eighty eight miles per hour

[gfish]

Today's stupid question: Is the 88 mph trigger for Back to the Future time travel a fundamental part of the process, or is it just an arbitrary limit so that you don't casually violate causality?

I've always assumed it was arbitrary, just another quirky design choice like using a DeLorean in the first place. But then why didn't the Doc bypass it when timing was so critical (in the first movie) or achieving that speed was so difficult (in the third). Maybe ¹⁹⁵⁵Doc couldn't understand the circuitry and ¹⁹⁸⁵Doc in 1885 didn't have the tools. But... it would just be a switch connected to the speedometer. ¹⁹⁵⁵Doc should be able to figure that out. Marty should be able to.

It doesn't make much sense as a fundamental limit to flux capacitoring, though...

Comments

[neuro42.livejournal.com]

I always interpreted it as an inherent limit.

[qarl.livejournal.com]

Just because its an arbitrary, doesn't mean the Doc chose it. It could have been an accident of the engineering, and his understanding of theory isn't strong enough to freely change his actual working effort.

[dagard.livejournal.com]

I kinda figure it's something like this, and that the amount of electrical energy coming off the alternator at 88 mph was perfect for what he'd designed.

[stolen-tea.livejournal.com]

Yeah, huh. That doesn't seem to divide into the speed of light nicely. 1/7620643.52 th is not a particularly meaningful fraction to me...

[slantiness.livejournal.com]

I definitely assumed it was just how time travel worked with the invention. You have to be going that fast. That's just "how it works"

However the plothole that I found in the 2nd movie you could drive a delorean through.

[randomdreams.livejournal.com]

88mph is the speed of sound in the flux of a flux capacitor: any faster and the flux would be pulled out of the cap and it'd arc over, and then all hell breaks loose. You'd have to reverse the polarity of the neutron flow, at that point.

[arjache.livejournal.com]

And of course, any slower than that and it isn't enough to rouse the flux elves from their sleep. Unless you use a hammer.

[blackanvil.livejournal.com]

Patently speed isn't an issue: in the 2nd movie, the car moves in time while standing still, at the end when it's hit by a lightning bolt.

[encapsulate.livejournal.com]

I believe that was a limitation of MacGuffins that were created in the mid 80's.

It can be engineered around, but you would be unable to time travel while retaining your clothes, your boots and your motorcycle.

[dbcooper.livejournal.com]

That makes sense to me. I would guess he probably discovered through trial and error early on that he needed to be moving for any flux to be capacitated at all (!), and then discovered that the Flux Capacitor would only open a time aperture at or above 88 mph (142 km/h).

Of course, in our world, the reason a time traveler using a Flux Capacitor-based time machine would have to reach 88 mph is to make it look cooler on screen. Also, severe tire wear is apparently part of the process, making a DeLorean less than ideal, since it can only carry one full-size spare in its default configuration. I would have used a Volvo XC60 crossover, but they didn't have them in 1985.

[sistawendy.livejournal.com]

Maybe he needed a particular kinetic energy, no more and no less, as one sees in chemistry or quantum phenomena.

[nder.livejournal.com]

I always figured it was chosen because it lit all segments on both LCDs, thereby enabling you to see through time.