by Cixin Liu
*
On the transport plane back to base, Lin Yun squatted silently in a corner holding her helmet, her slender body curled up into a ball, looking alone and helpless like a girl lost in the wilderness in the dead of winter. Ding Yi felt a sudden compassion for her, so he went over and sat down next to her with words of comfort:
“You know, our success has been pretty great. Through macro-electrons, we can view the most profound mysteries of matter on a macro scale, something that was once only possible by entering the microscopic world. Compared to this achievement, the military use of ball lightning is insignificant—”
“Professor Ding, do people burned up by ball lightning remain in a quantum state?” Lin Yun interrupted him with a mindless question.
“Yes. Why?”
“You once said that the teacher would come to attack me.”
“That was just random nonsense. Besides, you didn’t believe me, did you?”
Lin Yun rested her chin on the helmet lying on her knees, and looked straight ahead. “After you mentioned it, I slept with a gun with the safety off. I really was afraid, but I was too embarrassed to let anyone know.”
“I’m sorry I frightened you.”
“Do you think it’s really possible?”
“Theoretically... perhaps. But the probability is so low that it’s not going to happen in the real world.”
“But it is possible,” Lin Yun murmured. “And if the teacher can attack me, then I can attack the enemy carrier.”
“What?”
“Professor Ding, I can take another fishing boat close to the enemy fleet.”
“...and do what?”
“Incinerate myself with ball lightning. Wouldn’t that turn me into a quantum soldier?”
“What are you talking about?”
“Think about it. In a quantum state, I can sneak into the carrier, and the enemy will have no way to find me, since the moment they notice me, my quantum state will collapse, just like you said. There’s a large arsenal on board, and thousands of tons of fuel. So as long as I can find those, I’ll be able to easily destroy the carrier.... Oh, and I can find Lieutenant Colonel Kang Ming and the other Dawnlight personnel. We could become a quantum unit...”
“This loss has turned you into a child, I see.”
“I never was very old.”
“You should go rest. We still have two hours until Beijing. Get some sleep.”
“Is what I described possible?” Lin Yun turned to look at Ding Yi, with a look of entreaty in her eyes.
“Okay. Let me tell you what a quantum state really is. In a quantum state, you—ah, supposing you’ve already been incinerated by ball lightning—you are just a probability cloud. In that cloud, everything you do is indeterminate. You lack the free will to decide where you will appear. Your position in the probability cloud, and whether you will be alive or dead when you appear, is indeterminate, decided only when God rolls his dice. If you are burned up on the fishing boat, then the probability cloud for quantum-you will be centered on that boat. In the surrounding space, you have a very small probability of appearing in the carrier’s arsenal or fuel storage. You will most likely appear in the water, and if you’re in a live state at that time, you will very quickly drown. Then your quantum state will no longer include the probability of being alive; you will be dead in every probability. Taking a huge step back, even if you hit the probability jackpot and appear in some critical part of the enemy carrier, will you be alive then? How long can you stay there? An hour, or a tenth of a second? Also, the moment one enemy, or one of the enemy’s cameras, catches sight of you, you will immediately collapse into that pile of ash in the center of the probability cloud to await your next jackpot. And when that opportunity comes, the carrier will be eighteen thousand kilometers away and there may no longer be any war left on Earth.... Finally, you’ve forgotten one point: those Dawnlight soldiers died from artillery shells, not ball lightning. Before their sacrifice, the ball lightning weapons were destroyed and sent to the bottom of the sea, so the soldiers did not turn quantum.... Lin Yun, you’re like the little match girl, seeing all kinds of illusions. You really need to rest.”
Lin Yun abruptly flung aside her helmet, then leaned against Ding Yi’s shoulder and started crying as if heartbroken. She cried sorrowfully, her slender frame trembling in Ding Yi’s embrace, as if letting out all of the anguish in her life at once....
*
“You can imagine how I felt at the time,” Ding Yi said. “I thought I was the sort of person for whom all emotions apart from rational thought were nonessential, and that impression has been reinforced on several prior occasions. But now I know that something else in addition to rationality can occupy a person’s entire mind.... Lin Yun seemed to have shrunk down. The old unshakable, goal-oriented major was now a fragile, helpless little girl. Was that who she really was?”
“Maybe a combination of the two. I understand women even less than you,” I said.
“Jiang Xingchen’s death already weighed heavy on her, then the failure of the mission smashed through the limit of what her psyche could endure.”
“That’s not a good state to be in. You should get in touch with her father.”
“Listen to yourself. How could I contact someone so high up?”
“I’ve got General Lin’s phone number. He gave it to me himself, and asked me to look after Lin Yun.”
I noticed that Ding Yi had not moved, and was staring at me. “It’s no use.”
His words frightened me. It was only then that I realized: Ding Yi’s story was cloaked in a shroud of sadness.
He stood up, walked to the window, and looked quietly out at the chilly night. It was a long while before he turned around again. He pointed at the empty bottle on the table. “Got another one?” I rummaged around for another bottle, opened it, and poured him half a glass. He sat down, looked squarely at the glass, and said, “There’s more. More than you ever would have imagined.”
