> Paradox Gardens
>  by HorseStories
> --------------------------------------------------------------------------

> Prologue: Breakthrough
> --------------------------------------------------------------------------

Time Turner was a strange pony. In many ways, one of the strangest ponies in Canterlot. Which, of course, was saying a lot.

Earth ponies usually found jobs doing manual labour. Their raw strength and endurance meant they were perfectly suited to a life outdoors. Time Turner's own father had been a dock labourer in Manehatten, before a workplace injury had forced him into early retirement. Unable to do manual work, and with a wife and young stallion to support, he worked odd jobs all across Equestria until he finally found steady employment - working as a janitor at none other than the prestigious University of Canterlot.

Time Turner had spent most of his youth enthralled at tales told by his father of the wonderous magical going-on at the University. Stories of ponies who could levitate objects, disintegrate matter, and even control the moon and sun.

Even after learning that these feats were normally only possible for Unicorns, Time Turner remained determined to acquire this power for himself, pouring hours into studying what he considered to be the next best thing - science and technology. He soon discovered that, despite his initial reservations, he had a natural aptitude for the craft. As soon as he had completed his studies in Ponyville, and against the personal wishes of his parents, he travelled to Canterlot to petition for entry to the University.

As he had expected, the admissions officer had presumed the application to be a joke. Upon learning that Time Turner was, in fact, deadly serious, he had sneered and complained, but dutifully handed it in to the admissions office.

Time Turner would never forget the morning he had received his acceptance letter. He had been almost as astonished as his parents. He still kept a copy framed on the wall of his workshop:





Every time he felt down, or frustrated, it always cheered him up.

After graduation, he had sought a living as an inventor. For almost a year, he produced contraption after contraption, but to no avail. Ponies, he soon discovered, were far more interested in magical solutions than technological ones.

So, Time Turner had resolved to do something Unicorn magic could never have done. To prove that, once and for all, that science and mathematics had just as an important role to play in Equestria's future as magic - if not more so.

Magic, just like science, was governed by a wide array of laws and principles. For example, Thrust's Principle of Levitation held that the velocity of a levitated object could not exceed the terminal velocity of that object in air. Bolt's Principle of Directed Magic demonstrated that the energy of a beam of pure magical energy was purely a function of time and not, as previously thought, of the medium in which it travelled.

Science had always been held in some contempt by Equestrian society (hence the common nickname 'dirty magic') due to its association with Earth Ponies. But in recent years, more and more advancements in quality of life had come around as a result of scientific advancement. More and more ponies opted to be treated with medicine, as opposed to healing magic, and devices such as the Artificial Telekinesis Device (A.T.D.), a small headset which combined elements of magic and science to allow non-unicorns to levitate objects like unicorns.

Time Turner himself had played a role in the development of the A.T.D., and had been honoured by the Equestrian Academy of Sciences for his accomplishments. But his next creation would be sure to cement his place in history, and to truly open ponies' eyes to the potentials of science.

Almost a thousand years ago, Starswirl the Bearded had, after numerous failed attempts to produce a time-travel spell, concluded that pony magic could not affect the passage of time. In that thousand years since, ponies from all across Equestria had tried and failed to produce a working time travel spell, and had failed every time. Until now.

Time Turner felt his heart pound as his eyes swept over the gleaming chrome device. Shaking all over, he powered up his A.T.D., calibrated the main drive as precisely as he could, and flipped a switch.

A loud whirring noise filled the room, and the contraption began to shake violently. As Time Turner began to nervously back away, the machine slowly began to lift itself up in the air, and then, suddenly, it disappeared with a bang and a terrific flash of light.

As his vision slowly cleared, he scanned the room eagerly. Come on, come on...

The next minute seemed to take forever. Time Turner kept his eyes fixed on the digital clock he kept on the wall of his workshop. Five, four, three, two...

Another loud bang and accompanying flash of light signalled the return of his machine. Stunned, Time Turner fell backwards, bounding to his feet seconds later in joy. Galloping over to his machine, he broke into a mad dance.

His celebrations were interrupted by a banging on the door. Rushing to compose himself, Time Turner slid open the viewing hatch and peered through. 'Hello?'

