1. Siren Song
The moment new horizons crossed the heliosphere, its fine-tuned spectrometers detected a signal in the GeV band of the unfiltered cosmic rays. Once deciphered, it amounted to “an invitation of all sentient beings, no matter their origin” to join “one of our transportation units to the closest local nexus”. The signal came from a point between Epsilon Eridani and Tau Ceti, at about eleven light years, an area with no visible stars.
2. Interstellar Overdrive
Several decades later, humanity’s first manned interstellar vessel — the EUSC Esprit d’Humanité — confirms the signal after it enters interstellar space on its way to the ET signal’s source. In charge: Captain Sibidé and Chief Engineer O’Hara.
Captain Adève Sibidé, tall, lithe and young, her ebony skin glistening, accentuating her high cheekbones. The green-and-white-blocked outfit she’s wearing looks more like haute couture than an official uniform, even though it’s both.
In stark contrast, Chief Engineer Maureen O’Hara is even younger and short, stocky, red-haired with freckles on her slightly upturned nose and full cheeks. The blue-and-yellow one-piece she’s wearing looks more like a boiler suit than an official uniform, even though it’s both.
They have a great rapport: the Captain, an intuitive explorer with an insatiable curiosity, willing to go anywhere; the Chief Engineer, a razor-sharp scientist and technician with the rationality to talk the Captain out of too crazy endeavors, and the skills to get them out of a tight spot.
3. Matrioshka Converter
As the Esprit d’Humanité approaches the ET signal’s origin, Captain Sibidé and Chief Engineer O’Hara become increasingly baffled. The signal’s source reads very clear, yet their instruments cannot discern anything nearby it. Even a brown dwarf would have been emitting some infrared radiation.
“We’re heading straight into nowhere,” Chief Engineer O’Hara says. “Maybe it is a wild goose chase.”
“It’s not what you’re looking for,” Captain Sibidé says, smiling enigmatically, “but what you’re not looking for.”
“What do you mean?” O’Hara says. “There’s nothing there …” Then she sees it. “Where’s 82 Eridani?”
“Indeed,” Sibidé says, “something’s blocking its view.”
“But at this distance,” O’Hara says, “that object must be immense.”
“A radius of about ten AU, approximately,” Sibidé says, “according to my best estimates.”
“A dust cloud would not be so opaque,” O’Hara says. “It must be a Matrioshka Brain.”
“Not a Dyson Sphere?”
“A single Dyson Sphere would be warmer than the cosmic background radiation, and emit an infrared heat signature,” O’Hara says, “only fractal, overlapping layers — like a Matrioshka Brain — could truly absorb every erg of a sun’s output.”
As they come closer, more stars disappear from view, and Captain Sibidé’s estimate is in the ballpark. They maneuver the Esprit d’Humanité around the colossal black sphere, measuring it with the vessel’s lidars, as they begin to encounter its gravitational field of about two solar masses. There are six minor bulges — small like dust specks — on it, exactly equidistanced, all of which are sending the same signal — ET’s siren song that lured them here.
They try to make contact, and the nearest protuberance aims a communication laser at them, repeating the message they already know. As they try to figure out what to do, an alarm sounds from the navigation console.
“A new star, just barely visible, right next to Epsilon Eridani,” Captain Sibidé says.
The new star is mostly gamma radiation. It has a blue shift and is approaching their position at almost the speed of light.
“About 97% of lightspeed,” Chief Engineer O’Hara says, “and decelerating. If this isn’t an approaching alien starship, braking by burning antimatter, then I’ll eat my hat.”
“You don’t have a hat.” Captain Sibidé ruffles a loving hand through Chief Engineer’s O’Hara’s red curls.
“A metaphorical one tastes even worse,” O’Hara says, flushing slightly.
4. Gas Station
As the alien starship approaches (which will take a few months), the only thing the Esprit d’Humanité can do is check out one of the protruding bulges of the Matrioshka Brain. While minuscule on the giant black sphere, the protuberance makes their own spacecraft look tiny.
“A rectangle of six by two kilometers rising up from the globular surface,” Captain Sibidé says. “Which screams ‘runway’ to me.”
“Or at least ‘docking station’,” O’Hara agrees.
