The Village-Class starship continued to accelerate, only coming to a stop after reaching three times the speed of light.

Three times the speed of light was the maximum speed Xiao Yu could currently achieve.

Fifty years later, the radius of the Four-Dimensional Barrier had shrunk from ten billion kilometers to seven and a half billion kilometers. This meant that, starting from the center of the star system, at the speed of this Village-Class starship, it would take only two and a half hours to traverse that immense distance.

The curvature drive method was fundamentally different from conventional travel. The biggest difference was that in conventional flight, after the initial acceleration phase, a ship could rely on inertia to continue moving, saving a large amount of fuel. But with the curvature drive, since the ship’s motion was technically zero, there was no inertia to exploit, meaning it couldn’t coast on momentum. This meant that during the entire journey, the Elemental Decay Engine had to run continuously to provide power to the curvature engine.

This resulted in energy consumption that was vastly higher than conventional travel. Without elemental decay technology, curvature travel would have been nothing more than an illusion, utterly impossible to realize.

This feature had both advantages and disadvantages. The disadvantage was, of course, the excessive energy consumption. The advantage was a revolutionary improvement in maneuverability.

A starship traveling via curvature drive could accelerate from a standstill to light speed within ten seconds, or decelerate from light speed to a complete stop within the same time frame.

To put it less precisely, the maneuverability of Xiao Yu’s starship was tens of thousands of times better than before.

One hour later, this starship, propelled by the curvature drive, arrived at the edge of the Four-Dimensional Barrier.

Once it entered Faster-Than-Light travel, matter disappeared from all wavelengths. Whether visible light, ultraviolet light, or infrared light—it could no longer be seen. Through research, Xiao Yu concluded that this was because redshift became so extreme that the light shifted out of detectable frequencies. However, by measuring spatial distortion levels, Xiao Yu could still pinpoint the starship’s position with precision.

Likewise, during Faster-Than-Light travel, due to the extreme blueshift, all external light became completely invisible as well.

In other words, during Faster-Than-Light travel, the starship was completely isolated from the outside world.

This brought a certain level of danger to Faster-Than-Light travel, because during the journey, the starship could not detect whether there were obstacles ahead. For short-distance travel, this was manageable, but for long-distance journeys, there was a real risk of accidental collisions, such as crashing headlong into a star or a planet.

In fact, a starship in Faster-Than-Light travel was not incapable of receiving or emitting light. It was just that the extreme redshift or blueshift made it impossible to detect such light. To address this, Xiao Yu was already conducting research, trying to develop an instrument that could restore light frequencies, allowing him to detect external information even during Faster-Than-Light travel.

However, at this stage, that device had not yet been successfully developed, and Xiao Yu needed to continue his tireless research and invest more effort to create it.

After the starship arrived near the Four-Dimensional Barrier, Xiao Yu’s full attention was focused there.

Because of his lack of understanding of the Four-Dimensional Barrier’s properties, Xiao Yu didn’t know how to break through it. But according to his hypothesis, Faster-Than-Light travel might very well pierce it. Now was the moment to test whether his guess was correct.

“Collision will occur in five seconds. Five, four, three, two, one…”

In the view of the spatial distortion detector, the Village-Class starship suddenly vanished.

“Did it succeed?” Xiao Yu thought nervously. He immediately used Superluminal communication to command the starship to exit Faster-Than-Light travel and begin scanning the external environment with its onboard instruments.

What he saw was a void, completely empty, with nothing at all.

“Where is this?” Xiao Yu wondered blankly. “Could it be that Faster-Than-Light travel breaches into another space? That’s a bit too far-fetched…”

Xiao Yu piloted the Village-Class starship to continue scanning, and soon, within the spatial backdrop, a faint reddish barrier caught his attention.

It was an enormous red barrier, so vast that it filled the entire view of the detection instruments.

Xiao Yu’s heart gradually sank to rock bottom.

The Village-Class starship’s instruments adjusted direction, and sure enough, they detected the massive red giant. After the starship sent out a burst of radio waves, the satellites scattered throughout the star system used the signal to quickly triangulate its position.

The result was clear: this Faster-Than-Light starship had still not broken through the red barrier. Like every other ship before it, upon contact with the barrier, it had been randomly teleported to a point between one billion and 1.1 billion kilometers from the central star.

The experiment proved that Faster-Than-Light Travel could not penetrate the Four-Dimensional Barrier.

