Ummmm…..

That’s got you baffled hasn’t it?
Keep it a secret, but actually my time machine is made to look like a normal domestic fridge with a self- closing door. (Private joke. Don’t ask!) – Keith.

or–there may be an infinity of alternative universes, and a person may take many many paths through them, including one that didn’t involve doing away with one’s grandmother.

Sort of a variation on “He’s his own Grandpa”.

Well I did think about saying that I met this beautiful woman in 1913 and slept with her, only to find out in my own time that she was my grandmother. Would that be incest? – Keith.

All the time machine theories are just that, of course. Theories. Comic books in particular like playing with them.

There is the “time loop” aspect looming large, of course. Let’s say that in 2011, I get in my time machine and go back to 1865 to prevent the assassination of Abraham Lincoln. I succeed. He doesn’t die. The new “reality” is that I grow up in a world where Lincoln was never assassinated. So… I would have no reason to go back to 1865, right? Lincoln, without my interference, is murdered. And the cycle would continue, ad infinitum.

Most comic books used to state “You can’t change the past.” (Well, other than injecting yourself into it, I suppose.) That would mean that — as in your example — your presence would not — could not — have caused your grandmother’s death. Period. So even if you planned your visit to fulfill a specific task, the Fates would do something… anything… to keep you from doing it.

Later, the comic writers played with things a bit more, and many amended it to say that you can’t affect your own “reality,” but your actions would create an alternate timeline (as Sue mentioned). So in your example, there would be a reality in which your father and you never lived. But the “you” from “your” reality still exists.

I guess we won’t know until someone actually does it.

That is, assuming no one has already, without our knowledge… Heh.

(Let’s hope my comment shows up this time!)

My blog is set up so that first time comments have to be approved. After approval the comments automatically appear without the need for approval. I can also ban people permanently, this is to prevent spammers. I removed one of your comments because the two were identical.

Perhaps the future world will be devastated by wars because Abraham Lincoln had lived? Someone could have gone back in time and arranged to have him shot to prevent it from happening by putting the idea to John Booth and his gang. – Keith.

Tut, that’s what you get for messing about with time paradoxes, don’t you listen to the Dr?

Oh yes, I listened to the doctor. He told me, after my latest brain scan, that I would soon be well enough to be released back into the community. – Keef.

You should go back to just before you set off and warn yourself not to go. The sight of yourself would probably give you a heart attack and kill you.

Problem solved.

That wouldn’t work either. As I stated, if I come back to the present to warn myself I wouldn’t be here (I don’t exist in the present) so I couldn’t go back to to just before I set off.

Er. . . not sure what you meant by “. . .give you a heart attack and kill you”, and “Problem solved.” – Keith.

You would create a paradox and whole universe would explode… of course then you would not have been around to course the paradox so it would not happen. but then you would be around to make it happen but then it would not happen but then it would happen…

Great Scott!

Keep thinking Stu, you’re beginning to understand. – Keith.

If I keep in on thinking I’ll have an aneurysm.

Is that with a twist of lemon and soda? In that case I’ll have one too. – Keith