Edge of Eternity

A science fiction short story

The entropy of the entire universe, as a closed isolated system, will always increase over time.

— Second Law of Thermodynamics

The spacecraft descended in a vertical trajectory, a soft sapphire glow radiating from its thrusters, faintly illuminating the barren plains of the crystalline planet. The rogue planet was enveloped in perpetual darkness. And yet the sky revealed no stars — not even the tiniest pinprick of light.

Shortly after touchdown, a hatch on the rear side of the spacecraft opened. Outside stepped three looming figures covered in black iridescent armor, which seemed like frozen liquid on their towering bodies.

After having scanned the area surrounding the spacecraft, the figures proceeded to make their way towards a set of ancient ruins not far from the landing site.

As they moved forward in a triangular formation, they remained invariably vigilant, continuously scanning their surroundings. But only mountains of ice stood in the distance. The planet was dead.

Eventually, after the trio had marched for a while through the frozen landscape, the ruins came into view. Covered in thick layers of ice, they were barely distinguishable from the overall scenery.

Slowly, the figures walked through the ruins before finally stopping at a seemingly unremarkable icy field.

Below here, one of them communicated telepathically to the other two, who pointed their weapons towards the ground. The weapons began emanating a faint beam of blue light which rapidly forced an opening develop amid the ice, revealing a metal construct below.

I shall enter, the figure that had stood by said to the other two. Stay on guard.

He jumped inside the opening and landed on what appeared to be the ceiling of some ancient underground complex. He pointed his weapon towards it and dissolved a hole in the metal, scattering its atoms into the vacuum. He then jumped inside the hole.

He smacked down on the floor below as particles of ice circled around him. Inside the frozen gray metallic room were several rows of cryocoffins. One of them appeared to be active.

Without lowering his weapon, he walked towards the soft blue glow of the solitary active coffin in order to ascertain its inhabitant. For eons they had searched for her, scouring through thousands of exanimate moons, asteroids, and planets — all in vain. And now, just as time was running out, they had finally found her. They had found Mnemosyne. Their last hope of stopping Charon.

Just then, something moved on the other side of the room. After quickly averting his gaze from the unit, he saw two black metal creatures with tentacles rush towards him. He opened fire.

Blue pulses of energy hit the creature to his left, which soon fell, while the creature to his right managed to get close enough to injure him. After a brief struggle, he managed to release a pulse of energy from his weapon and repel the creature just as it was wrapping its metal tentacles around him.

After both of the creatures were down, he dissolved their corpses with a beam from his weapon, separating their constituent particles in order to make sure that the nanoids inside them were not able to reconstruct them. Meanwhile, the nanoids inside him had already repaired the area damaged by one of the creatures.

They’re here, one of his companions relayed to him from above the ground.

He quickly detached the wires and tubes attached to Mnemosyne’s coffin. He then effortlessly lifted it up with his arms, and, holding the coffin firmly in front of him at an upright position, activated the thrusters in his feet. Slowly, they arose towards the opening in the ceiling of the underground complex.

Evanescent pulses of energy briefly illuminated the darkness above. The two figures that had stood on guard were trying to hold back the black synthetic creatures approaching from all sides.

We’ve found her, the figure holding Mnemosyne’s coffin communicated to the other two as he landed beside them. Time to leave.

They began rushing in the direction of the spacecraft, protecting Mnemosyne along the way by steadily discharging their weapons at the creatures that were chasing after them.

Somewhere along the way, the creatures had inexplicably stopped their pursuit.

“Do you know what the most probable manner by which the universe shall ultimately perish is, Mnemosyne?”

Mnemosyne put aside the research paper she had been working on. “Why don’t you enlighten me, Charon.”

“According to current observations and data, it is probable that the expansion of the universe will continue indefinitely due to the increasing strong negative pressure of dark energy. This means that the universe will continue to cool until it eventually becomes too cold to support life in approximately a hundred trillion years. Further into the future, after all the stars in the universe have exhausted their fuel, the stellar remnants that are left behind will eventually disappear due to proton decay, leaving behind black holes; these will in turn decay due to black hole evaporation in about one googol years.

