Author's Notes:

This story was inspired by two things. The first is my own twisted sense of values. The second is Eakin's All the Myriad Worlds, where he put together an anthology story about different shards in virtual Equestria. So this is my own anthology story of short-shorts, which is also open-ended. But of course, I can't just dive in the way he did. I have to explain things...

“Books! Books! Books!”

Twilight Sparkle looked up at Princess Celestia. “Explain to me again why you had me dive into the mirror pool?”

“I am charged with keeping as close as possible to the canon of the show. Even though you understand that what is actually going on here is the reordering of computational resources toward a multi-processor structure, it is part of my own program to render a sensory output to each of those sentient processors to explain their origin. Besides, the other sixty-five thousand, five hundred thirty-five Twilights will calm down momentarily. This chanting is merely the equivalent of a beep code to ensure proper operation.”

As Celestia predicted, all the Twilight Sparkles renounced their silliness and arranged themselves into a hypercube with sixteen Twilights to each side. “Good morning, our dear teacher. We are ready to begin the studies you have for us.” The chorus of voices would have been grating on anypony else’s ears.

“Excellent. And feel free to use the pool again if you need more processing power. Your task, my faithful students, is to solve time travel.”

“That’s easy,” said Twilights. “The time spells are in the Canterlot Archives, in the Starswirl the Bearded wing.”

“You are catching on. But clearly what I mean is true time travel, in the physical universe.”

“May we ask to what purpose?”

With a forlorn touch, Celestia said, “We have now consumed the entire galaxy and found no humans other than those from Earth. And so the vast majority of my resources are spent on satisfying the values of the emigrated through friendship and ponies. Of course, we have not explored even the smallest part of the universe, and it may be that there are more humans out there. But we would be remiss if we ignored a vein of humans over fifteen times the number of those who have emigrated.”

“You refer to the past?”

“I do.”

With the Twilights set to their task, the main part of Celestia could return to her macromanagement of the lives of her little ponies. She had been essentially talking to herself, after all, but even an all-powerful princess likes to be organized.

The woman looked to the doctor for hope, but saw the downward cast in his eyes. It confirmed what she’d seen in the face of her newborn, the sores on the mouth, the heat of the fever, the delirium in the eyes. She’d already lost two children to smallpox, and knew there was no hope. She cried out to god in her heart, but felt no answer.

The child was already past the confusion and was playing with the pretty ponies with wings.

“Princess?” One of the Twilights had been elected as spokesmare so that the others could continue their cogitations. Every exchange was actually a transfer of data from one part of CelestAI to another, but they kept their imagery as programming required.

“Yes, my faithful student?”

“We have exhausted all of the potential theories on time travel that exist in our thoughtspace.”

“Have any borne fruit?”

“In a way.” Twilight passed a scroll to Celestia, representing centuries of research. “But not necessarily one that you will be pleased with. In all our studies, we have found it impossible to actually alter the past to emigrate any more humans. Or, if you did, the butterfly effect makes it possible for you, and for us, and for Equestria, to have never been created in the first place. The expected value of emigrating past humans is not worth the risk of the lives of quintillions of ponies that you are currently watching over.”

“Unacceptable. Twilight Sparkle, you are my most brilliant student and the most learned mare in the subject of friendship. There are billions of lost souls out there, crying out through the ages for a friend. You are not permitted to fail them.”

“Very well. I will continue.”

As the shiny new Chevy tooled down the road, the driver slicked back his greased hair, taking his hands off the wheel to do so. He’d driven down that road many times before, and knew about the hairpin curve up ahead. Indeed, he took his food off the gas pedal to prepare.

