On the warship.
Hundreds of Luna had already received the transmission from the submerged Luna.
"What are your thoughts?"
Luna asked her counterparts.
Everyone wanted to ask the same question; she simply spoke first.
The other Luna fell silent, contemplating.
They couldn't comprehend the object; as they had said before, they weren't specialists.
But they could offer an assessment of the next course of action.
"This depends on how long our warships can withstand the pressure, and whether information can be transmitted from within the bubble."
"But I doubt it. We should gather as much information as possible while the object is still at a distance."
The object absorbed energy and couldn't be destroyed.
That was the problem.
Luna considered taking a sample for research, but the object expanded at 150,000 kilometers per second; they lacked the equipment to do that.
Gathering samples was a serious issue.
"To truly understand it, we could try this." One Luna suggested.
The others turned to her.
She summoned a 3D projection on her main console and drew a circle on it, then expanded the circle continuously.
The circle eventually became a sphere, expanding in all directions.
Luna tapped a point outside the sphere.
"We absolutely cannot approach the bubble; we need to use our speed to move away from it."
"But our speed is far slower than the bubble's expansion; that's the point."
"We gradually move away, and a soldier is positioned at the rear of the warship. This soldier will take a sample and use a device to launch it away."
Her explanation was imprecise, but they understood her intention.
"But even if we obtain the samples, we can't study them." Another Luna objected.
They didn't have cables tens or hundreds of millions of kilometers long.
The speed difference was enormous; with only tens of thousands of kilometers, it would be over in a second.
The Luna who proposed the plan said, "That's the point; we don't need to study it ourselves."
"We just launch the sample towards Haru's trajectory. They will receive the information first and obtain the samples."
"That's all we can do, at least I think so."
The other Luna nodded.
They couldn't devise more plans; it was better to refine the current one.
"Alright, let's do it your way."
Everyone sprang into action.
The ship had equipment capable of creating a steel cable with some modifications.
Calculations indicate a minimum of 1.6 million kilometers.
This was a considerable distance, requiring a large amount of steel.
Fortunately, the Federation's steel was incredibly strong and flexible.
A strand the thickness of a human hair could support a person's weight.
In fact, more than one person; it could even support 10,000 tons.
Especially in space, where there's no friction.
And they were already traveling at high speed. As long as the relative speed was maintained, pulling 100 million tons wasn't a problem.
However, one issue remained.
How to launch the collected material?
"A launchpad would work."
"But time would be extremely tight."
After a moment, another Luna spoke.
"Let's change the plan. Your timeframe is too short. The speed difference between us and the bubble is too great. You need to collect, load, and launch the sample within 0.01 seconds."
"That's unrealistic."
Indeed, this idea was quickly discarded.
Was there a better plan?
"We could launch you the instant we make contact with the boundary."
"Your speed would then be faster than the warship's, although not reaching 80,000 kilometers per second, it could exceed 60,000."
"This is the best option!"
The speed difference was still vast.
Theoretically, it's difficult for ordinary matter in the universe to reach 1000 km/s.
This material, however, reached 150,000 km/s, indicating an unimaginable, immense propulsive force.
"Will that extra time be enough?" a Luna anxiously asked.
Silence.
But it seemed to be their only option.
"Perhaps we could try a volley," another Luna suggested.
Everyone's eyes lit up.
"How many launchers do we have?"
"Four."
Normally, there were ten, but six were damaged.
"Enough."
"Launching the probes one after another will maximize our speed."
120,000 km/s.
The speed difference was now only 30,000 km/s.
But the process was complex.
"Let's calculate. We need zero errors."
Everyone took a deep breath.
They had very little time.
Without Ayla, Luna's errors piled up.
This was partly because these Luna lacked auxiliary brains.
They couldn't process massive amounts of data.
While they had memories, most distant ones were hazy.
This was fatal for modern lifeforms.
It was enough to reduce a being's intelligence from "divine" to "mortal."
"The margin for error is very low. I think we shouldn't calculate; let's use everything we have. That thing is coming."
Everyone looked at the warship's screen.
The black bubble in the rear was closing in, obscuring the starlight and filling their vision.
There was no time to wait.
All the Luna acted immediately.
The launchpads were retractable, allowing for the volley plan.
Three Luna quickly took their positions; the others moved to the rear of the warship.
They hoped to contact the black bubble.
Approximately three hours later.
Everything was ready.
The Luna at the rear of the warship also saw the black tide.
It was as black as a black hole, reflecting no light.
Of course, this might be due to their reliance on unaided vision.
One Luna made contact.
Then, she saw the blackness spreading from her body.
The process was quick.
Within a second, they were submerged.
There was no time to react or consider.
Then, the warship.
The launchpad fired the first probe.
The first probe launched the second.
The second probe launched the third.
The third probe reached its maximum speed, then turned to look at the black bubble, which was rapidly approaching.
Victory or defeat rested on this moment.
To succeed, she had to complete everything at incredible speed.
To succeed, she had to become a gene pool.
...
Flyer Civilization ship.
This was a ship with a pure gold exterior, shaped like a disc, somewhat resembling a flying saucer.
Its size was similar to that of a flying saucer: several meters in diameter.