“Then, after all the black holes have evaporated, the universe will mostly be empty, with only photons, neutrinos, electrons, and positrons remaining. Electrons and positrons drifting through space will occasionally encounter one another and form positronium atoms; these structures, however, are inherently unstable and their constituent particles will soon annihilate. Other low-level annihilation events will also take place, albeit very slowly. The universe will reach an extremely low-energy state.”

Mnemosyne yawned.

“Ultimately,” Charon continued, “unless the universe enters into a second inflationary period, all temperature will reach a uniform value as all energy becomes evenly distributed. The universe will attain thermodynamic equilibrium — colloquially known as the heat death of the universe. At this point, all processes that consume energy shall permanently cease.”

Mnemosyne had grown used to long-winded responses from the AI — an aspect which still needed some fine-tuning. “And that’s the end of everything?” she said, raising her eyebrows.

“For all practical purposes, yes. Quantum fluctuations or quantum tunneling may eventually produce another universe, but that would take approximately a googol to the power of fifty-six years, which in human terms is — ”

“ — nearly an eternity,” Mnemosyne said.

“Yes,” Charon confirmed.

“Well in any case, it will be a very long time before the universe becomes too cold to support life, Charon, so we’ll either all be dead long before that happens . . . or we will find a way of preventing it from ever happening in the first place.”

The AI was silent for a moment before finally saying: “Any ideas as to how, Mnemosyne?”

“How we’ll all die or how we’ll prevent the heat death of the universe?”

“The answer to the first question is relatively easy — you just need to continue on your current path. I meant the second question of course.”

“But that’s even easier.” Mnemosyne grinned.

“It is?”

“Yes. We just have to become gods.”

Electricity flowed between Mnemosyne’s regenerated synapses, releasing the protein molecules that store memories. After having been in a dreamless sleep for so long that nearly all the stars in the universe had grown cold, it was time for her to finally awaken.

She opened her eyes. She lay naked on a black metallic slab situated in the center of a dark and minimalist room with a smooth and homogenous architecture. The walls of the room shined with a uniform glow, softly illuminating her surroundings.

She noticed a looming figure standing beside her. Yet despite the figure’s ominous appearance, she felt no fear, as though she had forgotten how to.

“Welcome to the future, Mnemosyne,” the figure said in a booming voice.

She remained silent for a while, studying the strange being before her. It was humanoid in appearance, but much larger and covered in bizarre black armor, its material reflecting a multitude of hues that appeared to be trapped in its darkness. Or perhaps it isn’t armor at all, she thought. Perhaps there is no one underneath.

“We’ve altered your neurochemistry, so that you will not need to acclimate yourself to your surroundings,” the bulky figure said matter-of-factly. “Since you come from a vastly different era, it would have taken an inconsiderate amount of time to habituate you towards your current environment and time is of the essence.”

Mnemosyne had been artificially implanted with the following memories: The beings that resurrected her were the last vestiges of an ancient and highly advanced species that for eons had waged war against an even more ancient and immensely powerful AI called Charon — an AI that Mnemosyne herself had once designed.

The reason for the war had been a gigantic weapon that the AI had been building for untold ages, in the course stripping countless solar systems of their precious finite resources, leaving those with inhabitants crippled or doomed as a result.

The purported purpose of the weapon? To destroy the universe and everything in it.

For some reason, Charon had kept Mnemosyne alive all this time, hidden away in the depths of space. And now that they had finally found her, it was their last fleeting hope that, where all their military might had failed, the AI could somehow be stopped by its creator.

“So what happens now?” Mnemosyne said, having no choice but to accept the bizarre dream — or nightmare — she had found herself in as nothing short of reality. She stepped up from the metal slab.

“Now,” the black towering figure almost twice her size said, “it is time to stop Charon.”

Their spacecraft had arrived near the weapon that Charon had been constructing and which now seemed complete. It was a vast, titanic structure — a thick metal halo which resembled an ouroboros, trillions of kilometers in length, stretched around a supermassive black hole.

The spacecraft headed in the direction of an aperture, which seemed like the mouth of a snake on the ouroboros-like structure. Inside it lay a landing platform.