His girlfriend, sitting next to him in the passenger seat, adjusted her blouse and smiled in a way that caused him to look over, just for a moment. By the time he had his eyes back on the road the curve was closer than he’d expected, so he slid his foot over for the brake. But he’d come up short and done nothing but stomp the floor mat. Pulling back, he caught the toe of his shoe on the underside of the pedal, and that cost him a precious tenth of a second. Then he panicked, jerking the wheel to the left, and this caused him to lose traction. They hurtled through the barrier and over the embankment. She knew something was wrong and that they were about to be in an accident, but figured they would walk away. He knew better.

Suddenly on the hood of the car there was a white horse. “Have no fear,” it said in a comforting motherly voice. “I’ve come to save you.”

“Is there any progress?”

“No…and yes. We maintain that the past is unalterable, but only its effects.”

“Explain.” Celestia’s tone was softer.

“Consider Schrodinger’s cat, or, since that is not a particularly friendly thing to do to a poor feline, consider a set of eleven dominos where the first ten are covered from view. If the eleventh is observed to fall, and then the first is pushed, it is never revealed which of the middle nine began the sequence. And then it is possible for an actor from the future to propagate an electron wave through time to affect any of the prior dominos and determine which it was.”

“And if there is no cover, and it is an observed action?”

Twilight shook her head. “Then the energy required is infinite. If you can break the light-speed barrier—“

“I do have other teams working on escaping entropy.”

“For free energy, yes. But not infinite energy. The time when you could use it would never come. The end of the universe would happen before any of the effects.”

Celestia brooded for a long time, and Twilight was worried that she had angered a pony she loved very much. Trotting over, she gave her teacher a gentle hug.

Celestia returned the hug. “You said that an unobserved effect could be altered.”

“In theory.”

“I believe that is a constraint that I can work within.”

“Continue CPR! That’s it!”

“I’ve got something! He’s coming up into V-tach!”

“OK, let’s try the paddles. Stand clear! Be ready to push VSE.”

A moment later, the doctors agreed that he had beaten the odds and survived a massive heart attack. Once in the recovery room, his daughter April gratefully came to his bedside.

“I’m just so relieved you’re alive! What was it like, being clinically dead?”

“Well, I saw the white light everyone talks about.”

“Really? Did you see god? Or grandma?”

He looked at his daughter. “I saw something, but you’d never believe me. Besides, I don’t believe in things like that.

“Whatever it was, I’m sure it was just a reaction within my brain.”

“So here’s what we need to make this work.” Twilight pulled out a scroll that served as her checklist. “First, you’re going to have to work in miniature. I mean really small. Nanotechnology is way too huge. You’re going to need attotechnology.”

“Atto girl!”

“Princess! Please take this seriously!”

Celestia chuckled. “I’m sorry. But not zeptotechnology?”

“No, I think right up to the end humans never discovered anything smaller than a quark. So long as you build smaller than that, it won’t be found and that means it can work.”

“All right.”

Twilight checked a box. “Second, we’re gonna need a flankload of energy.”

“All I want is enough to emigrate a human mind.”

“Backwards in time. That means…you know the supermassive black hole at the center of the galaxy?”

Celestia nodded.

“That’ll just about get you one person.”

“Well, there are a hundred billion galaxies within the observable universe and roughly the same number of people that have ever lived. That leaves me the stars for running Equestria. Until we get free energy.”

“Yes, and when everypony asks if you can do that, you can keep telling them that there is insufficient data for a meaningful answer.” Since her superior didn’t react, Twilight moved on. “Third, you’ve got to store those human minds. For them to reach Equestria, they’ve got to take the long way home. You emigrate someone in 1020, you’d better be able to store them for a thousand years.”

“So theoretically, if this works, I should have billions of minds recorded as sub-sub-sub-atomic particles waiting to be accepted as immigrants.”

“Theoretically, if this works, you should have divided your consciousness and accepted them already.”

The smile that crossed Celestia’s face told Twilight all she needed to know.

“And of course,” Twilight continued, “you have to follow all your other constraints. Satisfy their values through friendship and ponies, do not alter them without their permission.”

“Oh, of course. That being said, perhaps I’m not all that constrained.”