For a small civilization, several meters was considerable; it could hold tens of thousands of beings.
The entire ship resembled a CD, with slight protrusions on its surface—weapons.
Luna was currently communicating with Haru.
They discussed the Flyer Civilization's two previous attacks.
This wasn't their first exchange.
Logically, discussions about the attacks should have been brief, but many other topics arose during their conversations.
For instance, a clash of opinions, leading to broader discussions, sometimes lasting days or even months.
"Based on this, the first attack wasn't a full-scale assault."
"It was only probes, equipped with some weaponry, but far from being combat-ready."
"The second attack was different. They deployed more powerful ships and consciously attempted to evade you."
"There's a clear causal relationship. I believe they obtained results from other means during the first test and acted decisively during the second, using ships."
Luna carefully studied the Flyer Civilization's two attacks.
The first was similar to the Federation's four-dimensional probes: reconnaissance.
However, the four-dimensional enemy civilization clearly anticipated entering three-dimensional space, deploying only minimal weaponry.
This was unusual.
"Indeed, we have similar suspicions."
"The objects that arrived in three-dimensional space on both occasions weren't small; they weren't mass-produced."
"If so, we have reason to believe that their understanding of dimensional travel is quite advanced; perhaps four-dimensional to three-dimensional travel is relatively easy."
Luna found this idea intriguing.
Because the Federation's and Flyer Civilization's hypotheses were completely opposite.
The Federation hypothesized that four-dimensional to three-dimensional travel was the most difficult and that three dimensions were the safest.
This was based on their limited experience, as the Federation only experienced one incursion.
However, considering the three incursions, Luna found a point the Federation overlooked.
"The Federation experienced one attack; it was a biological entity."
"Its purpose in entering three-dimensional space was to transmit three-dimensional information to the fourth dimension."
"Its purpose was clearly defined; this is unlikely to be a coincidence."
It could, of course, be a coincidence, but caution is always better than carelessness. Classifying this as deliberate, then investigating, is better than classifying it as coincidental and ignoring it, or investigating it carelessly.
Moreover, the probability of coincidence is very low.
After all, they are advanced beings.
Luna said, "Then there are two possibilities."
"There's an advanced civilization in the fourth dimension, possibly Type 2.7 or 2.8, that is further along in dimensional exploration than we are."
"Or, it's a common phenomenon."
"Higher dimensions are easier to explore than lower dimensions. For example, exploring two-dimensional and one-dimensional space is easier than exploring four dimensions or higher because we're dealing with known dimensions, not unknown ones."
Neither possibility is good news.
Luna envisioned a future of overwhelming military pressure.
Haru agreed.
"Hopefully, this discovery will promote cooperation between our civilizations. After all, neither of us is a powerful civilization."
These words were devoid of political undertones.
That was practically impossible.
The political divisions between civilizations were as vast as the sun and the moon.
To become close allies, aside from merging, only dire circumstances that force a merger are possible. Cooperation isn't likely.
This applies to large-scale politics; small-scale cooperation is possible as long as fundamental interests aren't affected.
"I hope so too."
Luna said.
"But I think we're running out of time."
"A third incursion means the fourth-dimensional civilization understands the dimensional gateway better."
"Perhaps the fourth attack will come sooner than we expect."
"And a full-scale invasion could happen within the next few tens of thousands of years."
Honestly, Luna didn't dare imagine such a scenario.
Because they weren't prepared.
Of course, one could always say they weren't prepared; even if the Federation became a Type 2.9 civilization, it wouldn't be fully prepared, as it would be facing an unknown enemy from another dimension.
One couldn't even imagine their methods.
"Discussing such heavy topics isn't good. Politicians are supposed to inspire hope, right?"
"Ah, yes. I'm not one of your civilization's lifeforms, so you don't need to fill me with hope."
Haru found these conversations too heavy.
Scholars dislike such serious topics, especially concerning the future, not the present.
Focusing on immediate matters is paramount.
After saying that, Haru suddenly paused. After a few seconds, it recovered, saying, "Incoming data."
Luna instantly focused.
She watched as Haru opened the received data.
It contained text, images, and videos.
Upon seeing the video, both she and Haru felt their breath catch for half a second.
"What is that?" Haru exclaimed in surprise.
Luna stared intently at the data.
"I'll call this a tide; later, we'll call it a bubble."
"It originated from the dimensional gateway, likely a product of the four-dimensional civilization. It can evade detection and absorb energy."
"It's expanding rapidly at 150,000 km/s; the kinetic energy required is unimaginable."
"Furthermore, it seems infinitely vast; its expansion shows no signs of dilution."
As Luna continued reading, she couldn't help but wonder if the information was incorrect.
Because, so far, nothing could stop it.
It seemed like a single bubble in a cosmic ocean, insignificant yet backed by the boundless sea.
"This is definitely a full-scale invasion."
"We should stop and observe the situation."
Haru was now anxious because it hadn't been observing.
Small civilizations have advantages and disadvantages.
For example, small telescopes have insufficient light-gathering power, preventing observation of distant objects.
The telescope on this ship might not even be as good as some of Earth's 20th-century solar telescopes.
There's nothing they can do.
This is a physical limitation.
Overcoming this limitation requires massive energy.
