The Marty McFly Problem. in Whey and Sonic Screwdrivers.

So I was saying to someone, “Doing the same thing twice and expecting the same results is a sign of retardation, unless you understand quantum mechanics. And I don’t understand quantum mechanics, though I do have a small grasp on temporal mechanics…”

Okay, I actually didn’t say that to anyone. I can’t be the only one who does head-conversations, pretending to talk to someone.

See, sometimes when I can’t sleep, whether it’s morning or evening, my mind wanders to memories. Woke up maybe 45 minutes ago, and naturally started recounting my final dream, which is usually the most vivid. If I focus enough, sometimes I can “reenter” that dream, which is fascinating. Alas, I woke up with an erection; morning wood typically correlates with me having my final dream of the night, and being unable to fall back asleep.

Now, I’m not even talking about recent memories. This time I was recalling memories from high school AGAIN. And regardless of memories, it sometimes gives me that feeling of “I can never go back again”.

Which isn’t fun. So rather than wallow in morning sadz, I switched my train of thought. Kind of thinking about my direction in life.

And I because I thought of temporal mechanics, I thought of Dr. Erin MacDonald, phD in Astrophysics.

She could give a crash course in the various types of time travel without preparation. And I’m not as smart as her to remember much beyond the basics.

Which got me thinking about how convoluted “Back To The Future” is. Trust me, I’ve seen 45 minute video essays that still had me going “this is a clusterfuck, and not of the Mongolian variety”. Now, I’m not drawing out the entire timeline, as it is waaaay more complicated than you think it is. To start, I’d like to just focus on Marty in the first movie.

Quick terms: predestination paradox, and branching timelines. I much, much prefer branching timelines, as tight predestination paradoxes are very, very difficult to write and make sense. In a predestination paradox, there is only one timeline, and if you go back in time, you were always meant to go back in time - and already did. Branching means that if you go back in time, merely being there means you’re in a different timeline that branches away.

It’s obvious this is not a predestination paradox. As in, Marty was always destined to go back in time. This is because he changes the future. Beyond his ENTIRE FAMILY CHANGING, and him now having a nice car, the act of knocking over a single pine tree changed the name from Twin Pines Mall to Lone Pines Mall. (You know, the JCPenney lot.)

I’m going to assume you’ve seen the damn movie, so. Let’s call our first Marty Marty-A. (Thinking of terms past Marty Prime gets dicey.) Marty-A goes back in time, has to avoid banging his mom, and gets his dad to finally bang his mom. Cool. Timeline “restored”, beyond all the little things he did along the way. He’s already altered the past, so consider his parents Mom-B and Dad-B. These aren’t his prime universe parents already.

Marty-A gets back in the Delorean and begins his transit to the future. What’s seconds for him is years for everyone else. Mom-B and Dad-B bone and create… Marty-B. In the future, Marty-A sees Doc-B* “killed” as Delorean-B gets sent to the past, presumably with MARTY-B in it.

*Remember, Doc-A was killed earlier in the film, and by going to the past, Marty already alters the past’s Doc into Doc-B.

So. Marty-B goes to the past. In this timeline, Marty-A is also in the past.

Do you see the problem here?

What does he do, murder Marty-A with a weapon Christopher Lloyd gave him, and then take his place?

Or do the two Martys work together and both go to the future where Marty-C is sent back in time and…

Is it possible in this universe to have an infinite number of Martys in this cycle? Which would thus prove time travel to the past is impossible. (Given time dilation, going to the future just requires the lack of presence of a gravimetric field, for lack of knowing the right terminology. Just know people on the space station are aging slower than us. Slow it down enough, and they’d just be floating up there watching years or centuries go by. Think about it.)

Now, that’s fun to think about, but here’s a gaping plot hole. Back to the Future Part II: The Quest for More Money. Going forward in time seems easy, what’s the issue? You’re going to your own timeline. We do it all the time when we sleep. I did it last night, I went to sleep and WOKE UP IN THE FUTURE!

Marty-A goes into the temporal vortex (or whatever) and ends up in the future. Okay. So. His parents call him for dinner. Where is he? He’s not there. He left for the future. Do I need to say it? Marty shouldn’t be in the future. If you go to the future, you won’t be there. Because you removed yourself from the timeline. Time would just go on without you.

If you try to explain this, it gets really really messy. It’s a plot hole, plain and simple. A good example of going to the future and being removed from the timeline is Futurama.

If you say about Marty, “Well, he met himself, because he went back and continued living.” Yeah, and he’d remember what he saw. Which starts his infinite loop where Marty-A sees himself in the future, remembers it, and alters his path. So when Marty goes to the future, he’ll see the things he changed. And when he goes back, he alters the future. So when he goes to the future.....

Do you see how this is REALLY REALLY MESSY?

So yeah, this is what I think at 5:15 am after a restless night of sleep in order to relax myself. How are you?

Last updated December 15, 2021