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Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

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Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#31

Post by NickHaflinger »

Enough all ready with this 88 mph requirement before the flux capacitor is activated. All they have to do is point the DeLorean east and the rotation of the earth will do the rest. Not to mention the earths orbital speed round the sun, the suns trajectory round the milky way and the milky ways trajectory in relation to the inertial reference frame, that's about 1.3 million miles per hour in the direction of Virgo.

Besides why didn't old-doc just post a letter to future-doc and get him to bury some plutonium in the desert in the past. Then old doc goes and collects the plutonium and goes-back-to-the-future and collects the letter and goes back to 1785 and burys some plutonium in the desert, then goes-back-to-the future .. my brain hurts ...

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#32

Post by toothbrush »

serge2k wrote: post #3

> it’s a shame Doc didn’t equip the Delorean with Tesla electric motors when he visited 2015. That would have made things easier considering the Delorean was equipped with a working Mr. Fusion generator in 1885 He put flying car parts into it. Why the hell would he want some lousy electric motors?

> He put flying car parts into it. Why the hell would he want some lousy electric motors?

I think the author is referring to the fact that then the Mr. Fusion could also have powered the vehicle while driving around on land. Perhaps flying would still be impossible without magical alternative-2015 fuel/parts, but at least you'd be mobile on land in almost any situation.

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#33

Post by morganvachon »

jkarneges wrote: post #19
serge2k wrote: post #4

Earlier quoted context omitted.

Why not? 1. Marty leaves timeline to go to 2015 2. Marty meets Marty-F in the 2015 3. Marty returns to 1985 and grows up to be Marty-F. Of course this means that he knew, but that's okay.

The problem is that once he leaves 1985 to go to 2015, from everyone else's perspective he would have effectively disappeared. He (and Jennifer) wouldn't be around anymore to grow up and have a family, so there'd be no future Marty or Jennifer to visit. At most, Marty could visit his parents, who would have continued to exist the whole time and would be pretty shocked to see him after he went missing for 30 years. In…

> In order for Marty to go to the future and see himself, he'd need to continue to exist in 1985 somehow. I'm not sure how to reconcile him getting into the DeLorean with Doc and yet simultaneously going back into his house to live the rest of his life normally.

This is something I've mentally struggled with since the second film came out. His leaving 1985 temporally is an exit event; he ceases to exist in his own timeline. The only explanation I could come up with is that he does indeed visit an alternate timeline where Doc never created the time machine and therefore Marty never goes back in time to "fix" his father's resolve. There are hints about that; Old Marty is still unsure of himself and allows his boss to run all over him, his son took on his and his father's bad traits, etc. The only way this works is if Doc is unable to visit the same timeline going forward, and can only do so going backwards. The problem becomes, if every forward time travel event leads to an alternate timeline (as is necessary for existential reasons), and any changes made to his own past timeline also cause a new timeline to branch off, why is Doc so worried about fixing the past in order to fix the future? They aren't his past and future anymore, just ones he created by traveling through time in the first place.

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#34

Post by dspillett »

amelius wrote: post #29
ArcticCelt wrote: post #10

...but considering that they only need to fall from an height of 258.88 feet to reach 88 miles per hours Marty most likely did made it to the future! Unfortunately he then died instantly by hitting the the bottom of the ravine once he arrived to 1985. :(

But because of the rotation of the Earth and in fact the whole Galaxy in the meantime, the vertical component of the ravine became the horizontal component of the road :)

If we assume time travel is possible which is quite a leap already, why do people fixate on things things having to keep their fixed point in space relative to... well.. relative to what? Frames of reference can really complicate this.

Perhaps time and gravity are related in a manner that means as an object travels through time it maintains position relative to gravitational influences (and local ones affect it far more than others due to the inverse-square relationship) and maybe the effect is strong enough on each part of the travelling body that it maintains orientation relative to those gravitation influences too (so the car not only stays on the road but conveniently wheels-down as well).

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#35

Post by hawkice »

thaumasiotes wrote: post #17
hawkice wrote: post #14

Earlier quoted context omitted.

A good possibility, but Back To The Future's time travel doesn't require 'immediate' consistency. Could be that changes are propagating at 2†, so Marty can meet his future self and watch him fade into a future self that is experiencing his present choices. † Because the propagation would be occurring in sec/sec, the units cancel, so it's just a number -- I jest, those aren't the same 'seconds' unit, you you see the p…

Wikipedia would have you believe that "parts per million" is a dimensionless coefficient, by a similar argument. It's not true; for example, grams of gold is not the same unit as grams of seawater.

Indeed, their argument is belied by the old intro to Chemistry technique I learned -- start with what you know, and keep multiplying by 1, or things that are true expressed in fractions, like 3.28m/ft, stuff like that. That example fact is context-less (although it has dimension), but most aren't, so it's not "gram" as a unit, but "gram of gold in solution", otherwise you will get completely screwed up (particular if you don't specify "in reagent X" as part of the unit context -- wowzers the errors can jump out at you pretty quickly).

