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Luna answers. Page 2/2. Enjoy.
And I really doubt Luna would be pleased with seeing what the Dreamlands-Moon is like. Moon-beasts and Nyarlathotep worshipers everywhere!
Does this earn me some sort of science badge from The Smiling Pony? XD
How so, you may ask? Special relativity!
Let’s say Twilight Sparkle builds a super-rocket that can go up to 259,620 kilometers per second - that’s 86.6% the speed of light [1]. If she were to launch from Equus, then once she’s reached that speed relative to Equus, some interesting things would happen:
like the creeps they arethey see her moving in slow motion, as well. I picked 86.6% the speed of light, because at that speed, they both see eachother moving at half speed.So, let’s say 1 year into the mission, Luna decides to visit Twilight’s dreams. So she checks on Twilight through the telescope - sure enough, only six months have passed on Twilight’s calendar, [2] because of time dilation - and nods off to slumberland, to reach Twilight in the blink of an eye.
She arrives, chats, and spends an amount of time that’s negligibly small compared to the six months that have passed for Twilight, before having to head back to Canterlot for her duties. Only one problem - she decides to once again, use her blink-of-eye speed to zip back to Canterlot. The issue with that is, Twilight also sees Canterlot move at half-speed-slow-motion, so from here, looking back, only 3 months have passed for Canterlot. Sure enough, should Luna instantly teleport back to Canterlot, she would arrive 9 months before she left.
But, what if she’s tethered to her body in a way that makes it so she’ll just return back to when she left? Well, then we can still do something fun. Let’s say Twilight wants to show off a cool dream-machine she made: it makes you dream of what your senses see, and then you sleepwalk - in other words, you’re awake, but still technically dreaming, so dreamwalker Luna can stick around in the waking world with Twilight!
Dreamwalker Luna decides to hang out with Twilight for the rest of the trip. Twi turns the spaceship around and comes back to Equus. It takes another six months for Twi to get back, so in total she’s aged a year. However, something odd has happened…
The Canterlot observatory has been watching Twilight for the whole flight. Now, Special Relativity applies directly for frames of reference that are inertial, that is, they don’t accelerate - they just go at a constant speed, and gravity is ignored. But when Twilight turned the spaceship around, she slowed down to 0, then sped back up to the opposite direction, so instead of applying special relativity to her point of view, which experienced acceleration, we use it to ask; what does Canterlot see? Well, because of how relativity works, Canterlot sees her move at her half-speed the whole time, all the way up until she stops back at Equus. As a result, although only 1 year has passed for Twilight, 2 years have passed for Canterlot.
This does interesting things for dreamwalker Luna… Remember, Luna left when her calender in Canterlot said “Twilight left 12 months ago,” and showed up in Twilight’s spaceship when Twilight’s calender read; “left Equus 6 months ago.” So Luna’s been hanging out with Twi for 6 months. However, instead of being 12+6 = 18 months since Twi left - the amount of time that’s passed for Luna since Twi left - , Luna’s now in Canterlot 24 months after Twi left! This means Luna is in the future by 24-18 = 6 months.
So as soon as she stops dreamwalking with Twilight, she’s going to travel 6 months into the past.
The best part is, she’s going to dreamwalk around Canterlot with the returned Twi, meet herself, then later wake up, wait 24-12 = 12 months, then Twilight will return, and meet her dreamwalking self from the past. If time is a self-contained deal, then she’ll experience the same encounter twice, once from her past self’s perspective, the other from her current self’s perspective Xp This also allows for her to make fun paradoxes: like for example, say she meets her future-self, and future self warns her: “Don’t let Celestia paint my room with yellow polka dots. Somehow she convinced me to let her do it. I regret it. Also, here’s a theory about gravity… [explains theory]” So sure enough, once she wakes up, and Celestia approaches her with the idea, she turns it down. Then she goes on to write down the theory she learned from her future-self. Then a few months later, her past-self arrives with Twilight. But, having already turned down the polka dots, she doesn’t feel the need to warn past self anymore. So where did she get the idea from?… But, she does decide to tell her past self about the theory that future self told her. So, where did the theory come from, then?
If it were a trinket, or a pet possum or something instead of just a theory, then how old would it be?
[1] For comparison, the fastest humankind has ever been capable of sending someone one-way, is with the Saturn V rocket, 3,000 tons and 30 stories tall, could put you somewhere at 16 km/s, less than 1/10,000 of Twilight’s in this thought experiment (still a fantastic achievement, though - 16 km/s is 390x the energy per gram as a rifle bullet). I picked such a fantastic speed so that the math would be easy, though. In principle, if you go a lot father out, take a longer trip, then you can get the same effect for a lesser speed. Or conversely, you could use a Saturn V, have the trip be the same length, but settle for only a few seconds of time travel or some other extremely small length of time.
[2] More precisely, you’d see old light-signals from Twilight from months before that, but calculating how old the light-signals are because of how long they’ve taken to reach you, you’d calculate that it’s currently been six months for her.
@McClaw
@JP
>>799176p
That would imply she’s a “bad dream”.
Although I could see something like a dreamcatcher being hung above sleepers who want or need Luna’s attention, sort of like setting a beacon for her. “Here! Over here!”
I can never sleep again.
My sides!
(For those who don’t want to go look it up, dreamcatchers are designed like small nets and hung above the sleeper. Good dreams are supposed to be caught and drip down to the dreamer; bad dreams stay in the ’catcher and dissolve in the morning.)