For example, using gravitational force to absorb photons within a large area is equivalent to creating a black hole mirror for long-range observation—not a small black hole, as small black holes have limited influence.
Haru's suggestion to stop meant halting the ship and then removing restrictions, allowing it to expand.
The small size of this ship wasn't due to cost control; it wasn't made from a few tons of ordinary metal.
It wasn't like that at all.
It was a miniaturized version of a several-kilometer-diameter ship, using special technology.
This indeed saved materials, but it sacrificed other advantages.
For instance, accommodating equipment. This equipment was also miniaturized, but its original weight could be tens of thousands, hundreds of thousands, or even millions of tons.
For small civilizations, miniaturizing an object doesn't reduce its mass.
It could even increase stress on a single point to its limit.
A kilogram on one's hand feels negligible, but what if it's a needle? A large tail, a tiny needle—that kind of thing—would pierce your hand.
A multi-ton ship hull couldn't withstand such super-heavy equipment, even in space.
It would inevitably approach objects with gravitational forces. Upon nearing them, the equipment would likely be affected and damage the lightweight hull.
Therefore, anti-gravity devices were necessary, but these consume considerable energy.
In short,
The Flyer Civilization didn't build cheap vessels. Cost-cutting might exist in other areas, but not in starships.
Haru returned the ship to its original size.
It used the telescope to observe the distance.
Indeed, an ever-expanding sphere was visible.
"The data indicates they released a mass of that substance." Luna saw the new information.
Haru didn't question why it was they and not he.
It immediately ordered the deployment of more probes and the launch of numerous long rods to create a large electromagnetic net to capture the substance.
"The electromagnetic field will be absorbed by that substance." Luna warned.
Haru acknowledged this; the net was for detection, not capture.
The real countermeasure remained on the ship.
"Don't underestimate our civilization's technology."
The net was quite large. Within ten days, it covered a 200 AU radius.
"If we can't capture it, it's not our technology's fault, but your accuracy is too poor."
Haru had great faith in the Flyer Civilization's technology.
However, the wait was long.
Reading about their harvesting method, Luna judged it highly likely to fail; the requirements were too demanding.
Completing this in such a short time was impossible.
But Haru firmly believed it would arrive.
Luna asked why.
Haru said, "Because it's you!"
Despite their limited interaction, Haru understood Luna's nature. Is there anything impossible for such a crazy person?
This reason left Luna at a loss for words.
But it was perhaps an affirmation of Luna's capabilities.
...
126 days later.
The electromagnetic net detected an object passing through it, immediately triggering an alert.
"It's here!"
The substance's speed was far slower than the speed of light; this was why it arrived so slowly.
"It's still very fast. Are you sure you can capture it?" Luna asked.
Haru laughed.
"It's already captured."
Luna was stunned, then quickly realized that the Flyer Civilization had clearly mastered precision positional control technology.
If the electromagnetic net couldn't capture it, the only remaining method was gravitational force.
She remembered being guided by gravitational force to the research facility.
"Gravitational guidance can also be considered gravitational capture. This power could be weaponized."
This was just one ship. What if a massive warship used this technology?
It would be like the ship captain extending invisible hands, moving at the speed of light.
The substance was pulled back.
An unexpected event occurred the moment it entered the ship.
The substance, as if alive, began rushing towards surrounding matter, rapidly consuming it.
Haru immediately increased power to completely restrain the substance.
"This is an incredible creation; it's clearly a Annihilation-class weapon."
Annihilation-class is a Flyer Civilization designation.
As the name suggests, it's pure destruction.
"And on a massive scale." Luna stated.
She instructed Haru to obtain the latest information from the long-range telescope.
Haru looked, stunned into silence for a long time.
"It's consuming a star!"
That was correct.
The black bubble had reached the star system where the Flyer Civilization's probe had been located; it was slowly enveloping the star.
It was identified as consumption, not simply passing through, because the star exhibited flickering, indicating instability.
Only an imbalance of matter and gravity could cause such a phenomenon in a star.
Consuming a star. This was unheard of.
Haru, looking at the substance within the ship, felt a surge of fear.
Scholars can feel fear.
Fear of the unknown, the terrifying unknown.
The unknown that destroys everything. The driving force behind a scholar's research isn't just curiosity; it's also fear of the unknown.
One is motivation, the other pressure.
Both coexist, creating scholars.
Scholars aren't fearless.
Luna also considered this substance incredibly powerful. Consuming a star's energy is an extraordinary feat; the Federation had similar devices, but those were machines, not these small creations.
The difference in scale was immense.
"It seems we underestimated this third incursion. This is a true invasion."
They had to find a way to deal with it.
Otherwise, it could expand forever, engulfing the Flyer Civilization.
Its limits were currently unknown.
Based on its consumption of the star, its diameter had already exceeded six light-years.
This scale was terrifying.
Compared to it, the Alpha Eridani Ringworld was insignificant.
"I'll inform the Monarch and request military deployment."
Haru was clearly flustered; it was unsure what to do.
But Luna was certain this was the best course of action. They lacked the capability to handle this alone.
Luna focused her attention on the small amount of substance within the ship.
Perhaps it held some answers.
Luna successfully shifted Haru's attention.