'WHAT THE HELL IS GOING ON IN THERE!?'

Oh, her. 'Nothing! Just, uh, practicing a little science, heh heh. Very busy, sorrycantchatbye!'

Time Turner slammed the hatch shut, but the banging resumed almost immediately. The red unicorn soon added a chorus of verbal threats to her banging. Time Turner sighed, counted to ten, and then opened the door.

'Fire Ruby, how lovely to see you! I was just heading out, so if you'd just let me-'

'Oh, stuff it, moron. We both know you never leave your nest.'

Time Turner grit his teeth, but forced a smile back onto his face. 'Can I help you?'

'What in Tartarus is that thing?' Fire Ruby gestured to the smoking metal device sitting in the centre of his workshop. Time Turner glanced at the device, then at Fire Ruby, then back at the device, and once more at Fire Ruby.

'It's a time-space displacement engine. I have invented time travel.'

Fire Ruby's sceptical look quickly gave way to a poorly disguised grin, then a not-so-poorly disguised grin, and very quickly she was in a fit of uncontrollable giggles.

'You-you-bwa-ha-ha-ha! You...you... discovered... time... travel... oh, sweet Celestia, what a laugh!' Fire Ruby almost doubled over, tears in her eyes.

Time Turner felt the biggest, smuggest grin he'd ever had cross his face. 'I'd be more than happy to demonstrate.'

Still giggling slightly, Fire Ruby looked up. Seeing Time Turner's confidence, her mirth slipped slightly, but she showed no signs of giving in. She nodded, an uneasy grin on her face. 'All right. Show me.'





Upon witnessing the time machine, Fire Ruby had gone into shock for a few minutes. After much protesting, and several demands involving clocks and temper tantrums, she had finally collapsed in shock into a nearby chair.

As fun as it had been to get one over her, Time Turner felt a little bad for gloating so much. Fire Ruby was an old friend, a roommate of his, and a rising star in the magical world. The two of them had met at University, where she had been studying Theory of Magic. Although she had never passed up a chance to mock his interests, she had nevertheless become a good friend of his. Usually bold, bratty and competitive, she now looked utterly shaken.

Time Turner glanced down in concern, waving a hoof in front of her face. 'You okay there, Rube?'

That worked. Fire Ruby snapped out of her fugue to smack his hoof away. 'Stop calling me Rube!'

Time Turner chucked. 'Make me, shorty.'

Fire Ruby's horn ignited, and Time Turner found himself picked up and slammed into the closest wall. Scrabbling to his feet, he quailed in under the smouldering gaze of Fire Ruby.

Fire Ruby took a step forwards, then grinned. 'Coward'.

Turning her back, she took another look at his time machine. 'So... you really did it. And here I was thinking you'd never top that floating thing. I wonder if-'

Her monologue was cut short by the door to the workshed busting open. A grey blur blasted into the workshop and collided with Fire Ruby at such speed that the she was sent sprawling. The grey blur immediately rose in the air and began to frantically scan the room.

'Doc? Doc?'

Time Turner sighed. 'Over here, Derpy. And my name's not doc, it's Time Turner.'

Derpy fluttered to his side, a letter clutched in her mouth. Time Turner plucked the letter from her mouth with his A.T.D., and she gave a sheepish grin. 'I know, but "Turner" sounds kinda strange. Hey, can I call you Timey for short?'

As Fire Ruby struggled to her hooves in the background, Time Turner shook his head. 'Not in a million years. How was the round?'

Derpy shrugged. 'Not so bad. A few ponies wanted to know if you'd made any new stuff, but I told them no. Unless you've whipped up the cure to cancer while I was gone!'

'Well, you could say that...' Time Turner murmured, glancing behind him. 'Oh, here she comes.'

Fire Ruby, face red with anger, stormed over to Derpy and made a valiant attempt to get in her face. Straining on the tips of her hooves, she was just able to make her eyes level to Derpy's snout.

'What's wrong with you? Can't you see where you're going, you useless sack of-'

Derpy cut across her, smiling innocently. 'I'm sorry, Fire Ruby! I just didn't see you when I came in. It'll never happen again, I promise!'

