Death's End

Cheng Xin and Guan Yifan embraced again. They cried tears of joy at the news concerning 艾 AA and Yun Tianming, and shared the happiness that they had enjoyed more than one hundred eighty thousand centuries ago. Their despairing hearts grew peaceful.

“I wonder what their life here was like?” Cheng Xin asked, tears glistening in her eyes.

“Anything was possible,” said Yifan.

“Did they have children?”

“Anything was possible. They could have even founded a civilization here.”

Cheng Xin knew that was indeed possible. But even if that civilization had lasted ten million years, the eight million-plus years that had come after would have erased all traces of it.

Time really was the cruelest force of all.

Something strange interrupted their meditation: a rectangle limned by faint lines of light, about a man’s height, hovered over the clearing like the dashed selection lines marked out by dragging a mouse. It moved through the air, but did not go far before returning to its original position. It was possible that it had been there all along, but the outline was so faint and thin that it was invisible during daytime. Whether it was made by a force field or actual substance, there was no doubt it was the creation of intelligence. The lines making up the rectangle seemed to evoke the line-shaped stars in the sky.

“Do you think this is the… gift they left for us?” Cheng Xin asked.

“Seems hard to believe. How could it have survived more than eighteen million years?”

But he was wrong. The object had indeed survived eighteen million years. And, if necessary, it could survive until the end of the universe, because it existed outside of time.

The door remembered that, initially, it had been placed next to the rock carved with text, and it had a real metal frame. But the metal had eroded away after only five hundred thousand years, though the object had always remained brand new. It had no fear of time because its own time had not yet started. It had been thirty meters underground, next to the carved rock, but it had detected the presence of humans and risen to the surface. During the process, it did not interact with the crust, moving like a ghost. It now confirmed that these two were indeed the ones it had been expecting.

“I think it looks like a door,” Cheng Xin said.

Yifan picked up a small branch and tossed it at the rectangle. The branch passed through it and landed on the other side. They saw a luminescent flock of little balloon creatures drift over. A few passed through the rectangle and one even crossed the glowing outline.

Yifan reached out and touched the frame. The light and his finger passed through each other, and he felt nothing. Without even thinking, he extended his hand into the space outlined by the rectangle. Cheng Xin screamed. Yifan pulled his hand back, and everything looked unharmed.

“Your hand…. It didn’t go through.” Cheng Xin pointed to the other side of the rectangle.

Yifan tried again. His hand and forearm disappeared as they entered the plane of the rectangle and did not go through. From the other side, Cheng Xin saw the cross section of his forearm, like the surface of a window. All his bones, muscles, and blood vessels were clearly visible. He pulled his hand back and tried again with a branch. It went through the frame without problems. Right after, two insects with spinning rotors passed through the rectangle as well.

“It really is a door—a smart door that recognizes what’s going through it,” Yifan said.

“It allowed you in.”

“Probably you, as well.”

Cheng Xin gingerly tried, and her arm also disappeared in the “door.” Yifan observed the cross section of her arm from the other side, and had a moment of déjà vu.

“Wait for me here,” Yifan said. “I’ll go investigate.”

“We should go together,” Cheng Xin said resolutely.

“No, you wait here.”

Cheng Xin grabbed him by both shoulders and turned him to face her. She looked into his eyes. “Do you really want us to also be separated by eighteen million years?”

Yifan stared back into her eyes for a long moment, and finally nodded. “Perhaps we should bring some things with us.”

Ten minutes later, they passed through the door, hand in hand.

Outside of Time Our Universe

Primordial darkness.

Cheng Xin and Guan Yifan were once again immersed in a time vacuum. The sensation was similar to when they had entered reduced lightspeed back in the shuttle. Time did not flow here, or maybe it was more accurate to say that time did not exist. They lost all sense of time, and experienced again that feeling of stepping across time, but existing outside of it.

Darkness disappeared; time began.

There is no appropriate expression in human language to express the moment at the start of time. To say that time began after they entered the door would be wrong because “after” required time. There was no time here, and thus no before or after. The time “after” they entered could have been shorter than a billion-billionth of a second, or longer than a billion billion years.