Yeah, I was thinking the same thing. We never actually saw Marty completely disappear, so we don't know what would have happened. I was thinking that rather than disappearing, it might have changed to show whatever family Lorraine might have ended up having.
Maybe the photo itself would have disappeared too, like Old Biff did when he caused his own death. We don't know since it didn't finish. The only real mystery regarding photos is Doc's grave. The stone disappeared, which makes sense, but the photo itself still existed. Other than that, changes we saw involved matchbooks and newspapers, which would still exist, but be altered.
This conversation has got me wondering what exactly would happen if we had two things, with the exact same matter down to the subatomic level, tried to exist in the same universe. Would it destroy the universe, would they merge, would nothing happen?
Just guessing, but I think nothing would happen. You're kind of describing the Time Cop effect, which to me makes little to no sense. Let's say you had a pen and took that pen to the past and laid it down next to the same pen. I see no reason why anything would happen.
And I see no reason why it would matter if you had a conversation with your past/future self. Technically, we aren't the same matter either. Cells die and are replaced all the time.
That is interesting. I really don't think the idea of the "same" matter would do anything--we are really only talking about building blocks. But, suddenly the conservation of matter/energy would be upset. Would something of equal matter/energy suddenly wink out of existence or would matter/energy just be created out of nothing?
The amount of matter would seem to be so insignificant compared to the rest of the universe that I can't see the universe caring. The universe is constantly expanding anyway.
I've always wondered what would have happened had Marty actually disappeared then. How would it look to the other people watching? Granted, it seemed like very few people were paying attention to him at that moment, although you'd think that at least a few members of the Starlighters might have noticed. Maybe it would be like in that Doctor Who episode where Rory got erased by the crack at the end of "Cold Blood." Amy kept trying to concentrate so that she would remember him but, the instant something broke her concentration, she forgot him completely.
This is actually something that the movie should have covered. Marty should have asked Doc that question. If Marty does disappear, then he couldn't go back in time and make himself disappear, so we have the grandfather paradox.
Thinking about it, Doc wasn't focused on that at all. The timeline doesn't seem to change instantly to the time traveler. One thought is that 1985 changed to the 1985 Marty came back to instantly, but the changes didn't catch up to Marty in 1955 because he was out of place.
Perhaps because Marty directly affected his own life, that picture would have cycled back and Marty was going to be ok either way, and by doing all he did, THAT changed things.
He would have disappeared, and then reappeared because his disappearance would alter the previous week.
It's an issue the movie didn't cover.
And if Marty's existence was still in doubt at some quantum level at that moment, then shouldn't it also have affected the other Marty from Part II in the same way at that same moment as well?
That's a very fair point. I guess in universe, the answer is no, maybe because Marty was from a timeline where he already saved himself. Perhaps the changes in the timeline are chronological and the Marty from Part II was more in the future so the disappearance issue isn't simultaneous. Perhaps that say Marty from 2015 wasn't affected at all, but Marty from 1977 was already gone.
Given that Marty's issues lasted only a few seconds and George did kiss Lorraine, all was good for Marty II. Since timeline issues are clearly not instantaneous for the time traveler, and since George did kiss Lorraine independently, it seems that even had Marty disappeared, he would have reappeared right away for that reason. That brief disappearance was a blip because the timeline hadn't caught up to him. If that Marty from say, 1977 had disappeared, he was probably already back before the kiss.
I hardly think it makes them meaningless. This time travel story just followed different rules; I'm sure there are plenty of people in the Star Trek universe who could explain why in completely made up Trek technobabble until you stopped asking...
But they didn't explain it, and they never showed the prime universe's fate, which means that there is no reason to treat this story like any other Trek time travel story. What makes a story meaningful are the stakes. If traveling back in time has no stakes, then why shouldn't I do what I want?
Speak for yourself: CBS and Paramount can have my head canon when they pry it from my cold dead hands.
Let's say you apply for a job and don't get it. In your head canon, you did. You're not getting the paycheck. It's nice to think about, and works logically for you, and that's great--but it's not official.
I wish that the Shatner books or the book Crucible Kirk would be canon, but they aren't.
I can accept them, and that's a nice consolation, but it still doesn't affect anything.
