This season of LOST has got me thinking a lot about time travel. I agree in principal with the way they handle their time travel, namely that when you are back in time you cannot change anything.

So I was prepared to write a large post about my theories on time travel, and then I discovered that it was already completely covered on BaconBach, almost word for word what I was going to write. I guess that means that when I search my own blog to see if I have already talked about something, I better start searching his blog too.

Anyway, you can check that link out to read about it there, or you can read my summarization here (EDIT: I think this ended up being longer than the original, so perhaps summarization isn’t the best word).

If you go back in time, I don’t think you can change anything because anything you would have done back then would have left evidence for us to find in the future. For example, you can’t kill Hitler before WWII because here in the present we all know about Hitler and WWII and they happened. If you had killed Hitler, then we would live in a world that never knew about any of that stuff. So obviously, you didn’t.

Let me give you another example. Right now, as we sit here, we don’t know anything about time travel. But lets say in the future someone invents time travel and goes back in time and leaves a novel there, say a “lost work” of Shakespeare, so that in the future generations of people grow up believing that novel is a work of Shakespeare (thank you Chrononaughts for the plot line). So here in the present day, we have all grown up with this book. We’re taught it in class, we’ve seen the movie version, countless other works have been based off of that book, basically the entire landscape of pop culture has been affected and all of our thinking is suspect.

“But”, you say, “so what? At the moment he placed the book, all of the future that did not contain this book was wiped out and a new one was created in which the book existed.” Okay, that’s possible. But if that were true, then time would probably need to be redone every time any time traveler went back to the past, based on changes they did or did not mean to make. And I’m assuming that if we had a time machine, there would be lots and lots of trips to the past. So whatever mechanism governs the deleting and re-making of time would be constantly doing nothing else than changing our lives. It’s CPU would be pegged out at 100% so to speak. And I just can’t imagine a world whose governing laws would allow for the constant erasing and re-doing of every detail of everything.

There is the possibility that going back and changing something spins off an alternate reality in which that event did or did not occur.  I’m not saying that’s not true, and this doesn’t preclude that. I’m just saying I don’t care because A) if there are alternate realities then I think all possibilities already exist (so you are not creating a new one) and B) who cares what happens to those evil me’s that exist in those alternate realities, I only care about what happens to this one!