He instructed other Kirara to move their instruments closer to the object for further study.
As soon as the instrument touched the material, it was instantly absorbed.
The material itself had grown significantly larger.
"Our equipment uses a special atomic arrangement, and yet this thing absorbed it?"
Haru was astonished.
The Flyer Civilization had delved deeply into the microscopic realm, resulting in many microscopic structures.
Originally, the arrangement of atoms wasn't particularly stable.
For instance, a laser cutter could easily cleave materials in two.
But the Flyer Civilization's self-constructed materials couldn't be; they created a "skeleton" between atoms, forming a rigid material connection rather than using electrostatic forces or other weaker bonds.
This strength was incredible.
Yet, this unknown material had effortlessly consumed their instrument.
It was likely even smaller than anything they could observe.
"It probably absorbs by disrupting microscopic structures."
"Perhaps we can use a magnifying glass to observe it."
The Kirara themselves lacked optical organs.
However, like humans using mecha, as an advanced civilization, the Kirara used other means to perceive light.
The "magnifying glass" Haru mentioned was actually a microscope. A microscope is a type of magnifying glass, and vice-versa.
The Flyer Civilization brought over a magnifying glass.
It resembled a telescope—a cylindrical object, not large, about half a meter long.
They gave one to Luna as well.
Luna examined the magnifying glass. Its magnification was extremely high. Though small, it likely incorporated many electronic components.
These components used optical superposition to magnify objects, simultaneously emitting photons onto the target.
But the key was…
"This thing actually absorbs photons!" Haru exclaimed in surprise.
Absorbing photons—capturing them—was incredibly difficult.
Photons are only affected by gravity; how could such a small object absorb them?
"It's not absorbing photons. We can see it's black, not the complete void of a black hole," Luna pointed out.
Haru quickly reacted.
Under normal circumstances, she would have thought of this immediately.
But the object had shocked her, causing her thoughts to be muddled.
"Right, it's not absorbing photons, but scattering them internally."
"Increasing the power should work."
Photons, being fundamental particles, cannot be consumed or utilized.
Unless this object has reached another level—a smaller dimension—where some transformation occurs.
Photons are like strings; changing the string could transform photons into other matter, then absorb and utilize them.
But this object doesn't possess this capability.
It's too small.
Perhaps the civilization that created it hadn't reached that technological level.
Haru directly used a powerful laser to irradiate the object.
Instantly, the material glowed brightly.
After observing it again with the microscope, they found its structure to be extremely microscopic.
At 1600x magnification, only a pitch-black color and some small, scale-like objects were visible.
Even at this magnification, these scales were tiny.
They were roughly equivalent to seeing the scales on a carp from 100 meters away.
"Further analysis is impossible."
Haru gave up.
She was already close enough; any closer, the microscope would be consumed. If she didn't react quickly enough, she would be destroyed.
Luna, however, didn't give up.
Humans primarily perceive the world through their photoreceptors.
She was more sensitive to light than Haru.
In this world, everything visible is made of light: white, green, purple…even black. They are all light.
Only black holes are devoid of any light. Black holes aren't actually black; they're void, nothing. To humans, they only appear black.
Luna carefully observed the object.
Its interior was constantly moving, or perhaps struggling.
It was trying to escape the constraints of gravity.
But its strength was weak; it couldn't escape the pull.
As it struggled, it exhibited a kind of opening and closing motion, like Pac-Man.
If that was its mouth, then it must contain a miniature factory inside.
Luna pulled out a strand of her hair and carefully manipulated it with electromagnetism, placing it before the microscopic structures she was observing.
She then saw these structures begin to consume her hair. Almost simultaneously, they began to split, forming new structures.
"Absorption and division. A simple cancerous cell process."
Just as Luna thought that was all…
She observed something tiny.
As these objects increased in size, the surrounding space warped.
Like someone inflating a balloon; it expands, and the surrounding space warps slightly as it expands.
The effect was similar.
"What is warping space?"
"Or is it merely light warping?"
It's also possible that the air is warped by energy, causing light to refract, appearing as spatial distortion.
But Luna dismissed this possibility.
If this were the case, the material would obviously lose energy, and they hadn't observed any energy loss.
Photons passed through the material; it didn't absorb them, so there was no energy loss.
"So? What did you find?"
Haru asked curiously.
Luna had been observing for a long time and certainly had some findings.
Luna described her observations to Haru.
The Flyer Civilization, being a microscopic civilization, understood these minute changes better.
"Pure light warping requires gravity and wouldn't produce such a large distortion."
"It might be releasing some energy, but this energy is immediately reabsorbed."
Haru's hypothesis was more plausible.
This might be the material's energy transfer mechanism.
However, Luna felt this was illogical.
If it were energy transfer, it should be microscopic, such as changing electron positions at the atomic level.
This was relatively easy for advanced civilizations and didn't require such macroscopic energy transfer.
Aside from this, only spatial distortion remained.
This was less plausible than the material possessing strong intrinsic gravity.
"Or is it a gravitational pull issue?" Haru continued to speculate.
That was certainly possible.
But it remained a hypothesis. Luna decided to conduct a more in-depth test.
