Back to the Future paradox

[Ezekiel T Bluff]

I started playing Back to the future I bought on GOG, and I started thinking about the movies.

Back to the future are among my favorite movies of all time, the only thing that realy bothered me was a paradox in part 2:
When Doc and Marty go to the year 2015, old Biff steals the Delorean, then goes back to 1955 to give the almanac to young Biff, then comes back to the 2015 and leaves the car. The thing that bothered me was: if Biff changed the future, creating an alternate future, he should have returned to the alternate 2015, and not he original one from which he started.

I realize that if Biff never got back in the original 2015, Doc and Marty would not have been able to go back to the alternate 1985, because they wouldn't have the time machine, but still...

Most ilogical...

Can someone think of a way to explain this paradox?

 

[Zack Alklazaris]

Can someone think of a way to explain this paradox?

Well... the only thing that I really can say to explain this is shown only within the Back to the Future Universe.

I noticed that the timeline of BttF is not instantly affected by an event. Event changes take time to process through out the timeline and when they do, they ripple. This is shown by BttF Part 1 where Marty's siblings are disappearing in order who was born first. This may hold true as I don't believe there was any proof that events had change in Marty's house when he got back until he woke up the next day. Even the little things like Twin Pines Mall changing to "Lone Pine Mall" after Marty took it out falls within this theory because he killed the pine at the beginning of his adventure.

In the same respects Biff gives the book to himself in the past and then immediately goes back to the future. Also the event itself was gradual as it took him a while to acquire that amount of power even with the book.

The only thing that I can recall that would be a bit of a stretch is the fact that Marty got that letter pretty fast after the Delorean was struck by lightning, but maybe it was just enough time as there was some delay.

You want a real problem with Back to the Future, explain to me how the Delorean went into the past after being stuck by lightning when it clearly wasn't going the required 88mph?.

 

[Rastien]

Time travel filled with paradox's and conflictions! well i never If i sit down and pick apart any story that has involved time travel it doesn't become as enjoyable for me so i just suspend belief.

If anything can't be explained it's magic time travel!

 

[Fappy]

At least it doesn't have as many paradoxes as the Terminator movies!

 

[Atmos Duality]

Ah, "sharding".
Nasty ***** of time travel, she is.

Of course, you can't have a time travel plot without creating some sort of paradox, unless the timeline is purely observed, and not altered (though even then, I imagine it would still make those who study chaos theory groan in frustration).

 

[Asita]

Can someone think of a way to explain this paradox?

...From an internal consistency standpoint? No. From a meta-universe standpoint? Easily. Back to the Future was horribly inconsistent with their portrayal of paradox, to the point that at the end of the day the rule regarding time travel is "whatever suits the characters' needs at the time". For instance:

Spoiler: Back to the Future 1

In the first movie the paradox effect was shown to be a slow deliberate process that gave Marty days to fix before it started directly affecting him. This is in turn directly opposed by the nigh-instantaneous fix that occurs when his parents officially ge together. For added confusion, by the time the paradox actually started affecting him, they'd already been well down the very path that Marty needed them to be on in order to exist. They play it a diferent way with his return to the future, as he finds that his more subtle changes have altered the timeline to a degree, without his knowledge. For bonus points, the film also creates a 'stable time loop' by having Marty essentially create the song Johnny B. Goode.

This very plot device is revisited in later films, with different results.

Spoiler: Back to the Future 3

In Back to the Future: Part 3, the picture as a plot device is revisited, showing Marty his own grave. Instead of the slow, deliberate change in the first movie, however, the tombstone in the picture shows instant change multiple times in the story (removing Doc Brown's name, adding "Clint Eastwood" and ultimately removing the tombstone altogether). This is again later revisited with the "You're Fired!" fax Jennifer took from the future, which changes immediately after Marty refuses the street race. Jennifer herself represents yet another take on the paradox mechanic, as Doc Brown's comment that the alternate timeline will change around her in Back to the Future Part 2 is ultimately vindicated by Part 3's denoument, showing her to be completely unaffected by the changing timeline. Mind you, this portrayal works against Future Biff returning to the future he left from.

On a similar note:

Spoiler: Back to the Future 2

Back to the Future: Part 2 shows a similarly instant effect when Marty burns the Almanac, with the change to the future being reflected on the book of matches he had swiped from the alternate 1985. Oddly enough, the same movie had priorly portrayed Old Biff returning to a future he had just radically changed.

Simply put, Back to the Future's time travel rules are basically defined by what the plot demands of them.

