Time Travel in Fiction Rundown

And thanks to my friends Sam and Niko (and all the rest) at the Corridor Digital channel for making awesome videos.

For ages I’ve been thinking about doing a video analyzing time travel in fiction and doing a comparison of different fictional time travels – some do use wormholes, some relativistic/faster than light travel with time dilation, some closed timelike curves, some have essentially “magic” or no consistent rules that make any sense, or TARDIS's, or whatever. This video is an explanation of how time travel functions in different popular movies, books, & shows – not how it works “under the hood", but how it causally affects the perspective of characters’ timelines (who has free will? can you change things by going back to the past or forwards into the future?). In particular, I explain Ender's Game, Planet of the Apes, Harry Potter and the Prisoner of Azkaban, Primer, Bill & Ted’s Excellent Adventure, Back to the Future, Groundhog Day, Looper, the video game “Braid”, and Lifeline.

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[thatxmas]

An entire video on time travel without using the word 'paradox'. Congratulations.

[SilverZeruel]

I wish there was a second part of this, with Avengers Endgame, Tenet, Dark, and Umbrella Academy included.

[rhyanbennett]

Me: “So, Doctor Who, which time travel mechanism will you use?”

Doctor Who: “Yes.”

[dwilborn]

I really liked the arrow charts as a visualization tool. I also realized that Doctor Who's chart would essentially be a scribble to our eyes.

[leoseek]

"Harry potter time travel is perfect because nothing is changed"
Cursed Child: "Allow me to introduce myself"

[thingsareabouttogetgrusome]

Cursed child isn’t accepted as:

a) an actual Harry Potter book
b) a well written book
c) consistent with prisoner of Azkaban time turner logic

“Cursed child sucks” -literally everyone

[Real_MisterSir]

It's also equally interesting in the Harry Potter type time travel, that the time traveler effectively has no free will over whether they will commit to the time travel or not. It is their fate no matter their conscious thoughts, they will perform the action. And that also ties in well with the HP universe's use of prophecies, which also imply that free will to a certain extend is blurred. Potentially free will exists, but all thoughts and decisions will still lead to the same outcome - like throwing a stick in a stream - Its path down the stream may be random, but it is a certainty that it will flow down through it one way or another. It is confined chaos.

[Cressxlia]

I think Steins'Gate is really worth talking about as it has an interesting concept of how time travelling works in their timelines.

[frubge]

Can’t wait to see “Time Travel in Non-Fiction”

[claudialej]

the time machine is pretty good too! it was built for the purpose of saving a loved one but the inventor can never save her from dying because her death is what led him to build the machine to begin with, so he can't be there if she doesn't die

[absolutelynot]

Everyone else is talking about different forms of time travel in media and I'm just here to point out he drew a tail on the apes at 1:00

[shellnut]

The game Outer Wilds has probably my favourite depiction of time travel ive seen recently (huge spoilers, go play the game first)
















Similarly to Groundhog Day, the main character seemingly relives the exact same 22 minutes over and over again, retaining all their memories of past loops. We find out later in the game that there is effectively a time machine linked to the main characters brain that is repeatedly sending our own memories back in time 22 minutes to their past self, creating the illusion of a time loop where in reality they have consious memories of things they have not done yet.

[connorjames]

Steins;Gate has the most creative version of time travel I've ever seen in a fictional setting and I hope you analyze it sometime in the future!

[meharthakur]

*Alarm rings: 7am*

*Snooze the alarm*
2 minutes later

*Looks at watch*

*11am*

I am a time traveller

[Fregmazors]

I'm glad you touched on how cool the time travel in Prisoner of Azkaban is. It really seems like the only logical way it could work. You can't go back in time to kill your grandfather, because you didn't. Although that's hard to accept.

[aneonfoxtribute]

One of my favorite examples of time travel, and in my opinion the best example of time travel, comes from Steins;Gate.
There are three methods of time travel in Steins;Gate: D-Mail, Time Leaping, and physical time travel.

With a D-Mail, you send a text message through time, which has the possibility of changing the past. If the change isn't big enough, then functionally nothing will change (for instance, if the thing you tell someone to do is minor or if they just ignore the text), but if it's big enough, you can change a lot. This is a large part of the plot, the characters sending text messages to the past and it enacts huge changes. For instance, in the story, someone plans to leave, and you send a D-Mail to them telling them to stay, and they will which causes massive changes. Nobody remembers anything from a D-Mail except for the protagonist Okabe.

With Time Leaping, you mentally jump back into your past body from the future. You can only jump back 72 hours, and obviously because of this restriction you can only jump back three days before the machine was created. The person who uses the machine remembers everything, and the timeline changes just by virtue of your future knowledge. If someone other than Okabe were to use it, however, Okabe wouldn't notice any timeline change under normal circumstances, unless whoever it was did something so big that it forced the timeline to change. But time leaping itself wouldn't cause the timeline to change on its own, it's what the Leaper does with the future information that would cause it to change,

With physical time travel, it's exactly what it sounds like. You travel back with your physical body. No changes are enacted on the timeline because the timeline already takes into account the fact that you have/will travel back in time, like Harry Potter.

All of this revolves around the Worldline system. Every change made to the timeline takes them to a different Worldline. These Worldlines are shown on a little device that shows you exactly what Worldline you're in, but for the most part only the numbers after the decimal point change. To change the ones place of the device, that requires an absolutely massive change, one large enough to change the entire trajectory of the world. However, the worldlines revolve around several points that happen no matter what. No matter what you change, no matter how you turn back time, there are several points in history that will always happen no matter what. The main plot of the story is that one of the characters is fated to die by the worldline, and Okabe's attempts to save this person's life in the completely fucked up timeline that he inadvertently made, requiring him to revert every change he made in the story. Fate literally contrives this persons death. Even if Okabe does everything perfectly and gets this person in a position where they cannot possibly die even by mistake, they'll just drop dead with no discernable reason. It's SUCH a good example of time travel, and it manages to prevent paradoxes perfectly by just saying "It's another Worldline!".

[nerdherd]

[paraphrasing] “in Harry Potter time travel, what you do doesn’t change the timeline, it just results in what already happened”
*cries in Cursed Child*

[lynettepettitt]

Groundhog Day was supposed to take about 30yrs of reliving the same day... It's no wonder the character tried to kill himself a few times

[seraphimboys]

My favorite kind of time travel is primer, bc it’s the most realistic imo. Time travel would get messy and horrible if it were to ever exist

[adelineg]

My favorite time travel is from The Five Kingdoms series by Brandon Mull. After traveling back in time, you’ll find that the thing you thought you’d changed had actually always happened. In other words, it’s like Harry Potter’s time travel, except with one key distinction: you cannot travel to a time when you already existed, meaning that you can’t travel to the same time twice and can’t travel to any time that you were already born.