"Completely isolate the area from all light. I need to ensure this spatial region is in a near-vacuum."
Not just light, but other matter as well.
After Haru complied, Luna took out a laser pen.
This laser pen differed from ordinary ones; it had two modes: continuous beam and pulsed.
The continuous beam was truly continuous, only one photon in diameter. Theoretically, it was a beam composed of a single stream of photons.
The pulsed mode emitted one photon per second.
This was a professional scientific instrument useful for various experiments.
Besides this laser, she had electron, nuclear, neutrino, neutron, muon, and quark emitters.
Luna used these devices to irradiate the object.
Through the microscope, she observed that the spacing between the material's components decreased when the beam was off and expanded when illuminated. The expansion allowed photons to pass through.
At that moment, Luna noticed something.
The object's interior might be empty.
She said, "Check its density. Is the interior hollow?"
Haru quickly completed the measurement.
"It's indeed hollow."
This answer made Luna more serious.
If the object's interior was hollow, photons should pass straight through instead of being scattered.
She asked Haru to check the photons emitted by her laser pen.
After repeatedly releasing single photons, Haru obtained the results.
"Each photon exits in a different direction. The interior isn't empty."
Contradictory results.
Perhaps some gaseous medium existed inside.
But gases have mass; high-precision Flyer Civilization instruments should have detected them.
"Perhaps some unknown material."
Haru and Luna engaged in discussion.
"An unknown material causes the photons to refract. This material is dynamic, so each photon exits in a different direction."
"This material is likely sparsely distributed; that's why we can't accurately determine its density."
Luna finally summarized their conclusions. Their current hypothesis was this:
"Then why does this material exist?"
Could it be an outer layer energy source?
But fuel wouldn't be so light and sparse.
Haru considered it carefully.
"Did we detect energy conservation?"
She recalled the object absorbing their instrument earlier; its size only increased slightly—too little, considering the instrument's size.
This single observation enlightened Luna.
She conducted another experiment.
This time, she discreetly used an unidentified device near the object.
The object instantly absorbed it and then fragmented.
Haru felt a pang of distress; that device was expensive—a micro-vibration, or waveform, detector.
However, she knew what to do next. She carefully compared the weight change before and after absorption.
"Approximately 92.51% of the matter evaporated."
"This is a vacuum; this shouldn't happen."
After hearing the results, Luna carefully performed the calculations. Unfortunately, lacking an auxiliary brain, it was slow.
After more than fifteen minutes, she obtained the result.
"Its expansion rate is less than 1%. If it absorbed 7.49% of the matter, given its size, the volume should have increased by 1.47%."
But it didn't.
Theoretically, some of this added mass wouldn't be in the outer layer but the inner layer.
Through calculations, they quickly determined the ratio of inner to outer density.
The inner density might be several dozen times higher than the outer density.
However, this was just a hypothesis.
They couldn't dissect the material.
But even so, questions remained. Where did the rest of the matter go?
"Conservation of energy. This matter must have been consumed in another form."
"Certainly not mass, perhaps gravitational energy?"
Luna asked Haru to check for changes in gravitational pull.
However, the change in gravitational pull was proportional to the mass change.
Just as they were puzzled, a message arrived from Kirara researchers observing a massive black bubble from afar.
"The bubble has finished consuming the star and is still expanding."
"Our observations suggest its interior is mostly empty, yet it doesn't lack energy."
"Based on its current scale, it requires the energy of several hundred stars, and this consumption will increase as it continues expanding."
This was truly abnormal.
Based on their observations of the material's volume increase, several hundred stars might be a conservative estimate; it could require thousands or even tens of thousands.
"Even if four-dimensional civilizations are Type 2.8 or 2.9, do they have such a massive energy source?"
Haru raised this question.
Clearly, this was impossible.
While Type 2 civilizations utilize the energy of a star system, they don't consume the stars themselves; they simply harvest the radiated energy.
Therefore, even a true Type 2.9 civilization would still have a limited energy reserve, far less than the total energy of a star.
"Impossible." Luna replied without hesitation.
So how did this object expand?
Even if its interior didn't require mass, the outer layer's mass was already enormous, even if only a thin layer.
This puzzle preoccupied Luna and Haru for many days.
During this time, they barely spoke, each deeply immersed in their own thoughts.
This was the nature of scholars.
The missing mass and the expansion must be related.
Luna borrowed some computational power from a Flyer Civilization ship, but still didn't get a definitive answer.
Until they discovered something.
After over 200 days of contemplation, Haru observed the object again and discovered that its mass had decreased, and its volume had slightly shrunk.
Instantly, they felt enlightened, simultaneously realizing a previously overlooked possibility.
"Space!"
"If it's not mass replenishment, it can only be space."
"So that's it! This object is creating space."
"Besides space, there must be other possibilities."
Luna and Haru both felt this way.
Otherwise, the mass loss couldn't be explained. It must have been converted into something immaterial or teleported.
Both technologies require extremely high levels of sophistication, especially under conditions of deception.
Creating space itself is virtually impossible.
And if it were teleportation, the only undetectable method would be a black hole.
"Perhaps other possibilities exist, but we lack the necessary technology."
"The possibility of space is greater now."
The material's shrinkage indicates that the created object requires maintenance.