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#36

Post by hawkice »

icodestuff wrote: post #18
hawkice wrote: post #14

Earlier quoted context omitted.

A good possibility, but Back To The Future's time travel doesn't require 'immediate' consistency. Could be that changes are propagating at 2†, so Marty can meet his future self and watch him fade into a future self that is experiencing his present choices. † Because the propagation would be occurring in sec/sec, the units cancel, so it's just a number -- I jest, those aren't the same 'seconds' unit, you you see the p…

Substantially faster than 2, but somewhat inconsistently. Marty's brother started fading after only 9-10 hours. Marty doesn't start fading until nearly the week is gone. Old Biff starts fading after an hour or so? The tombstone fades immediately, and the matchbook and newspapers change within a few minutes of Marty stealing back the almanac for the last time, or possibly immediately after it's burned.

The more I consider this the less it seems like there even IS a rate of propagation, because if it was _only_ sec/sec delays then things would change instantly, not fade in and out.

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#37

Post by soylentcola »

ant6n wrote: post #16
ddcarnage wrote: post #8

Earlier quoted context omitted.

OP here. You're probably right it's not all real time. I figured it wasn't completely unreasonable to treat it as such because when you watch it, most of it does feel RT and we pretty much see everything that happens in an uninterrupted way. But for the sake of argument, even if the analysis is skewed a bit, it does suggests they were missing a lot of tracks. So if some of the sequence can be considered RT and some o…

;) A classic example that exaggerates the different passing of time of movie vs real time happens in Monty Python and the Holy Grail: https://youtu.be/DPXG4pdPj4w?t=20s

Went to school for video/film production and time compression was the subject of a couple of fun projects. In TV and movies, you rarely see things in "real time" unless it's specifically done for an effect (like the gimmick of "24" or to create some level of tension).

Normally, you compress time to a greater or lesser degree because you just don't need to see every single action that someone takes in the course of a given hour or event. Like you point out in the Python clip, you wouldn't normally shoot the entirety of a guy running across a long field. You'd show him start running, cut to a closer shot with him making progress, cut to the person/place he's running toward for reaction or to re-establish the destination, and then cut back to the guy as he's getting there.

When you drag these kinds of things out, it can be a good gag because it's almost like a bad storyteller who includes every irrelevant detail. It makes us uncomfortable and throws off timing. In a more tense scene, time is often screwy because maybe you want to drag things out and show all of the characters' reactions to create anxiety and the feeling that "they'll never make it".

Anyway, thanks for the reminder about the Python bit. Always makes me smile :)

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#38

Post by jonnathanson »

morganvachon wrote: post #33
jkarneges wrote: post #19

Earlier quoted context omitted.

The problem is that once he leaves 1985 to go to 2015, from everyone else's perspective he would have effectively disappeared. He (and Jennifer) wouldn't be around anymore to grow up and have a family, so there'd be no future Marty or Jennifer to visit. At most, Marty could visit his parents, who would have continued to exist the whole time and would be pretty shocked to see him after he went missing for 30 years. In…

> In order for Marty to go to the future and see himself, he'd need to continue to exist in 1985 somehow. I'm not sure how to reconcile him getting into the DeLorean with Doc and yet simultaneously going back into his house to live the rest of his life normally. This is something I've mentally struggled with since the second film came out. His leaving 1985 temporally is an exit event; he ceases to exist in his own ti…

"why is Doc so worried about fixing the past in order to fix the future? They aren't his past and future anymore, just ones he created by traveling through time in the first place."

Is it possible that an inventor brilliant enough to have built a time machine doesn't subscribe to the parallel-realities hypothesis, and is unaware of how his invention really works? We'd need to answer this question to get to why Doc Brown cares so much.

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#39

Post by ant6n »

NickHaflinger wrote: post #31

Enough all ready with this 88 mph requirement before the flux capacitor is activated. All they have to do is point the DeLorean east and the rotation of the earth will do the rest. Not to mention the earths orbital speed round the sun, the suns trajectory round the milky way and the milky ways trajectory in relation to the inertial reference frame, that's about 1.3 million miles per hour in the direction of Virgo. Be…

Well, relativity tells us there are no preferred reference frames. But I believe relativity also tells us that time travel is not possible.

Re: Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3

#40

Post by justinator »

soylentcola wrote: post #37
ant6n wrote: post #16

Earlier quoted context omitted.

;) A classic example that exaggerates the different passing of time of movie vs real time happens in Monty Python and the Holy Grail: https://youtu.be/DPXG4pdPj4w?t=20s

Went to school for video/film production and time compression was the subject of a couple of fun projects. In TV and movies, you rarely see things in "real time" unless it's specifically done for an effect (like the gimmick of "24" or to create some level of tension). Normally, you compress time to a greater or lesser degree because you just don't need to see every single action that someone takes in the course of a…

This is also something used in fight scenes, where a person will say, throw a punch, then the camera angle shifts, and the person will be seen to throw the punch again - "The Asian Cut" [0]

[0] https://www.youtube.com/watch?v=Z1PCtIaM_GQ

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