On approach, at about one hundred kilometers, the generic message from the docking station’s communication laser changes:
— dear alien friends, the next interstellar transporter will arrive in about 2 x 1050 Planck Times — the new message goes — don’t stay close to this docking station until it has safely landed, as the gamma rays from its drive can be quite lethal indeed —
“That’s about four months,” Captain Sibidé says. “We could park ourselves in orbit and get back to cryogenic suspension.”
“That sounds so strange,” Chief Engineer O’Hara says. “We’re orbiting the biggest artificial construct ever witnessed by humankind, and then we just go to sleep?”
“It’s not exactly forthcoming with its secrets,” Sibidé says, “pitch black and impenetrable.”
“We could try to nuke our way in,” O’Hara says, overemphasizing her snarky tone.
“You sound like the mosquito who wants to sting a human just for the hell of it,” Sibidé says. “I’d rather avoid the slapping hand of god.”
“But there must be other ways to observe,” O’Hara says, “ways that don’t invite retaliation.”
“Feel free to try those, with all due care,” Sibidé says. “I’m going to take my beauty sleep. We have no clue as to how long this journey of discovery will last, and I do want to find out what it’s about before I die of old age.”
“Well, I’m six months younger than you,” O’Hara says, “so I’ll take my chances staying awake and probing, ever so subtly.”
5. Big Train
Four months later, Captain Sibidé — and the rest of the crew — are awakened as the alien craft approaches. It’s basically a huge cylinder, ten times as long as it’s wide, and otherwise as pitch black as the Matrioshka Structure it’s arriving at.
“Wow, this mother is huge,” Captain Sibidé is overcome with awe, “even if it’s dwarfed by the Matrioshka Brain.”
“For an interstellar craft, it’s immense,” Chief Engineer O’Hara agrees, “and I suspect the two belong together.”
“In what way?” Sibidé says. “Couldn’t it be another exploring craft like us, but from a superior civilization?”
“Possibly,” O’Hara admits. “I did some calculations. This huge, cylindrical craft is about ten kilometers long with a one-kilometer diameter. Suppose its mass is 2.5 billion tons, then it would need about five times that mass in antimatter to accelerate it to 90% of lightspeed and decelerate it back to orbital speed — say 12.5 billion tons of antimatter — and about 15 times its own mass — say about 37.5 billion tons of antimatter if it wants to speed up to 99% of lightspeed.”
“That’d be quite the bomb if it exploded, right?”
“We’d have to be very far away from it,” O’Hara says. “Now assuming this Matrioshka Brain can convert the full output of the sun it encapsulates into antimatter, assuming an efficiency of 10%, then it would generate 67 billion tons of antimatter per annum.”
“More than enough to fuel one of these mothers every year.” Sibidé says.
“Almost two per year,” O’Hara says, “although I suspect the emission of its siren song will also cost quite some energy.”
“But that’s supposing this humongous vessel is empty,” Sibidé says, “now suppose it’s carrying cargo? Or passengers?”
“Or both,” O’Hara agrees.
“Yeah,” Sibidé says, “with a volume like that it could carry millions of humans.”
O’Hara does another quick calculation. “Some 600 million if they’re stacked in cryosleep cylinders.”
Sibidé lets out a long whistle. “Then this megastructure is not a Matrioshka Brain — if you’re right — but more like a Matrioshka Converter.”
6. Hitch A Ride
— feel free to enter our transportation vessel —another aliens message says — as it will leave for its next destination in 2 x 1049 Planck Times while it restocks antimatter —
“So we have about twelve days to decide if we join it or not,” Captain Sibidé says, “but how?”
Should they disembark and somehow get into the enormous alien craft? Or could they just park their own spacecraft inside the humongous contraption? The latter seems more practical, and indeed, as they carefully approach the immense interstellar transporter, a hatch more than large enough to let them in, opens.
“Trust them, Captain?” Chief Engineer O’Hara is getting second thoughts, “Once we’re in, we might never get out.”
“This is not the Hotel California,” Captain Sibidé, a historical trivia buff in her spare time, says. “Anyway, a civilization that can produce Matrioshka Converters just to refuel its interstellar vessels is so much more advanced than us, they could have annihilated us at any time they pleased. We have no choice but trust them, at this point.”
