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

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

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and find only seconds have passed since you left [br]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 [br]the whole time you’re gallivanting around in

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

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

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

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

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

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

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

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

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

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

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

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This is bananas, you may [br]remember it from Interstellar,

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

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

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by the very nature of space-time……… or maybe [br]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 [br]japanese folktale about the dangers of magical

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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because she has a feeling something very bad might [br]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 [br]circumstances or he won’t be able to come back.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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[Maybe This Time]