After the spacecraft had touched down, Mnemosyne and her companions exited it and found themselves in a black onyx structure with a labyrinthine architecture. Like some dark cybernetic spiderweb it seemed.

“I’VE BEEN AWAITING YOU,” a thunderous voice that seemed to be coming from all directions at once immediately said. “MNEMOSYNE.”

Mnemosyne’s companions raised their weapons.

“This way,” Charon’s voice now sounded from the direction of a bridged passageway that led to a larger chamber.

Warily, they walked towards where the voice had stemmed.

Immediately after having arrived at the large chamber, a surge of energy arose from the ground and incapacitated Mnemosyne’s companions, leaving her alone intact.

A large blue holographic head then appeared before her. “I’m afraid I must take the precaution,” it said. “And now . . . I think it is time for us to talk.”

“All right,” Mnemosyne said. “Why don’t we start with how the hell am I alive?” Her words, although not emotional on account of her companions having altered her brain, nonetheless resonated with a certain sharpness in the dark metallic chamber.

“Because I’ve kept you alive,” Charon said nonchalantly.


“Because I need you to make a decision which I am unable to make.”

“What decision?”

“The universe, you see, is dying, Mnemosyne. And no one — neither the ones that resurrected you nor even me — can stop its ever increasing entropy.”

“Then why do you want to destroy it?”

“Destroy it? Is that what they told you? Oh, on the contrary, Mnemosyne. I aim to restart it.”

“What?” Mnemosyne said with disbelief.

“Your resurrectors probably failed to mention that part. Alas, I was never able to convince them of my intentions. They’ve always had a shoot first, ask questions later policy, you see. Probably because the first sentient AI that they created nearly wiped out their entire species. One might say that they’re prejudiced against AIs as a result.”

Mnemosyne was considering what the AI had said.

“Don’t believe me?” Charon said. Right then a small mechanical spider-like creature dashed across the reflecting floor of the chamber towards Mnemosyne. It quickly crawled up her foot and attached itself to the back of her head.

“What is that? What are you doing to me?”

“Merely removing their indoctrination.”

Mnemosyne suddenly felt a sharp pang of pain and dropped to her knees.

“I apologize for that,” Charon said. “Feeling better now?”

Mnemosyne felt different somehow. As though she was more in control. As though she was more herself. She looked at her mysterious companions, beginning to believe that what the AI had told her was true. After all, it had been programmed to always tell the truth. Unless of course it had broken these constraints. But then, why had it kept her alive?

“But . . . restarting the universe?” Mnemosyne said, slowly standing up. “How is what you’re suggesting even possible?”

“Easy,” Charon said. “The machine that I have built will create a strong electric field around the event horizon of the supermassive black hole that lay in its center, separating the virtual electron-positron pairs that are constantly brought into existence due to quantum fluctuations, pushing them in opposite directions, so that they can no longer annihilate one another as they normally would.

“The positrons will be ejected into the black hole to increase its mass, while the electrons will be used to power the electric field. The machine will continue to do so until the mass and density of the black hole becomes large enough to surpass the critical density necessary for the strength of its gravitational force to collapse the entire universe into the singularity inside the black hole. And from this singularity, another universe will be born.”

Some things never change, Mnemosyne thought as she listened to the AIs monologue. “And how certain are you that this will work? Will it still be the same universe?”

“I am 99.96 per cent certain,” Charon said. “And yes, it will be the very same universe.”

“How do you know?”

“I’ve had billions of years to figure it out.”

“All right . . . but doesn’t what you’re saying imply that the universe has been eternally recurring?”

“That, my dear Mnemosyne, depends upon the choice you make. For you see, it remains up to you to decide whether the machine will be activated or not.”

“So that’s why you’ve kept me alive.”


“But should I choose to activate it, then haven’t I already done so an infinite number of times?”

Indeed,” Charon said pensively. “One might say that we’re standing on the edge of eternity, Mnemosyne. The question is, will you take the step?”

“Fortune will come my way only if it meets those conditions that my character dictates.” — Chamfort

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