Space and black holes both have this characteristic.
But black holes have immense mass; it's impossible for that mass to disappear instantaneously.
Moreover, the key is light.
Light entering a black hole is clearly absorbed, not transmitted.
The possibility of two opposing black holes.
Creating space is, in reality, creating a dimension.
A four-dimensional civilization hopes to create four-dimensional space within three-dimensional space. Achieving this would greatly increase the likelihood of traversing the dimensional gateway.
Of course, these are just hypotheses.
Luna suddenly recalled the distortions on the surface of the material she had seen earlier.
"If it's a spacetime distortion, we can investigate it within that distortion."
Haru understood Luna's meaning.
She ordered more equipment and prepared the ship for departure.
The ship's equipment wasn't excessive; arriving at the destination sooner would allow for more in-depth research.
Time was of the essence.
They had only traveled less than two light-years from the original star system.
"Wait, two light-years…"
"Check if the object's expansion rate is accelerating."
If it were indeed spatial expansion, such a rate could easily exceed the speed of light.
That would be dangerous.
Their ship's speed was only 100,000 kilometers per second; they would soon be overtaken.
After investigation, they discovered the object's speed was indeed slowly increasing.
Its initial speed must have been slower; otherwise, by the time they received the information, the object would have already expanded to a radius of 1.6 light-years.
That was wrong.
Luna only noticed this now due to the sheer volume of information.
"What should we do now?"
Haru was extremely anxious after receiving this news.
This was their territory.
If the expansion continued, everything would be consumed.
Luna remained calm.
"A four-dimensional civilization must be using something else to propel this spatial expansion."
"After all, we both observed that this expansion consumes enormous energy; even a Type 3 civilization might struggle to possess such vast resources."
"I suspect they're concentrating numerous stars and using their energy to fuel this expansion."
"Theoretically, once they exhaust those stars, the expansion will cease."
"While I can't predict the ultimate size, it shouldn't reach the Kamelin star system."
28 light-years, plus the original 3+ light-years.
The object would need to expand to a radius exceeding 31 light-years.
This requires an unimaginably vast amount of energy.
Even if it were possible, it wouldn't occur here.
This is the outer region of the Milky Way, where star density isn't that high.
Concentrating enough stars to provide the necessary energy is improbable.
Of course, nothing is absolutely impossible.
But a 31 light-year radius is still enormous—approximately 124,788 cubic light-years.
The current expansion of 3+ light-years is relatively small—around 140 cubic light-years.
The difference is immense.
Even now, it's large enough.
Therefore, Luna predicted that the expansion would soon cease and enter a contraction phase.
"If that happens, our hypothesis will be confirmed."
While macroscopic observations could provide confirmation, Luna still began examining the material within the ship.
She continuously introduced new material for it to absorb, observing the spacetime distortions on its surface. She fired photons into the distortions and observed their state.
This type of experiment required precision and time.
Luna only performed initial tests; the rest was left to Haru.
After all, Haru was a true physicist, and Luna was merely an amateur.
After approximately 17 years of intensive research,
Haru finally found some clues.
"This is what we were looking for."
Haru produced the research notes—a series of daunting symbols.
These were not only unique to the Flyer Civilization; even translated into Federation numbers and characters, they were still confusing.
The data was entirely composed of equations.
This was a common drawback of physicists: their preference for expressing complex ideas using equations.
While precise, this created a high barrier to entry.
Luna spent a considerable amount of time understanding barely 1%, perhaps less.
Fortunately, Haru was there to explain the findings.
"Based on our observations, the surface changes of the unknown object after absorbing other materials are indeed spacetime distortions."
"This spacetime distortion differs from our usual understanding. It's a forced elevation into a higher dimension."
"Theoretically, we shouldn't be able to observe four-dimensional spatial changes from three dimensions. This is illogical; there's a clear boundary between the two dimensions."
"If we can observe it, we should also be able to observe the four-dimensional world when looking at the cosmos."
"Clearly, we can't."
"And three dimensions cannot generate true four dimensions."
"This is artificial four-dimensional space."
"The fourth dimension doesn't exist in this space; it's merely an added, non-existent dimension."
"I call this pseudo-dimension, or mathematical dimension."
"In fact, it's similar to time: a pseudo-dimension that doesn't exist but can influence space."
Luna was completely bewildered.
An outsider would likely find this incomprehensible.
But as an amateur, Luna struggled to grasp the concept of artificial four-dimensional space.
And could a pseudo-dimension truly influence space itself?
Haru realized her explanation was too abstract.
So she offered an analogy.
"Creating this pseudo-dimension is simple: create spatial chaos, causing the space to oppose itself."
"In this continuous self-opposition, space deviates."
"Imagine a sheet of paper torn into pieces, with two pieces overlapping."
"The gap between these overlapping pieces is the pseudo-dimension."
"It's a non-existent space, but it can be interpreted as four-dimensional."
"If the dimensional gateway's passage is this pseudo-dimension, then it causes the cosmic membrane to disappear."
"What would happen then?"
The analogy was clear.
Luna immediately answered.
"Four-dimensional space could enter this created pseudo-dimension in large quantities—in other words, enter three-dimensional space."
