WEBVTT

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Magical adventures in fantasy otherworlds 
may sound fun on paper, but more often than

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not they’re a surprisingly risky gamble. In 
the best-case scenario you’ll come back home

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and find only seconds have passed since you left 
and you won’t even get in trouble for being gone.

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Sometimes time passes at a one-to-one rate and 
the whole time you’re gallivanting around in

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the magical otherworld, time’s still passing 
back in the real one and you’re gonna have

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some serious explaining to do if and when you 
get back. But the worst case scenario flips

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that first one on its head - you might think 
you only spent a few days in the otherworld,

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but hundreds of years could be passing in 
reality. The concept of localized time dilation

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is a staple in fiction and folklore because it’s 
frankly deeply unnerving. As a bonus fun fact,

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it’s a real thing in relativity - it’s almost 
totally unobservable under normal circumstances,

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since we tend to stay in mostly one place 
relative to the earth and don’t usually

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move at an appreciable fraction of the speed of 
light, but a clock moving relative to an observer

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can be observed to tick slower than a relatively 
stationary one, and a clock close to a gravitating

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mass will measure less time passing than a 
clock farther away from the same mass. Thanks to

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gravitic time dilation, the core of the earth is 
about two and a half years younger than the crust.

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This is bananas, you may 
remember it from Interstellar,

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that's basically the only time 
pop culture ever used this.

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Maybe those magical otherworlds simply reside… 
close to the event horizon… slowed and distorted

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by the very nature of space-time……… or maybe 
it’s fiction and we don’t need to read too

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far into it. Anyway, today let’s talk about a 
japanese folktale about the dangers of magical

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otherworlds and the importance of following 
instructions from people who know more than you.

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Our story begins with a young fisherman 
called Urashima who’s a very sweet guy

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without a mean bone in his body. His profession 
of “fisherman” does make it a little difficult

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for him to be completely harmless, but he’s very 
conscientious about the whole thing and doesn’t

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do any more harm than he has to. So that’s why 
one day, when he fishes up a massive turtle,

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he remembers hearing that turtles are 
supposed to live for a thousand years,

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and he feels bad about cutting that short just for 
a tasty dinner, so he throws the turtle back and

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settles in for a nice little fishing-boat nap.
This is when a beautiful woman rises out of

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the water, steps into the boat and tells Urashima 
that she was that turtle and is also the daughter

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of the sea god and she’s here because he 
just proved himself in a secret test of

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character and is qualified to be her husband. 
Urashima likes the sound of that, and he and

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the princess sail out to the Dragon Palace to be 
married, where they settle in to live together in

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riches and luxury for a thousand blissful years.
And if only the story ended there. But while

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Urashima is a big fan of this magical palace and 
dragon princess wife situation, after about three

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years of divine marital bliss he starts feeling a 
little bit homesick and he wants to sail back to

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his humble village to check in on his family and 
friends, you know? The Dragon Princess doesn’t

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think this is a very good idea, but she won’t stop 
him, so she just warns him to be very careful,

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because she has a feeling something very bad might 
happen if he does anything reckless. She gives him

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a small box and warns him not to open it under any 
circumstances or he won’t be able to come back.

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So Urashima tucks the box away, grabs his boat 
and sails back home - but it’s not quite what he

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was expecting to see. The mountains and rivers 
are all the same, but the buildings are gone,

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including his house. He flags down a couple 
beachgoers and asks them what happened to the

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Urashima house, and they tell him that’s a weird 
thing to ask, since it’s an old folktale around

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these parts - four hundred years ago some kid 
named Urashima drowned on a fishing trip and never

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came home. His family are, of course, long dead, 
and even the village he lived in has fallen into

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ruin. Urashima realizes the dragon palace might 
just be one of those magical fairy realms he’s

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heard about, where time passes a lot slower on the 
inside than the outside. He thought it was only

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three years, but it’s been centuries out here.
Well, that’s a bummer, but what are you gonna do,

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right? With no surviving friends or 
family and no reason to stick around,

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Urashima prepares to head back - only to realize… 
he doesn’t remember the way. Surprise surprise,

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the ocean doesn’t have too many identifiable 
landmarks. Urashima freaks out and panics for

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a bit before remembering the box and thinking 
maybe there’ll be something inside he can use.

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Surprise surprise - there isn’t. When he cracks 
the box the only thing inside is a vaguely ominous

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cloud of vapor and the recollection that that 
was the one thing he was supposed to not do.

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Whoops! Whatever magic was in the box dissipates 
and Urashima gets hit with four hundred years of

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backlogged time all at once, rapidly aging 
all the way up into a corpse. Total bummer.

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Moral of the story? Well, aside from the 
standard “don’t disobey magical orders

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from fairy tale ladies”, maybe, you know, make 
sure you and your fiancee are fully on the same

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page before moving in together. You know, 
you might handle your chores differently,

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or have different standards of organization… 
that’s just the kind of stuff you should really

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talk out first. And also your fiancee’s house 
might be a relativistic anomaly that completely

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cuts you off from your friends and loved ones 
forever, which is just generally a red flag.

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[Maybe This Time]