
Actually, Marty Didn’t Go Back to the Future: Graphing the Train Scene of BTTF3 - ddcarnage
http://blog.francoismaillet.com/marty-didnt-go-back-to-the-future
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ant6n
Well I saw the movie, and Marty did make it back to 1985. The problem is that
the analysis assumes that every second in the film corresponds to a second in
real life. That's not true, the shots overlap in real life but are shown after
one another in a sequence to make showing what happened (possibly at the same
time) more practical. This overlapping is often used in dramatic
representations of real events in movies.

One hint is when the author notes that acceleration happens much more quickly
during the few short shots when the speedometer is visible, i.e. the
acceleration is much quicker compared to the assumed linear acceleration in-
between those shots.

It would be an interesting project to analyse the sequence of shots and figure
out which ones overlapped by how much, to make the
time/distances/accelerations work out. [Edit: copyediting]

~~~
ddcarnage
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 of it not, for them to reach the 88 mph in under 3
miles, probably a lot of it would need to be non-RT, which didn't feel right
to me based on the way it's presented in the movie.

Totally agree it would be awesome to be able to figure out what overlaps.
Thanks for the comment!

~~~
ant6n
;) 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](https://youtu.be/DPXG4pdPj4w?t=20s)

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soylentcola
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 :)

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justinator
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](https://www.youtube.com/watch?v=Z1PCtIaM_GQ)

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yason
While I've grown with people who spend their after-cinema time analyzing how
realistic the film was, and do acknowledge it can be fun to some extent, it's
just refitting the art into a whole another game and that's by definition
completely unfair. It's like writing a car review of the new Toyota Yaris and
complaining it doesn't handle well on a race track.

The art of cinema is to pull people inside in a story that is generally mostly
fiction. It's like deception by definition: you only offer the viewer enough
pieces of an alternate reality to help his imagination get started and do the
rest. The point of that exercise is to tell a story, and pulling the viewer
into the reality of the film is just a tool in presenting that story. There is
no point making the film's reality more realistic other than to be able to
suggest it to the majority of viewers as a plausible setting for the story.

The train scene is a typical timed action scene. It's enough to repeatedly
show an increasing velocity reading, similarly to how you might show a
countdown timer in a bomb-defusing scene. The point of flashing those gauges
or numbers every now and then during the scene is to increase excitement and
tension, which I'm sure the original author well understands. Assuming the
movie is in wallclock time _could turn out to be_ a fun exercise but in this
case it did not because the timing analysis just ended up pointing out an
irrelevant detail in the movie that was never even designed to be coherent.
So, the discovery is not fun in itself, it doesn't add anything to the movie
experience, and thus wouldn't really be worth much attention.

~~~
Houshalter
Is anyone really criticizing the movie for this? Did anyone really expect
these minor details to be realistic and accurate?

I don't think anyone is upset over this. It's just a fun exercise.

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Animats
Actually, there is no way Sierra No. 3 could take a curve at 88 mph as shown.
It's not a power problem. 19th century 4-6-0 designs are unbalanced and prone
to derailment. There's a solution to that involving a complex suspension, but
that came later.

More than you ever wanted to know about locomotive suspensions.[1]

[1]
[https://books.google.com/books?id=1A4iiGAz628C&pg=PA62#v=one...](https://books.google.com/books?id=1A4iiGAz628C&pg=PA62#v=onepage&q&f=false)

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monochromatic
This is a fun exercise, but...

> we assume events occur in real-time

this is completely unwarranted and invalidates the rest of the analysis.

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ddcarnage
I address this in answer to ant6n's comment.

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ArcticCelt
...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. :(

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amelius
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 :)

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dspillett
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).

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amelius
This analysis doesn't address the fact that the flux capacitor on board
twisted the rules of physics locally :)

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adam12
There is also no way he could have met himself in the future.

Edit: Unless the time machine was capable of visiting parallel universes.

~~~
serge2k
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.

~~~
jkarneges
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 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.

A parallel universe seems like the only way for this to work, despite adding a
bunch of extra complexity. It also conveniently allows old Marty to be unaware
(to some extent) of young Marty's visit, because old Marty would have lived a
life where he didn't take that trip.

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morganvachon
> 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.

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jonnathanson
_" 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.

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serge2k
> 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?

~~~
icameron
Was it working? I always thought Mr Fusion was damaged along with the time
circuits when the Delorean was struck by lightning.

~~~
awalton
The Doc specifically mentions that Mr Fusion only powers the time circuits,
not the rest of the car. So to get Back to the Present it would have had to
have been functional, given the plutonium system was removed between BTTF1 and
BTTF2.

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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 ...

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ant6n
Well, relativity tells us there are no preferred reference frames. But I
believe relativity also tells us that time travel is not possible.

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NickHaflinger
There are more plausible depictions of travelling through time out there than
using a DeLorean travelling at 88 mph. Take Primer for instance:

"Primer (2004)"
[http://www.imdb.com/title/tt0390384/](http://www.imdb.com/title/tt0390384/)