* Only combatants wearing the uniform of their country enjoy the rights of captured soldiers under the Geneva Convention.
Strings
After their mortal failure in battle, ball lightning weapons research and deployment work came to a halt. Most personnel were transferred away, and even though the unit had not been disbanded, the base was a depressing place. It was then that Zhang Bin passed away.
*
“Zhang Bin was, after all, one of the pioneers of domestic ball lightning studies, so we decided to honor his wishes and conduct a ball lightning funeral. This would have to be kept confidential, and since you were an outsider then, we didn’t notify you,” Ding Yi explained.
I sighed softly. It was an unusual time, and my feelings were not overly stirred up by my advisor’s passing.
*
The funeral was conducted on the base at the lightning test ground. It was overgrown with weeds, so they cleared a patch in the center for Zhang Bin’s remains. When everyone had retreated to the one-hundred-meter safe line, a single excited high-energy ball of lightning flew from one corner of the test ground at slow speed. It floated slowly over Zhang Bin’s body, whistling that deep xun music, as if narrating the unfortunate life of this ordinary explorer. Ten minutes later, the ball disappeared with a bang, and white smoke rose from the body. The white sheet covering it collapsed; underneath, all that was left was fine bone ash.
Since work at the base had stopped, Ding Yi had returned to the Institute of Physics in the city to continue theoretical research on macro-electrons. He had missed Zhang Bin’s funeral, but he had seen the papers of calculations left behind in Zhang Bin’s effects and had been stunned by the sheer amount of work in them. In his eyes, Zhang Bin had not been granted the imagination or opportunity for theory, but had lived a life of wandering uncertainly through the muddy wilderness; he deserved respect as well as pity. Ding Yi felt he ought to visit the grave of that pioneer.
Zhang Bin’s grave was in a public cemetery near Badaling.
Lin Yun drove Ding Yi out there one afternoon. They followed the stony path to the cemetery that afternoon, a carpet of golden leaves under their feet, and a stretch of the Great Wall peeking out of the distant mountains blanketed in red. Another autumn had come, the season of dying, of parting, and of writing poetry. A shaft of light from the setting sun reached through a gap in the mountains to touch the lines of headstones.
Ding Yi and Lin Yun stood before Zhang Bin’s plain headstone, pondering their own thoughts until the sun had completely set.
Lin Yun murmured a Frost poem:
Two roads diverged in a yellow wood,
And sorry I could not travel both...
I took the one less traveled by,
And that has made all the difference.
Her voice was like a woodland spring.
“Have you ever thought of taking a different road?” Ding Yi asked.
“Is there one?” she said softly.
“Leave the army after the war, and come study macro-electrons with me. I’ve got the theory skills, and you’re an engineering genius. I’ll build the ideas, and you’ll be in charge of experiments. It’s very possible we’ll make the greatest breakthrough in modern physics.”
She smiled at him. “I grew up in the army. I don’t know if I could entirely belong anywhere else.” She hesitated before adding, “Or to anyone else.”
Ding Yi said nothing. He walked up to the gravestone and placed the fresh flowers he had brought on the pedestal. As he did so, something on the stone caught his attention, and for a long while, he didn’t straighten up. Eventually he squatted down and peered closely, his face practically pressed against the stone.
“My God. Who drafted the inscription?” he exclaimed.
His question caught Lin Yun by surprise, since at Zhang Bin’s request, nothing had been put on the stone but his name and his dates, since he felt that there was nothing worth saying about his life. Lin Yun came over for a closer look, and then froze in shock. In addition to the large inscription, the face of the marker was densely covered with small carved letters. Lettering was on the top and sides of the stone, too, along with formulas and calculations. It was as if the gravestone had been dipped in a liquid made of formulas.
“Oh, they’re fading. They’re disappearing!” Lin Yun shouted.
Ding Yi roughly pushed her away. “Turn around! With one less observer they’ll collapse more slowly.”
Lin Yun turned around and wrung her hands anxiously. Ding Yi leaned on the stone and began reading the text line by line. “What is it? Can you see anything?” she asked.
“Keep quiet!” he said loudly, still focused on reading.
Lin Yun rummaged in her pockets. “Should I go back to the car for a pencil and paper?”
“There’s no time. Don’t bother me!” he said, reading the text with astonishing speed. His eyes were locked fiercely on the stone, as if trying to pierce through it.
Now the last bit of light in the west painted the gravestones an eerie blue, and the surrounding woodland was immersed in a sea of darkness. The few gleaming stars that had emerged hung unblinkingly in the sky. From time to time there was the faint whisper of leaves rustling in the gentle breeze, which soon stopped, as if some unknown power was holding its breath. Stillness enveloped everything, like the whole world was focusing its attention along with Ding Yi on the quantum inscription.
Ten minutes later, Ding Yi had finished reading the front of the gravestone, and, after a quick scan of the top and sides, began reading the back. It was completely dark now, so he took out a lighter and read rapidly in the light of its weak flame.
