Next they’ll ask us to lift the sophon block and teach science and technology across the board.

“This is important to you as well. The technology of Trisolaris has developed at a constant speed, and two centuries later, you still haven’t sent a faster follow-up fleet. In order to rescue the diverted Trisolaran Fleet, you have to rely on the future of humanity.”

I must go. Are you really able to go back on your own? The survival of two civilizations hinges on your life.

“No problem. I feel much better now. After I go back, I’ll immediately hand over the cradle system, and then I’ll have no more to do with all of this. Finally, I’d like to say thank you.”

Why?

“Because you let me live. Or, if you think about it a different way: You let us both live.”

The sphere vanished, returning to its eleven-dimensional microscopic state. A corner of the sun was peeking out in the east, casting gold across a world that had survived destruction.

Luo Ji slowly stood up. After taking a last look at the gravestones of Ye Wenjie and Yang Dong, he stumbled slowly back the way he came.

The ant had reached the summit of the headstone and proudly waved its feelers at the rising sun. Out of all life on Earth, it was the only witness to what had just taken place.

Five Years Later

Five Years Later

Luo Ji and his family could see the gravitational-wave antenna in the distance, but it was still another half-hour drive away. Only when they arrived did they get a real sense of its enormous size. The antenna, a horizontal cylinder a kilometer and a half long and fifty meters in diameter, was entirely suspended about two meters off the ground. Its surface was mirror-smooth, half of it reflecting the sky and half the northern China plain. It reminded people of a few things: the giant pendulums of the Three Body world, the sophons’ lower-dimensional unfoldings, and the droplet. The mirrored object reflected a Trisolaran concept that humanity was still trying to figure out. In the words of a well-known Trisolaran saying, “Hiding the self through a faithful mapping of the universe is the only path into eternity.”