I know the Dope has many experts on temporal displacement and I need your help handwaving away the biggest plothole in the Back to the Future trilogy - why Part II should never even have happened. It’s been bugging me for ages
In the first film, Doc Brown’s dog Einstein becomes the world’s first non-Brazilian time traveller by travelling forward in the future one minute. During that minute he has vanished, Marty mistakes this for disintegration. Then he appears as he was, right on schedule.
In the second, Doc, Marty and Jennifer travel thirty years in the future where they encounter their future selves. Eh? Shouldn’t they be missing for thirty years? Einstein didn’t meet a version of him that was one minute older.
But then their future selves would have been aware of this; future Jennifer is shocked to the point of collapse by her past self - she has no idea that she came to future when she was younger, which is something that’s pretty hard to forget.
The dog never went to the trouble of traveling back one minute. That was just a minute he jumped over and was never present to see himself arrive one minute in the future.
I’d have to refresh myself on the movies but I believe this is covered by there being multiple timelines involved. The Jennifer that freaked out over seeing her younger self came from the timeline in which the time-travel did not happen. As a result of learning why his family became pathetic losers, Marty avoided the accident that set that whole future in motion, and the Jennifer of 2015 would never encounter the younger one.
Doc never encountered his future self, did he? In fact, he would have gone to great pains to avoid doing so. When he and Marty went back to 1955 in BttF 2, he did run into his past self, but he was careful not to give him a good look at his face.
A worse one is how did Biff bring the time machine back to Marty and the Doc when he had already changed history? Even if he went back to 2015, it should have been the 2015 of the dark Casino timeline.
The fanwank answer to both of these issues is in the BTTF universe changes in the timeline take time to propagate throughout the timeline giving the heroes time to have the adventure.
The answer for all of these questions is that it’s established that the BttF universe works on slow ripples forward, rather than creating an instantaneous changes. This is made clear by the original movie – the picture of Marty’s family fades out slowly.
So the reason they can meet themselves in the future is because them leaving hasn’t “caught up” in meta-time to the time machine. The ripple-effect hasn’t taken hold yet. Same with Biff. He changed the future with the almanac, but he came to non-Casino 2015 because that time ripple hadn’t caught up yet.
Of course, this raises the question of why Doc Brown wanted them to interfere with a future that may not have happened, but it’s possible he was just playing Ghost of Christmas Future there.
(Not that BttF doesn’t have plenty of time travel related plot holes)
Thanks for the answers, I love Back to the Future as the greatest trilogy in film so ironing out any latent niggles is good for the soul
That’s true, but if he did go back and then wait one minute he’d have the knowledge - if he were human - of travelling into the future then back again, which Marty and Jennifer in the future don’t. That’s why I don’t get years of loserdom rather than them vanishing and reappearing in 2015, although I think the above posited ripple-effect taking time to ‘catch-up’ is the best explanation.
Ah yes, forgot about that. But it wouldn’t explain futureMarty’s cluelessness.
Unrelated tidbit : I recently re-watched Part II, and the scene of Marty walking around the town square in 2015 showed flying cars, holographic movie ads, robotic wait staff, hoverboards, auto drying, auto fitting jackets, auto-lacing shoes, robotic gas station attendants, instantaneous weather reports…and (wait for it)…
It’s always baffled me that people see this as a plot hole. I think it just means that Marty and Jennifer returned to the present day safely.
As for why their older selves don’t seem to remember going to the future, someone pointed out above that Jennifer would have assumed it was all a dream. And Marty, well, his life had turned to shit by that point, and he had probably become hazy on the details of his trip to the future in light of all his problems. Also keep in mind 1985 Marty never encountered 2015 Marty.
At that point in the trilogy he also had not yet gone back to 1885 and gotten the advice from his ancestor Seamus about not reacting to people calling him a coward.
He very well could have remembered it. “Tonight is the night my past self visits!” But Doc would have drilled into his head how important it was not to interfere - his very existence could depend on it.
Thanks for fielding it, but I’ve been making this point on the SDMB since at least 2001. There will always be another thread asking about it. That’s why I have a numbered explanation handy, which covers a bunch of the secondary questions that always seem to follow.
I’m pretty sure that at this point I’ve covered all the alleged time travel holes. The list above handles most of them, but if there are others you’d like addressed, I will dig up my answers for them.
Umm, no, he didn’t. It’s clearly 2015. Note Marty and Doc taking off in the flying Delorean after Biff returned it. And the “I brake for birds” bumper sticker. The filmmakers explained it as Lorraine shooting Biff in the 1985-A timeline, erasing Biff from all future timelines. When Marty restored the original timeline in 1955, presumably Biff returned to existence and continued to live until at least 2015.