“I’ll get a flashlight!” Lin Yun said, running off along the path between the ranks of gravestones to the car. When she returned with a flashlight in hand, the lighter flame had gone out. She found Ding Yi sitting with his back against the gravestone and his legs stretched out in front of him, looking at the stars.
On the gravestone, the inscription had vanished without a trace. The smooth marble surface reflected the flashlight beam like a mirror.
At the light from the flashlight, Ding Yi regained his senses like a man waking from a dream. He reached out, pulled Lin Yun around to the back of the gravestone, and pointed to its base. “Look at that. There’s one line left. It’s not in a quantum state, and it’s the only line of the inscription in Chinese.” Lin Yun crouched down and read the elegantly carved text:
Bin, inciting F requires a speed of just 426.831 meters per second. I’m very afraid.
“I know that handwriting!” Lin Yun said, staring at the words. On more than one occasion, she had read Zhang Bin’s notebook, its alternating pages burned by ball lightning.
“Yes. It’s Zheng Min.”
“What did she carve?”
“A mathematical model. A complete description of macro-atoms.”
Lin Yun sighed. “We really should have brought a digital camera.”
“It doesn’t matter. I’ve got it all in my head.”
“You do? All of it?”
“Most of it I’d derived already. But my theoretical system was stuck on a few points that she cleared up.”
“It must be a very important breakthrough!”
“Not just that. Lin Yun, we can find macro-nuclei!”
“The nuclei of macro-atoms?”
“Yes. By observing the movement of a macro-electron in space, we can use this model to precisely determine the exact location of the macro-atom it belongs to.”
“But how can we detect those macro-nuclei?”
“The same as with macro-electrons, and just as surprisingly simple: we can see them with the naked eye.”
“Wow... what do they look like? I remember you said that the shape of macro-nuclei would be completely different from the shape of macro-electrons.”
“Strings.”
“Strings?”
“Yes, strings. They look like a length of string.”
“How long? How thick?”
“They’re in basically the same class as macro-electrons. They’re about one to two meters long, depending on the atom. And they’re infinitely thin. Every point is a dimensionless singularity.”
“How can we see an infinitely thin string with the naked eye?”
“Because light bends in its vicinity.”
“So what does it look like?”
Ding Yi half closed his eyes, like someone who has just woken up attempting to recall a dream. “It’ll look like... a transparent crystalline snake. Or a hanging-proof rope.”
“That second one’s a strange analogy.”
“That’s because the string is the smallest building block of macro-matter. It’s impossible for it to be cut.”
On the way back, Lin Yun said to Ding Yi, “One more question: You’re the cutting edge of theoretical physics in this country. It’s hard to believe that decades ago, another ball lightning researcher was as well. There’s certainly an element of subjectivity in Zhang Bin’s assessment of his wife, but was Zheng Min really capable of making those discoveries?”
“If humanity lived in a frictionless world, Newton’s Three Laws might have been discovered even earlier by someone even more ordinary. When you yourself become a macro-particle in a quantum state, you might have a far easier time understanding that world than we do.”
*
And so the base started working on collecting macro-atomic nuclei.
They began by using the bubble optical detection system to make precise observations of the free-motion state of macro-electrons in the air, understanding now that the complicated floating path followed by a macro-electron, or the ball lightning that resulted when it was excited, was in fact an endless succession of atomic electron transitions—quantum leaps—that appear to us like continuous motion. If that macro-electron did indeed belong to a macro-atom, the magnificent mathematical model that had appeared on Zhang Bin’s gravestone could determine the position of a macro-atom’s nucleus through a complicated calculation involvi
ng various parameters of the atomic transition.
The first set of ten free-moving macro-electrons observed were discovered at a height of five hundred meters. A macro-electron had to be observed continuously for half an hour to obtain enough raw data for the calculation. The results showed that, of those ten macro-electrons, two were free electrons, and the other eight each belonged to a different macro-atomic nucleus, between three hundred and six hundred kilometers away. This was very close to Ding Yi’s initial estimate of the size of macro-electrons. Three of the nuclei were beyond the atmosphere in space, one was deep in the Earth’s crust, and of the four in the atmosphere, two were outside the country. So the researchers set off in search of one of the in-country macro-atomic nuclei, which was 534 kilometers away from the observed macro-electron.
It was wartime, so it was impossible to requisition a helicopter, but fortunately the base had three helium blimps they had used for capturing macro-electrons. These were easy to use, and cheap to fly; their one flaw was that they moved very slowly, at maximum speed no better than a car on an expressway.
Skies were blue in northern China that day, an excellent time for capture. They flew westward for more than four hours, crossing the Shanxi border. Below them was the unbroken line of the Taihang Mountains. The position of macro-nuclei was relatively constant compared to macro-electrons, but they still moved slowly, meaning the base had to continuously monitor the macro-electron and notify the capture blimp of the latest calculations of the macro-nucleus position. After the observation team on base notified the blimp that it had reached the target’s location, the aviators turned on the blimp’s optical detection system, whose pattern recognition software had been modified to detect a length of string rather than a round shape. There was a roughly one-hundred-meter margin of error for locating the macro-nucleus, so the optical detection system carried out fine observations of that area of sky to quickly locate the target.