“I should have realized it sooner. Against a Four-Dimensional Barrier, Faster-Than-Light Travel just won’t cut it,” Xiao Yu muttered to himself. “If Faster-Than-Light Travel alone could break through the Four-Dimensional Barrier, then the Four-Dimensional Shield would be meaningless. After all, a Level 4 Civilization that masters Faster-Than-Light Travel could likely also develop Faster-Than-Light kinetic weapons. If the shield couldn’t defend against Faster-Than-Light attacks, then the value of the Four-Dimensional Shield would be far less than that of the Force Field Shield.”

“So, how exactly can I break through the Four-Dimensional Barrier?”

Xiao Yu fell into a state of confusion.

Elemental Decay and Faster-Than-Light Travel were Xiao Yu’s greatest technological breakthroughs of the past few centuries. And it was foreseeable that, for the next few centuries, perhaps even millennia, he would not achieve any other major breakthroughs.

“If Taihao was truly benevolent toward me, it wouldn’t have created a barrier that a Level 4 Civilization’s technology couldn’t break through. In other words, if we assume Taihao is benevolent, the technology to break through the Four-Dimensional Barrier must exist within the tech framework of a Level 4 Civilization. But if even Faster-Than-Light Travel doesn’t work, what else could it be? After all, Faster-Than-Light Travel is the most distinctive hallmark of a Level 4 Civilization.”

Xiao Yu pondered slowly. “Could it be Elemental Decay Bombs? Or the Material Disintegration Beam? Or maybe bombarding it with a massive number of Faster-Than-Light kinetic weapons?”

At that moment, Xiao Yu felt like he had suddenly lost his sense of direction.

Breaking through to a Level 5 Civilization within a short period was impossible. Not only that, but within the remaining 150 years, achieving another significant technological breakthrough was also unlikely. This meant Xiao Yu would have to rely on the technologies he already had to attempt to break through the Four-Dimensional Barrier.

But… if even Faster-Than-Light Travel couldn’t break through, what kind of technology could?

Xiao Yu thought in bewilderment. “This is something that can only be tested slowly in the future. I just hope I can find a solution within 150 years.”

The radius of the Four-Dimensional Barrier continued to shrink. It was like a noose tightening around Xiao Yu’s neck. The moment it tightened to the point where he could no longer breathe would be the moment of his demise.

But Xiao Yu quickly discovered that he had overlooked something.

He had missed a critical issue all along.

By chance, the temperature detection instruments on one of the ships found that the temperature in interstellar space was gradually rising.

Before the appearance of the Four-Dimensional Barrier, within this star system, the temperature at a distance of two billion kilometers from the central star was 137 degrees. At seventy billion kilometers away, the temperature was minus 185 degrees.

The temperature referred to here was not merely a theoretical physical quantity, but a real, measurable temperature.

But now, that temperature had changed. Xiao Yu saw that at his current location, the temperature had silently risen from 137 degrees to 145 degrees, and at seventy billion kilometers from the central star, the temperature had already climbed to minus 150 degrees.

This meant that inside the Four-Dimensional Barrier, the entire star system’s temperature was continuously rising.

Xiao Yu quickly figured out the reason.

“So that’s it… Because of the Four-Dimensional Barrier, this star’s heat can’t radiate outward, and it can only accumulate within the star system. Naturally, this leads to a continuous rise in temperature.”

After reaching this conclusion, Xiao Yu began to focus on another question: What was the rate of temperature increase? When would it rise to a level he could no longer withstand?

For this question, Xiao Yu quickly calculated the answer.

The conclusion was that the rate of temperature increase would accelerate. In fifteen years, regardless of distance from the star, the minimum temperature within the star system would reach over 3,000 degrees. Xiao Yu’s starships would have to consume increasing amounts of energy to resist the extreme heat.

The star system within the Four-Dimensional Barrier would become a literal steamer, and Xiao Yu’s starships would be like buns constantly steamed within it.

“In fifteen years, faced with the rising temperatures, I’ll deplete all my reserve energy and be forced to cannibalize other ships to use as fuel for the Elemental Decay Engine.”

“But even so, I won’t be able to hold out for long. The rising temperatures will only make energy consumption soar. By my calculations… after the temperature hits 3,000 degrees, I’ll have about five more years.”

“If I still can’t break through the Four-Dimensional Barrier by then, at the final moment, after dismantling all remaining ships, I’ll have no choice but to strip parts from the Hebei to acquire more fuel…”

“All things considered, I don’t have 150 years, not even 100 years. I only have 20 years… 20 years to find a way to break through the Four-Dimensional Barrier, or else I will die…”