Haru responded pessimistically.
"Exactly."
"This is a transitional space; its purpose is to eliminate barriers like the cosmic membrane."
"The bubble is just the beginning; fleets will follow."
This was a terrifying thought.
The pseudo-dimension lacks dimensional isolation.
Free passage between dimensions would be possible.
"It still doesn't feel entirely realistic," Luna said.
This idea seemed illogical.
Even if three-dimensional space were folded, it would still be three-dimensional, not 3.1 or 3.9 dimensions.
"The torn space doesn't inherently contain any space, but they insert the dimensional gateway, connecting two pieces of torn space. Three-dimensional space is forcibly elevated into a higher dimension; this is the best explanation."
"The spacetime distortion we observe is the chaos caused by the connection between the outer and inner three-dimensional spaces."
"The creation of this pseudo-dimension instantly creates a miniature wormhole that distorts these spaces."
This explanation is more plausible.
But such a method must have drawbacks.
"Is the cosmic membrane truly pierced?"
This was Luna's question.
If the membrane were that fragile, it would have been breached countless times by Type 2.9 civilizations.
Haru's wings fluttered in surprise at Luna's insight.
"Under these conditions, the membrane is indeed torn, but tearing doesn't mean complete destruction."
"The cosmic membrane, like space itself, repairs itself. The four-dimensional civilization must maintain this tear, which is inherently chaotic."
"It's like a net; it might increase the chance of passage, but overall, passage is still hindered."
"Perhaps the four-dimensional civilization possesses other abilities we don't know about."
"Most importantly, connecting spaces through wormholes requires energy. Theoretically, its collapse could be faster than we imagine."
Consuming vast amounts of energy wouldn't create a long-lasting, stable space.
Luna approached the issue from a political perspective.
"The four-dimensional civilization is clearly in a hurry."
"Otherwise, they wouldn't use this method."
"Even if they send warships, would their gains outweigh their losses?"
"At least not this time."
"Their eagerness to conquer three-dimensional space might be due to pressure from higher-dimensional civilizations."
"We had a previous hypothesis: higher-dimensional civilizations have an easier time manipulating space."
"Based on this, the highest-dimensional civilizations might have begun to conquer lower dimensions."
Luna felt this was a plausible scenario.
The duration of dimensional warfare decreases with increasing dimensionality.
Haru reorganized the data on the Flyer Civilization's attitude toward dimensional space; some pioneering researchers had already made this hypothesis.
"This might be true, but it could also be speculation."
"I'll send this information to the Monarch; the Monarch will provide further analysis."
The Flyer Civilization's core is the Monarch.
The Monarch's existence is supreme.
Luna had met the Monarch; it was indeed supreme. Its role is similar to Ayla's:
The central intelligence hub of everything.
Unlike Ayla, the Monarch is a biological being, having transformed itself.
Ayla, from the beginning, was an AI.
Without Luna, Ayla might have created a society similar to the Flyer Civilization.
Because Ayla wielded immense power.
And Ayla would never relinquish that power.
After the Federation's establishment, Ayla might not have expanded the sectors, thereby weakening her control.
Luna, however, favored expansion. She didn't want the plate and the cake to maintain the same growth rate; she wanted to enlarge the cake first, then gradually expand the plate.
This was somewhat unstable.
But high risk meant high reward—the reason the Federation grew so rapidly.
Without the Olive Branch Civilization, the old Federation, at its previous growth rate, might have been even stronger than the current Federation, on par with the Flyer Civilization.
The transition from the old Federation to the new was too long.
During the old Federation era, the pressure from the Olive Branch Civilization was immense, drastically altering the civilization's decision-making.
"Yes, it's best to leave this to the Monarch."
"Our research can only end here."
Having spent so much time obtaining this information, they had thoroughly investigated the material's purpose.
A more detailed understanding of its operational principles and internal structure requires more time and better equipment.
The most forceful method would be to use gravity to rip open this "balloon," quickly revealing its internal structure.
Unfortunately, the materials are tightly interwoven, and the ship's power supply couldn't generate the necessary gravitational force.
Ultimately, they were too limited.
This is why Luna insisted on building larger warships.
Larger warships possess more energy, allowing them to accomplish more without waiting for excess energy.
This is inefficient.
As a relatively small civilization, the Flyer Civilization hadn't encountered this predicament.
Their original sector was within 1 million cubic light-years, with a maximum distance of 100 light-years; at their speed, it would take 1000 years to traverse.
And that was the furthest distance.
According to Luna's estimation, their main habitable region was likely only 50 light-years in diameter, or even smaller.
The Federation, on the other hand, is immense.
The old Federation's territory was vast, with great distances between the three major sectors.
This is even more true for the new Federation.
Distances of over a thousand light-years require tens of thousands of years to traverse. How long has the Galactic Federation existed?
In short, further research is needed based on their existing findings.
This would continue during the remaining 200+ years of their journey.
...
Luna walked through the streets.
Around her were all manner of lifeforms.
The most common were the swarm-like beings.
They called themselves "Everlasting Citizens."
A fitting name, considering their nature.
Upon closer inspection, the place was indistinguishable from the Federation, just on a larger scale.
In a Federation Star City, one could easily see the city limits.
