate line that deviates from the main time line. This shoves you down a probablity slope, how far depending on just how much to mess with the time flow, like bringing something extinct in one time to another that it shouldn't be in. Of course, if you do something stupid, like creating the paradox of mudering your own father before conception, you'd be shoved so far down the probablity slope that you wouldn't be able to get back to the main line. Of course, being able to get ot the main line form an alternate line means that it would be possible to travel horizontally in time.

Anyways, just some interesting thoughts I had.

One could look at it that way, but I like to think of it as creating that alternate time line, which once you go away from it, unless you have the secific directions to go to that or another that has been created, you stay along the main line, and try to not alternate it, lest you create a new pobability slope, and if you were to create as large of a change as Hitler winning WWII, you'd go so far down the probablity slope that you wouldn't be able to get back.

I think everything you do (big or small) affects the world around you. For every action there is a reaction. It may not seem like much but you change the whole course of history by changing one detail. Like If Hitler had gotten accpeted into art then there would be no Holocaust or if John Kerry was president we would be out of Iraq now. But there are other consequences that we can't forsee and who says we want to know them. Then there is the paradox that occurs with them like you go back in time and kill Hilter at 20 and your 10 year old lives those years and logically would not have to go kill Hilter because he dead and there is need to do or even know that he need to. So he doesn't creating a beautiful mind boggling paradox.

What do you mean "if" it were possible? We're all time travelers. I'm traveling through time right now. Time travel is possible, but as you say it's only being done forward (that we know of).

Personally, I quite liked the theory from Timeline by Michael Crighton. It was essentially like your second theory - there is a separate universe for every possible outcome of an event (not major events, mind you. Just any change at all). So people didn't really travel through time. They just slid into a universe where it is 1986, for example. They used computers to "scan" the new universe to try to find one that was as similar to ours as possible.

No it isn't. If you The faster you go, the slower time gets.

The human species is only one of many species.
Even if it does not have any affect that determines the course of human history, or anything "dramatic" one would have to assume that if there is an alternate universe or whatever for these 'large' changes (which really don't nessicarily affect much in the grand scheme of things) then there would be for all small differences. It actually makes more sense, if you really think about it. Why would science change significantly to only work with how humans percieve events?

Not really, if you ask my thoughts. That would be a huge amount of energy you would need to be able to make a jump that far downslope, nevermind getting back up it. In other words, you can change the immediate past by going back and doing what one must before you go too far downslope, the event of it being successful being called a short circuit. and everyone involved in the event would have the memory of both the original happenings and the changed ones.

On the idea of different realities. I dont understand how they could exist. The theory has as much proof as god does. And for time travel, this is my prefered website. It explains that we may be able to travle back in time. But it would be impossible to change the course of the future.

http://en.wikipedia.org/wiki/Novikov_self-consistency_principle