 

[Ezekiel T Bluff]

For the first movie there is a simple explanation for Marty's gradual disappearance from the picture:
Even tough the timeline was changed, for the change to be complete his parents had to fail to kiss at the dance.

 

[Ezekiel T Bluff]

About the tombstones changing instantly:
The same tombstone would be used for anyone who got killed at that moment, so every variable that gets changed changes the name on the tombstone instantly.

About the "You're fired" paper:
This makes no sense, because if Marty didn't race, he would not work at that job, or live at that house, so entire paper should have vanished.

 

[Hawk of Battle]

Can someone think of a way to explain this paradox?

Well... the only thing that I really can say to explain this is shown only within the Back to the Future Universe.

I noticed that the timeline of BttF is not instantly affected by an event. Event changes take time to process through out the timeline and when they do, they ripple. This is shown by BttF Part 1 where Marty's siblings are disappearing in order who was born first. This may hold true as I don't believe there was any proof that events had change in Marty's house when he got back until he woke up the next day. Even the little things like Twin Pines Mall changing to "Lone Pine Mall" after Marty took it out falls within this theory because he killed the pine at the beginning of his adventure.

In the same respects Biff gives the book to himself in the past and then immediately goes back to the future. Also the event itself was gradual as it took him a while to acquire that amount of power even with the book.

The only thing that I can recall that would be a bit of a stretch is the fact that Marty got that letter pretty fast after the Delorean was struck by lightning, but maybe it was just enough time as there was some delay.

You want a real problem with Back to the Future, explain to me how the Delorean went into the past after being stuck by lightning when it clearly wasn't going the required 88mph?.

You basically just described Achrons time travel mechanic there; evenly spaced time waves that propogate changes into the future at a rate slightly faster than normal time. It's as good a mechanic as any I suppose, though there are still holes all over pretty much any time travel series. TBH I wouldn't worry about it.

 

[Asita]

For the first movie there is a simple explanation for Marty's gradual disappearance from the picture:
Even tough the timeline was changed, for the change to be complete his parents had to fail to kiss at the dance.

Except that by the time he started to disappear events had already been set in motion so that that eventuality would inevitably occur. The only interference came from another 1955 resident, so as far as 1985 was concerned, that event should have been a foregone conclusion, as should its follow-up. Effectively at that point Marty fading out made as little logical sense as it would have if he hadn't touched his parents history and started fading out when Loraine's father hit George with his car. It's ancient history as far as Marty's concerned and thus not a danger to him.

About the tombstones changing instantly:
The same tombstone would be used for anyone who got killed at that moment, so every variable that gets changed changes the name on the tombstone instantly.

Mmm...you just described the reason for the change itself, not the speed. And it's the speed that's the most noteworthy bit of this, due to how it relates to other changes in the franchise. Recall how quickly the tombstone picture changed in Part 3. Now recall how quickly the family photo changed in the first movie. That's the inconsistency.

 

[Redlin5_v1legacy]

SNIP

I suppose this is as good a defence for the logic of him reappearing on the original timeline as any I could think up. It's just a plothole made necessary by the fact that there was only one time machine in the equation.

 

[Asita]

SNIP

I suppose this is as good a defence for the logic of him reappearing on the original timeline as any I could think up. It's just a plothole made necessary by the fact that there was only one time machine in the equation.

Want the best part? Deleted scenes indicate that Old Biff was erased from the timeline after he returned to the future, or at least was originally intended to.

 

[Relish in Chaos]

SNIP

I suppose this is as good a defence for the logic of him reappearing on the original timeline as any I could think up. It's just a plothole made necessary by the fact that there was only one time machine in the equation.

Want the best part? Deleted scenes indicate that Old Biff was erased from the timeline after he returned to the future, or at least was originally intended to.

Yeah, either because he hit himself in the chest with his cane after he yanked it free from it being stuck in the floorboard of the DeLorean, or he was shot and killed in 1996 by Lorraine after she got fed up with Rich Biff's abuse.

 

[Asita]

Want the best part? Deleted scenes indicate that Old Biff was erased from the timeline after he returned to the future, or at least was originally intended to.

Yeah, either because he hit himself in the chest with his cane after he yanked it free from it being stuck in the floorboard of the DeLorean, or he was shot and killed in 1996 by Lorraine after she got fed up with Rich Biff's abuse.

That makes absolutely no sense. The sheer impossibility of the latter nonwithstanding (given that Old Biff appeared in the unaltered timeline), both of those explanations simply entail death and do not explain why Old Biff was actually fading out in that scene.