Sensing a fight, Time Turner cut in between them and spoke up. 'Fire Ruby, I'm just going to show Derpy my latest invention.'

Fire Ruby sniffed, and curtly turned her back before storming off. Time Turner turned and smiled apologetically at Derpy. 'Sorry, she's a little sore.'

Derpy grinned. 'She gets wound up to easy.'

Time Turner scowled. 'You could at least try to be considerate.'

'Stuff it, doc. What did you have to show me?'





Derpy's reaction to the time machine was to immediately list of various places she wanted to go, and what she wanted to do there. In the middle of her rant, Fire Ruby tapped Time Turner on the back and gestured for a moment alone. Confident Derpy would not miss his presence, he followed, and let himself be led away.

The moment they were alone, Fire Ruby confronted him. 'Spit it out. How did you do it?'

Time Turner swelled with nerdy pride and smugness. 'Aren't you going to ask nicely?'

Realizing he was serious, Fire Ruby cringed and managed to wrangle the words out. 'Please tell me how it works.'

Time Turner grabbed a nearby notepad, and, levitating a pencil in his A.T.D., began to scribble.





Fire Ruby stared blankly at the sheet. 'And this means?'

Time Turner tapped the diagram at the top of the page. 'See this? It shows how timelines diverge. There are two types of divergence - temporary ones, that resolve themselves by more or less reconverging with the original timeline. That's what A' is. And there are permanent divergences, like B, that change the path of reality forever and destroy the original timeline.'

Time Turner continued. 'Broadly speaking, if a chrononaut - a time traveller - doesn't make too much of an impact, the timelines will reconverge, though normally not perfectly.'

Now, Time Turner tapped the equations at the bottom of the page. 'Now, we've known about timeline branches for a while, but this is my own work. I discovered that the time displacement either way in nanoseconds - τ - is equal to the product of the rest mass of an object and the time displacement constant of a device, γ, measured in ns m-1. It's around 0.2, but I haven't narrowed it down much yet.'

'Now, given the already established relationship between mass, energy and acceleration -' Time Turner tapped the top rightmost equation '- and knowing that the device has to be capable of transporting through space as well as time, we can find the product of the two to calculate the work required to transport an object through space and time.'

Fire Ruby tapped the final equation. 'So what’s the acceleration here represent?'

'Ah. Well, that's the sum of all accelerations on the object. Normally that would be the acceleration of gravity - 9.81 m s-2. Which means moving around a month in time would take about 400 TWh. But I, uh, I found a way around that. See, if you can temporarily increase the gravitational attraction by a large amount, the energy required drops dramatically. In addition, the work done is surprisingly not proportional to the mass of the object transported, as long as the object moves in space at the same time. So what I needed was a small, ultradense, temporary mass that would disappear after a short while. Which turned out to be a small, highly localized... black hole.'

Seeing Fire Ruby's jaw drop, Time Turner quickly continued. 'The lifespan of a black hole is inversely proportional to the square of its size. So it's perfectly safe to create micro black holes for this purpose.'

Fire Ruby shook her head. 'Unbelievable. And you're sure it's safe?'

Time Turner nodded. 'Perfectly safe'.

'Well, all right, if you say so. You're the scientist, after all.' Fire Ruby looked Time Turner up and down, and gave a small smile. 'Who would have guessed a country bumpkin like you would do something like this?'

Time Turner smiled back. 'So, were do you want to go first?'

'Uh, excuse me?' Fire Ruby looked at him oddly. 'You've got a Neighbel prize waiting for you.'

'Somehow I don't think I'll miss it.' Time Turner grinned. 'Come on. You must have somewhere you've always wanted to go. My treat.'

Fire Ruby still looked unsure, but Time Turner could see she was tempted. 'Well... just one trip, right?'

Time Turner leant down and she moved forwards to whisper in his ear.

Before he could stop himself, he burst into laughter. 'Really?'

'Shut up!'

Time Turner stopped and nodded. 'All right, sure. Derpy should come too, she'd like it.'

'Ehhhh...' Fire Ruby looked unsure. 'If you want.'

Time Turner scrunched the notes he had written into a ball and tossed it aside. 'Come on. We've only got all the time we want.'