Death's End

“Could Halo City really have achieved independence? Even Wade couldn’t be certain of that. Could the Federation Government and Fleet really have been scared of a few antimatter bullets? Maybe Halo City could have destroyed a few warships, or even a space city, but ultimately, Halo City would have been exterminated by the Federation Fleet. And in that version of history, there would be no Mercury base, no second chance.

“Even if Halo City had managed to achieve independence, continued to research curvature propulsion, discovered the slowing effects of the trails, and finally collaborated with the Federation Government to build more than a thousand lightspeed ships in time, do you think people would have agreed to build the black domain? Remember how confident people were that the Bunker World would survive a dark forest strike—why would they have agreed to isolate themselves in the black domain?”

AA’s words slid across Cheng Xin’s thoughts like drops of water across a lily pad, leaving no trace. Cheng Xin’s only thought was to find Yun Tianming and tell him everything. In her mind, a journey of 287 light-years would take a long time, but the ship’s AI informed her that the trip would only take fifty-two hours in the ship’s frame of reference. Everything felt unreal to Cheng Xin, as though she had already died and gone to another world.

Cheng Xin spent a long time gazing out of the portholes at space. She understood that each time a star leapt out of the blue cluster in front, swept past the ship, and joined the red cluster behind the ship, it meant that Halo had passed it. She counted the stars and watched as they turned from blue to red—the sight was hypnotic. Eventually, she fell asleep.

By the time Cheng Xin awakened, Halo was close to its destination. It turned 180 degrees and activated the curvature engine for deceleration—in fact, the ship was pushing against its own trail. As the ship decelerated, the blue and red clusters began to spread out like two clusters of exploding fireworks, and soon evolved into a sea of stars distributed evenly around the ship. The slowing down of the ship also gradually erased the red and blue shifts. Cheng Xin and AA saw that the Milky Way ahead of them still looked about the same, but behind them, none of the stars looked familiar. The Solar System was long gone.

“We’re now two hundred eighty-six point five light-years from the Solar System,” said the ship’s AI.

“So two hundred eighty-six years has already passed back there?” AA asked. She looked as if she had just awakened from a dream.

“Yes, if you are using their frame of reference.”

Cheng Xin sighed. For the Solar System in its current condition, was there a difference between 286 years and 2.86 million years? But she thought of something.

“When did the collapse into two dimensions stop?”

The question made AA speechless, as well. Right: When—if ever—did it stop? Was there an instruction within that small, packaged two-dimensional foil that would eventually stop it? Cheng Xin and AA had no theoretical understanding of how three-dimensional space collapsed into two dimensions, but they instinctively thought the idea of an instruction embedded into two-dimensional space to halt its infinite expansion was too magical, the kind of magic that seemed impossible.

Would the collapse never stop?

It was best to not think about it too much.

The star called DX3906 was about the Sun’s size. As Halo began decelerating, it still looked like an ordinary star, but by the time the curvature engine shut off, the star appeared as a disk whose light seemed redder than the Sun’s.

Halo engaged the fusion reactor, and the silence on the ship was broken. The humming of the engine filled the ship, and every surface vibrated slightly. The ship’s AI analyzed the data obtained by the monitoring system and confirmed the basic facts about this solar system: DX3906 had two planets, both of them solid. The one farther from the star was about the size of Mars, but it had no atmosphere and appeared gray in color—so Cheng Xin and AA decided to call it Planet Gray. The other planet, closer to the star, was about the size of the Earth, and its surface resembled the Earth’s: an atmosphere containing oxygen and many signs of life, but without evidence of agriculture or industry. Since it was blue, like the Earth, they decided to call it Planet Blue.

AA was very happy that her research had been confirmed. More than four hundred years ago, she had discovered the star’s planetary system. Before then, people had thought it was a bare star without any planets. Through that work, AA had gotten to know Cheng Xin. Without that coincidence, her life would have turned out completely differently. Fate was such an odd thing: Four centuries ago, when she had gazed at this distant world through the telescope, she could never have imagined that she’d come here one day.

“Were you able to see these two planets back then?” Cheng Xin asked.