I’ve never though of there being nothing there once you went back in time, but it does make a lot of sense. I see two ways that your explanation of time travel can still allow you to see stuff after you go back. I’m not so much trying to find a theory that makes the most sense, but find one that is at least theoretically possible so that science fiction stories can work.
In the one that I put on the Grandfather paradox page, I see the ’60 years ago universe’ as moving through time at a rate of 1 second per second just like us. So, after killing my grandfather in universe B when it is t=1946 and my universe is t=2006, all of the universes between those two and behind t=1946 are normal. If I live my life for 40 years, so my universe is t=2046, then in the meantime universe B has moved forward 40 years, there is a 1986 in which I don’t exist. I’m not sure whether the years in-between 1946 and 1986 would be different, I can see it work either way.
The other theory I can think of that might allow for the classic sci-fi time travel (I’ll also put this on the Grandfather page) is if particles actually have a length in the t dimension. What if atoms are 100 years long in the t dimension and we are experiencing the front of them? Then you could go back 99 years and see the world around you. It doesn’t matter that the particles have moved in 3-dimentions since then; in the t dimension they are all still moving at a constant speed with each other. In this case, you could create a time travel paradox by moving (in 3-dimentions) particles in 1905 that are in your body or will effect your body in 2006. The big problem with this one is how the particles in your body exist in 1905 twice. Maybe they “bend” back, or maybe when you go back 99 years, your whole mass dose, so in 1805 there is empty space with nothing but the scattered particles that will one day make up your body. -arctic gnome 18:28, 26 March 2006 (UTC)