Cixin Liu - Death's End

From Sophon’s gaze, Cheng Xin finally understood why she had been kept alive.

As the gravitational wave broadcast system had been destroyed and the sun’s ability to amplify radio waves had been suppressed, a living Cheng Xin posed no threat. On the other hand, in the unlikely event that humans still possessed some other method of broadcasting to the universe unknown to Trisolaris, eliminating the Swordholder might cause others to activate the broadcast. As long as the Swordholder was alive, however, the probability of that happening was virtually nil: Others would have a reason and excuse to shirk their responsibility.

Instead of the deterrer, Cheng Xin had been turned into a safety shield. The enemy had seen through her completely.

She was a fairy tale.

“Don’t celebrate too early,” AA said to Sophon, having recovered some of her courage. “We still have the spaceship Gravity .”

Sophon returned the katana to its sheath on her back in a single, smooth motion. “Foolish girl, Gravity has been destroyed. It happened an hour ago, when the handover occurred a light-year away. I regret that I can’t show you the wreckage because the sophons are in a blind zone.”

The Trisolarans had been planning and preparing for this moment for a long time. The exact time for the handover had been determined five months ago, before the sophons accompanying Gravity had entered the blind zone. The two droplets with Gravity had already received the order to destroy the ship at the moment of the handover.

“I’m leaving,” said Sophon. “Please convey to Dr. Luo Ji the deepest respect of all of Trisolaris. He was a powerful deterrer, a great warrior. Oh, and if you get the chance, also give Mr. Thomas Wade our regrets.”

Cheng Xin looked up, surprised.

“In our personality studies, your degree of deterrence hovered around ten percent, like a worm wriggling on the ground. Luo Ji’s degree of deterrence was always around ninety percent, like a fearsome cobra poised to strike. But Wade—” Sophon gazed at the setting sun behind the smoke, only a sliver of which now was above ground. Terror glinted from her eyes. She shook her head vigorously, as though trying to chase away a mirage in her mind. “He had no curve at all. No matter what the other environmental parameters were, his degree of deterrence stayed at one hundred percent! What a devil! If he had become the Swordholder, none of this would have been possible. This peace would have had to last. We’ve already waited sixty-two years, but we’d have had to keep on waiting, maybe for fifty more years, or even longer. And then Trisolaris would face an Earth equal to us in technology and power. We’d have to compromise…. However, we knew that humanity would choose you.”

Sophon walked away, taking large strides. She paused some distance away and turned around, calling out to the silent Cheng Xin and AA. “Get ready to go to Australia, you pitiful bugs.”

On the thirty-eighth day after the end of deterrence, the Ringier-Fitzroy observation station at the outer rim of the asteroid belt discovered 415 new trails in the interstellar dust cloud near the Trisolaran star system. Apparently, Trisolaris had sent a second fleet toward the Solar System.

This second fleet had left Trisolaris five years ago, and passed through the dust cloud four years ago. This had been a huge risk on Trisolaris’s part—if they couldn’t destroy humanity’s dark forest deterrence system within five years, the discovery of this fleet might have led to the activation of the deterrence broadcast. This meant that as long ago as five years, Trisolaris already had sensed the shifting mood toward dark forest deterrence among humanity and correctly predicted the kind of second Swordholder that would be elected.

History seemed to have been reset; a new cycle had begun.

The end of deterrence once again cast the future of humankind into darkness, but, just like in the first crisis over two centuries earlier, people did not connect this darkness with their individual fates. Based on analysis of the trails, the Second Trisolaran Fleet’s velocity wasn’t so different from that of the First Trisolaran Fleet. Even if they could accelerate more, the fleet wouldn’t arrive at the Solar System for at least two or three centuries. Everyone alive would be able to live out the remainder of their lives in peace. After the lessons taught by the Great Ravine, modern men and women would never again sacrifice the present for the future.

But this time, humanity wasn’t so fortunate.

Three days after the Second Trisolaran Fleet left the interstellar cloud, the observation system detected 415 trails in the second interstellar cloud. These trails couldn’t belong to a different fleet. The First Trisolaran Fleet had taken five years to go from the first dust cloud to the second, while the Second Trisolaran Fleet had taken only six days.

The Trisolarans had achieved lightspeed.

Analysis of the trails in the second interstellar dust cloud confirmed that they continued to extend through the cloud at lightspeed. At such high velocities, the trails left by the ships’ impacts became particularly prominent.

Timing wise, it appeared that the fleet had entered lightspeed as soon as it exited the first dust cloud; there didn’t appear to be a stage during which it accelerated.

If that was true, then the Second Trisolaran Fleet should have already or almost reached the Solar System. Using midsized telescopes, it was possible to see a patch of 415 bright lights about six thousand AU from the Earth. These were the lights generated by deceleration. Apparently the ships’ propulsion systems were conventional. The fleet’s velocity was now only 15 percent of the speed of light. This was evidently the fastest speed that still permitted safe deceleration before arriving at the Solar System. Based on the observed velocity and deceleration, the Second Trisolaran Fleet would arrive at the edge of the Solar System in one year.

This was a bit puzzling. It appeared as if the Trisolar ships were capable of entering and dropping out of lightspeed within an extremely short period of time, but they chose not to do so too close to the Trisolaran star system or the Solar System. After the fleet had left Trisolaris, the ships accelerated under conventional power for an entire year, until they were about six thousand AU from home, before entering lightspeed. Similarly, they dropped out of lightspeed at the same distance from the Solar System and switched to conventional deceleration. This distance could be covered in a month at lightspeed, but the fleet chose to spend a year traversing it. The cruise of the Second Trisolaran Fleet would thus take two years longer than it would if the entire voyage were conducted at lightspeed.

Only one explanation for this curious decision came to mind: It was motivated by a desire not to harm either solar system during the process of entering and dropping out of lightspeed. The safe radius appeared to be two hundred times the distance from the Sun to Neptune. This suggested that the power generated by the drives was two orders of magnitude greater than a star, which seemed unimaginable.

Exactly when the rate of Trisolaran technological progress had shifted from constant to explosive was a mystery. Some scholars believed that the acceleration began before the Crisis Era; others believed that the forward leap didn’t happen until the Deterrence Era. There was, however, general consensus on the causes for the technology explosion.

First, Earth civilization had a tremendous impact on Trisolaran civilization—on this point, at least, the Trisolarans likely didn’t lie. Since the arrival of the first sophon, the massive inflow of human culture profoundly changed Trisolaris, and some human values resonated with the Trisolarans. Trisolaran society broke down the barriers to scientific progress imposed by the extreme totalitarian political system that had been adopted as a reaction to the chaotic eras, encouraged freedom of thought, and began to respect the individual. These changes might have triggered ideological transformation movements akin to the Renaissance in that distant world, leading to leaps in scientific and technological progress. This must have been a glorious period in Trisolaran history, but the specific details were unknown.