by Liu Cixin
Lin Yun and Ding Yi carefully drew the feeler back into the cabin. It’s a little like fishing, they thought. The string danced in the cabin. It was around one meter long, and looked like a shimmer of hot air on the summer blacktop, rendering the cabin wall behind it slightly wavy. Lin Yun reached out to it, but, like the helicopter pilot who paused before the first macro-electron, she stopped, then watched uncomfortably as Ding Yi passed his hand casually across the center of the string without affecting its dance in the slightest.
“No big deal. It doesn’t have any interaction with the physical matter of our world.” Then, after staring at the string with Lin Yun for a minute, Ding Yi let out a long sigh. “Frightening. A terror of the natural world.”
Lin Yun asked, “It can’t be excited like macro-electrons, so what’s so terrible about it? It looks like the most harmless thing in the world.”
Ding Yi sighed again, and then stepped away, seeming to leave behind the unspoken words, Just you wait.
* * *
It wasn’t long before the detection team at the base located another macro-nucleus three-hundred-odd kilometers away from the blimp. They continued on, and three hours later, in the sky over Hengshui, Hebei Province, captured their second macro-nucleus. Another three were located in quick succession, the farthest some four hundred kilometers away, the nearest just over one hundred. The problem was that the blimp was only equipped with two magnetic coils, each of which had a string stuck to it. Lin Yun suggested that they stick two to a single coil, and use the other coil to capture new strings.
“Are you crazy?” Ding Yi shouted sharply, startling Lin Yun and the pilot. He pointed at the two coils and their strings. “I’ll say it again: the coils must be kept at least five meters apart. Do you understand?”
Lin Yun looked at Ding Yi thoughtfully for a few seconds, and said, “There’s something you’re not telling me about macro-nuclei … for example, you’ve never been willing to explain what that last line on the gravestone means.”
“For something this important, I wanted to go directly to the higher-ups,” Ding Yi said, avoiding Lin Yun’s eyes.
“You don’t trust me?”
“That’s right. I don’t trust you.” Finding his resolve, Ding Yi looked straight at Lin Yun and said, “I can trust Colonel Xu and the others at the base, but I don’t trust you. The other person I don’t trust is myself. We’re actually quite alike. Both of us might use macro-nuclei without considering the consequences, albeit for different reasons. I would act out of a burning curiosity about the universe, but you—you would act out of an infatuation with weapons, driven by your failures.”
“Again with the weapons,” Lin Yun shook her head in confusion. “This pliable, infinitely thin string can pass through our bodies without us feeling anything, and it can’t be excited into a high-energy state. It’s got nothing to do with weapons.… Your refusal to explain is affecting our work.”
“With your training, you should be able to figure it out.”
“I don’t get it. Why is putting two of them together so frightening?”
“They’ll get tangled.”
“So what?”
“Think about what happens to two atomic nuclei that get tangled up in our world.”
Ding Yi knew he had peeled back the last layer of wrapping, and he watched her closely, hoping to see signs of shock and terror on her face. There were traces at first, but they were quickly replaced by excitement—the excitement of discovering a new toy.
“Fusion!”
Ding Yi nodded in silence.
“Would it release a lot of energy?”
“Of course. A ball lightning discharge is like a chemical reaction in the macro-world. Fusion would yield at least a hundred thousand times the energy of a chemical reaction of the same number of particles.”
“Macro-fusion—that’s what we’ll call it. Would its energy release have target selectivity like ball lightning?”
“In theory, yes, since they have identical energy release channels. They both experience quantum resonance with our world.”
Lin Yun turned back to look at the two hanging strings. “That’s brilliant. We used to require temperatures of a billion degrees for fusion, but now we can achieve it simply by tangling two strings!”
“It’s not that simple. The separation I’m insisting on is merely a cautionary measure. If you put those two strings together, they wouldn’t get tangled, since electrical repulsion would prevent them from coming into contact.” Ding Yi extended a hand to rub an incorporeal dancing string. “Combining strings requires a certain amount of relative speed to overcome that repulsion. You should now be able to understand the inscription from the gravestone.”
“Inciting F requires a speed of just 426.831 meters per second.… F is fusion?”
“That’s right. Two strings need to strike each other at that relative speed in order to become entangled. That’s fusion.”
Lin Yun’s engineering mind began working at top speed. “Since the strings carry a positive charge, it wouldn’t be hard to get each of them to two-hundred-some meters per second on two EM accelerator rails of sufficient length.”
“Don’t head off in that direction. Our primary task now is to think of a safe way to store them.”
“We should begin building two accelerators immediately—”
“I said, don’t go in that direction!”
“I’m just saying, we should make preparations. If we don’t, we won’t be ready when the higher-ups decide on macro-fusion tests…,” Lin Yun said. Then, suddenly she got angry, and paced urgently inside the narrow cabin. “What’s the matter with you? You’re so neurotic and shortsighted. It’s like you’re a different person compared to when you first came!”