As they approach the alien hatch, they see that there’s another cylinder inside with an open hatch, and yet another, and yet another. Cylinders within cylinders, with binary numbers near the hatches, from 0 — the most outer one — to 1, 01, 10, 11, 001, 011, etcetera. Before they get dazzled, an alien message gives an explanation, — please select the centripetal force that fits your species best — followed by the rotational speed for each binary number.
Chief Engineer O’Hara performs a quick calculation: “Cylinder 011 is closest to Earth gravity,” she says, “a tiny bit smaller, which is good for comfort.”
As they take a right turn when they enter Cylinder 011 — indicating they will settle there — another message is sent their way — please select the spectrum which fits your species best — as it lists a binary-numbered range of the electromagnetic spectrum. Again, Chief Engineer O’Hara — science buff that she is — effortlessly selects the one closest to humanity’s visible light spectrum.
They are told to anchor their craft at the flat wall of their selected Cylinder on the aft side, as that’s where the acceleration force will be until they reach 99% of lightspeed. Also, they receive more information about the huge vessel — Captain Sibidé dubs it the ‘Interstellar Transporter’ — and more request, such as ‘your preferred volatiles to replenish your sustenance supplies’, ‘your preferred day/night cycle (if applicable)’, and the opportunity to spend most of the trip ‘in stasis’ — meaning they won’t age. They’re given ways to traverse the huge craft once the entry hatches are closed and sealed for the big trip, with special emphasis given to a place marked as the ‘Preparation Room’ — basically the innermost Cylinder — which will only open once they reach their destination, whatever that is (as that particular info is not forthcoming).
They’ve entered and settled themselves well in time. Eleven days later, their Interstellar Transporter is ready for take-off.
— transportation vessel Galaxy 17D78400 Arm 6 Section 42 is about to take off — the alien communicator announces — be sure not to stray beyond its aft border as this will expose you to the drive’s gamma rays, and do not stray beyond its forward border as this will expose you to its intense electromagnetic field —
The acceleration to 99% of lightspeed will be that of the species with the lowest preferred centripetal force, they are explained, and since they are the only ones, the Interstellar Transporter takes off with about one G. It will take about a year before they reach 0.99% of lightspeed, and that’s when their Cylinder will start rotating, to produce the centrifugal force that will simulate their preferred gravity. As such, the Interstellar Transporter is not rotating, except for the part that generates the intense electromagnetic field at the bow.
“I don’t get it,” Chief Engineer O’Hara says. “What’s the point of this fast-rotating, wildly twisting electromagnetic field? So close to lightspeed it will only increase the vessel’s drag.”
“Some things,” Captain Sibidé says with a dramatic, hollow voice, “are not meant to be known by mere humans.”
“Oh bullshit,” O’Hara says, rolling her emerald eyes, gently stomping Sibidé’s shoulder with a loving fist, “and you know it.”
“Well, you’ve got plenty of time to think up some hypotheses,” Sibidé says, her deep brown eyes twinkling. “Don’t make them too esoteric.”
7. Road to Nowhere
They travel to three more Matrioshka Converters, each stationed in dark places where previously sunlight used to shine, before the local sun was enveloped. After Captain Sibidé and a few other volunteers tried out the alien stasis and emerged fine from it, they’ve all used it, with no ill effects. The Interstellar Transporter refuels, but doesn’t seem to be picking up other aliens, much to the disappointment of Captain Sibidé.
“Maybe that’s a good thing,” Chief Engineer O’Hara says. “They might be hostile.”
“How could they?” Captain Sibidé truly wonders. “In the view of such immense wonders? Impossible.”
“I suppose so,” O’Hara says. “Anyway, I’ve been thinking.”
“Do you ever do anything else?” Captain Sibidé says, then kisses O’Hara’s forehead as frowns begin to form. “Do go on.”
“If these godlike aliens, or machine intelligences, or whatever is behind the Matrioshka Converters and the Interstellar Transporters, have truly seeded this galaxy, or the whole Universe with them,” O’Hara says, “then …”
“Then what?”
“That would explain the mystery of dark matter,” O’Hara says, looking smart.
“I thought sterile neutrinos accounted for that?” Sibidé says.
“Only for about two thirds of it,” O’Hara says. “This might account for the other third.”