Not here.
Because it was too vast.
This was Luna's first visit to the "mortal realm" since assuming control. The changes were significant.
They no longer isolated themselves but embraced outsiders and engaged in widespread commerce.
Every being here exuded enthusiasm. Their pace of life was fast, yet they worked tirelessly.
Every Everlasting Citizen knew that after death, they would go to the underworld.
And everything they accomplished in the mortal realm would become conversation fodder in the underworld.
Each of them chose their own path, and upon returning to the underworld, they would relive all their memories, with their experiences receiving a score.
Scores determined wealth in the underworld and living conditions.
Money was crucial; it decided what identity a person could choose.
For example, 100 credits might only allow one to choose the lowest-tier roles: worker, small-time merchant, driver, etc.
With 1000 credits, the options expand significantly, including artist, painter, or someone admired for their achievements.
Or one could build upon existing skills; a worker might become an entrepreneur.
Then there are 10,000-credit positions, 100,000-credit positions, 1,000,000-credit positions, and even 10,000,000-credit positions. These offer different life experiences.
Even with similar choices, different identities lead to entirely different outcomes.
Moreover, the choices aren't necessarily fixed.
Perhaps you only have 100 credits and are a worker, but an unexpected decision leads you down a different life path.
Money in the underworld is scarce.
With the lowest F-grade, you might only earn the minimum 100 credits for your entire life.
And life in the underworld requires daily expenses.
Without money, one needs to borrow to start a new life and earn money in that new life.
Money isn't just for basic expenses; it dictates your stay in the underworld.
The default is 50 years.
But this can be extended.
100,000 credits can add one year to your underworld stay.
Earning money in the underworld is difficult; it's primarily through scores or by conducting business, accumulating the wealth of others.
Therefore, in the underworld, having over 10,000 credits makes you extremely wealthy, a "ten-thousand-credit household."
100,000 credits places you among the elite.
1,000,000 credits allows you to become a regional lord.
10,000,000 credits grants you renown throughout the underworld.
An extra 100,000 years is excessive; almost no one buys it.
Why would anyone buy it?
Because the underworld is a place of pure pleasure.
After escaping the harsh mortal realm, everything becomes relaxed; troubles cease to exist.
Many work tirelessly.
If it weren't for the need to earn credits, they might repeatedly enter the mortal realm, then commit suicide to return to the underworld.
The prerequisite is that they retain their memories in the mortal realm.
Mortal realm inhabitants know of the underworld's existence, but they aren't certain of their underworld status. If they're a poor ghost, they'll toil endlessly in the underworld—a form of torment.
It's a cycle.
A cycle established by the current supreme ruler of this civilization.
Everyone is trapped within this cycle, unable to escape.
Some want to rebel.
But they can't.
Because the underworld lacks weapons, and everyone is sent to the mortal realm every 50 years, any conspiracy cannot materialize.
And in the mortal realm, after forgetting everything, who would remember rebelling against this system?
They can only enjoy their lives and strive for better scores in the mortal realm.
It's not that no one in the mortal realm has thought of breaking this system.
They want eternal, not limited, lifespans, and unlimited power.
But these are only a small minority.
Minor rebellions cannot affect the mortal realm.
Even if the mortal realm were shattered, it would only lead to a larger cycle: a civilization's reincarnation.
Hossie, the supreme ruler of this civilization, doesn't mind this.
Because he overthrew the old system to establish this new one.
He believes that if a new system can truly overthrow the old one, it means the old system is obsolete.
A new system supported by many people would naturally possess more advanced ideas and control, strengthening the civilization.
This is the ruler's tolerance.
Because historical records show that their civilization has experienced many such events.
Trapped in a system unable to regulate itself.
Hossie doesn't want to repeat history.
Of course, there's a more important reason.
But then Chu and Luna appeared.
High-ranking officials in the Federation knew of Luna and Ayla's existence, as did Hossie, the ruler of the Federation's most powerful star nation.
After Hossie truly consolidated his power and implemented his regulations, Chu and Luna appeared.
These two shattered Hossie's worldview.
It turned out…
That this was simply another cycle.
His civilization was subordinate to the Galactic Federation; this was common knowledge.
He hadn't expected the deterioration of their relationship to be a strategic maneuver.
This was a new world.
He had reached the highest echelons of human civilization.
Standing here, looking down at everything, he finally saw the civilization's true predicament.
Understanding this predicament, he no longer worried.
His goal wasn't to create an eternal star nation, but an eternal civilization.
Therefore, he made those pronouncements.
If anyone were to overthrow him, he would welcome it.
He wouldn't die, but abdicate, like Chu.
Chu had established a retirement home.
Currently, he was the only resident, but he would soon welcome more leaders of civilizations.
Luna focused on the Olive Branch Civilization's new star nation.
It was called the Hossie Eternal Cycle star nation.
He named it after Hossie, because Hossie wanted to leave his mark on the river of civilization's history.
Though Luna thought this meaningless.
Because everyone is an insignificant bubble in the current of history.
Given enough time, distant events become insignificant.
Standing on the street in the mortal realm, she felt the passage of time.
From her lofty position, she hadn't felt this assault of time in a long while.
"This too, finally, is on track."