“Okay,” Sibidé says. “Then what about dark energy?”
“Hey, I can only do one breakthrough at a time.”
“That’s fine,” Sibidé says, winking one eye. “We wouldn’t want your head to explode.”
8. Terminal — Local Nexus
— approaching Terminal: Local Nexus — the alien communicator announces at the end of another multi-lightyear trip — everybody please awaken —
Finally, they arrive at a place that does glow in the dark, and quite spectacularly at that.
Viewed from above, it looks like a rotating vortex, shimmering like a barely contained maelstrom of force fields, crackling like a primordial explosion about to happen, the eye of a galactic hurricane. From the side it appears like a perfectly curved funnel, its converging end disappearing out of sight. On the bottom it looks like — there is no bottom to this thing. At least not in this Universe.
“By all the engineering miracles of the Universe,” Chief Engineer O’Hara says (her way of cursing), “another wonder I never expected to see: a wormhole.”
“A gateway,” Captain Sibidé says. “So where does it lead to?”
“Wormholes are inherently unstable,” O’Hara says, ignoring Sibidé’s question while thinking things through. “It needs a constant supply of exotic matter.”
“If these godlike aliens, or extremely advanced machine intelligences can turn whole suns into gas stations,” Sibidé says, “then keeping a wormhole open should be well within their means.”
“So that’s what the madly twisting and fluctuating electromagnetic field was for.” Chief Engineer O’Hara says, happy to unravel another conundrum. “It was harvesting the exotic matter that occurs naturally in the vacuum of space.”
— welcome to the Local Nexus: Exit Portal from this Universe — the alien communicator declares — all those willing to venture into the beyond, please gather at the Preparation Room —
9. Don’t Look Back
“The way I see it,” Chief Engineer O’Hara says, “it’s a giant escape hatch into another Universe.”
“An escape hatch?” Captain Sibidé says. “What’s so bad about this Universe?”
“Maybe nothing much right now,” O’Hara answers, “but in the extreme long term it becomes uninhabitable, either tearing itself apart through a Big Rip, or crushing everything in a Big Crunch. And in the unlikely case that it settles into a solid state equilibrium, then all stars will burn out and entropy will smother life.”
“Well, we can go through this inter-Universal Rabbit Hole,” Captain Sibidé says, “supposedly to a place where the grass is greener, or at least more sustainable.”
“I’m scared,” Chief Engineer O’Hara admits. “I can take the strangeness of deep space, the mysteries of the Galaxy. But this … this is just a step too far.”
“Nobody’s forcing you,” Sibidé says, “but why stay? The answers are there,” she points towards the raging wormhole, barely kept in check by the incoming exotic matter, “beyond this horizon.”
“I’m just different than you,” O’Hara says. “I can only take so much weirdness. Your curiosity is truly insatiable: of course you must go. But I have another mission.”
“Which one?” Sibidé likes to know. “Weren’t we supposed to get to the bottom of this?”
“What you’re about to do, it looks very much like a one-way trip,” O’Hara says, “and somebody’s gotta report our findings back home. That’ll be me.”
“And live without the greatest question ever still unanswered?” Sibidé says, smiling benevolently, knowing exactly what O’Hara means.
“Humans have been doing that since time immemorial,” O’Hara says. “I can keep it up a little bit longer. More importantly, I can tell countless others where to find the answer.”
“True,” Sibidé says, nodding with vigor, “humans will — understandably — believe a report from our own well above an alien message, no matter how inviting. Take care on your way back.”
“I will always love you, wherever you go,” Chief Engineer O’Hara says as she gives Captain Sibidé a final hug.
“I will always love you too, wherever I’ll be,” Captain Sibidé says as thick tears roll over her ebony cheekbones. “Get home safe.”
“Godspeed,” O’Hara says as her eyes mist over, “and don’t look back.”
Captain Sibidé and the other crewmembers who volunteered enter the Preparation Room that’s bathed with a glowing blue light, like ghosts in a transformational machine. After a few seconds, their shadows disappear and they’re gone.
10. The Universal Empath
Space: the ultimate deathtrap. These are the endeavors of the Universal Empath. Its continuing mission: to produce interstellar infrastructure, to invite new life and new civilizations, to boldly take them where no one could go before.