Ding Yi gave a strange laugh. “Major, I’m just carrying out my pitiful little duty. Do you think I really care? I don’t. No physicist really cares about anything. Last century, when they turned over the formulas and techniques for atomic energy release to engineers and soldiers, then struck a pose of injured innocence at the price paid by Hiroshima and Nagasaki? Such hypocrites. They wanted to see the results, believe me. They wanted a demonstration of the power they had discovered. It was determined by their nature—by our natures. The only difference between them and me is that I’m not a hypocrite. I really want to see what will happen when those two strings of singularities get tangled together. Do I care about anything else? Hell no!”
Ding Yi had begun to pace as he spoke, and now the blimp rocked from their restless movement. The pilot turned back curiously to watch them fight.
“Then let’s go back and build rails,” Lin Yun murmured, her head down. She seemed momentarily drained of energy, as if something Ding Yi said had hurt her. And he soon found out the answer. On the flight back to base, sitting with him between the two dancing strings, Lin Yun said softly, “Do you really not care about anything apart from the mysteries of the universe?”
“Oh, I…,” Ding Yi stammered. “I just meant that I don’t care about the consequences of macro-fusion tests.”
THE SPECIAL LEADING GROUP
After the first successful capture of macro-nuclei, the base delivered a research report to the higher-ups that had the immediate effect of refocusing attention on the forgotten ball lightning weapons project.
Not long after, the base received a relocation order moving it from Beijing to a region in the northwest. The first things to move were the captured macro-nuclei, which by this point numbered twenty-five. Keeping them near the capital was highly dangerous, no question about it.
Relocating the base took a month. During that time, work on macro-nuclei capture (they referred to them as strings now) continued uninterrupted; by the time the move was complete, nearly three hundred strings had been captured and stored. Most of them were lightweight nuclei. It appeared that in the macro-universe, as in ours, lighter elements like hydrogen were most plentiful. But Ding Yi staunchly opposed defining them using terms like “macro
-hydrogen” and “macro-helium,” since it was now known that the elemental system of the macro-universe was completely different. It had an entirely unknown periodic table whose elements were not in one-to-one correspondence with our own.
The captured strings were stored in simple, hastily assembled warehouses in the Gobi Desert, stuck to magnetic coils in a grid separated by at least eight meters, and subject to an isolation field to guarantee that they were kept safely apart. From a distance, these warehouses resembled greenhouses, so, to the outside world, the base was the Research Center for Anti-Desertification Plants.
The higher-ups specifically named safety concerns as the reason for relocating the base, but its location clearly suggested another possibility.
This was the spot where China had detonated its first atomic bomb. Here, just next to the base, were remains of metal towers twisted by the atomic blast and a small, nearly forgotten commemorative plaque. A short journey would take you to the nuclear weapon proving ground: buildings and bridges constructed to observe the effects of the nuclear explosion on them, and a large number of old armored cars used as test targets. Geiger counters no longer clicked incessantly here—radiation left by the explosion had been drained by time—and it was said that a fair number of those abandoned objects had been carted off by local farmers for sale as scrap.
* * *
A major meeting to discuss the discovery of strings was held in Beijing. It was attended by senior leaders, including the premier. Lin Yun’s father chaired the meeting. The fact that he was able to take a full day away from vital war command to hold the meeting demonstrated the strings’ importance.
After listening to two hours of technical reports by Ding Yi and the other physicists who had just been added to string research, General Lin said, “These reports have been rigorous and comprehensive. Now I’d like to ask Professor Ding to clear up a few questions for us in the plainest language possible.”
Ding Yi said, “My understanding of the physical laws of the macro-world is still very superficial. Our study of strings has only just begun. For some questions, I’ll only be able to give a very vague or even uncertain answer. I hope that you all will understand.”
General Lin nodded. “First, when two strings from light atoms collide at critical velocity, how certain are we that they will undergo fusion? As far as I am aware, only two hydrogen isotopes and He-3 can cause a fusion reaction in our world.”
“Sir, it’s hard to compare the physical elements of the macro-world with ours. The unique string structure of macro-nuclei makes it relatively easy for them to combine, so fusion reactions between macro-atoms can be accomplished with much less effort than for our atoms. And macro-particles move at velocities a great many orders of magnitude slower than our particles. That means that, from the perspective of the macro-world, a collision speed of four-hundred-odd meters per second is equivalent to fusion temperature in our world. So we can be certain of producing fusion if we achieve a collision at that critical velocity.”
“Excellent. The next, and most important, question: What will the size and effect scope of fusion energy be?”
“Sir, this question involves many variables, so it’s difficult to be certain. This is the question that I’m most concerned with, too.”
“Can we try to come up with a relatively conservative estimate, like the equivalent of fifteen or twenty megatons of TNT?”
Ding Yi shook his head with a smile. “Definitely not that high, sir.”
“For safety’s sake, we’ll base our thinking on that, then. That is roughly the biggest thermonuclear yield that humanity has detonated. In the mid-twentieth century, during US ocean tests and Soviet land tests of that yield, the destructive radius was around fifty kilometers, well within controllable range. So what’s your worry?”
“Sir, I’m afraid you’re forgetting one thing: the high selectivity that macro-particle energy discharge has for its target. Conventional nuclear fusion releases its energy without any selectivity at all. It acts upon all matter in its surroundings—air, stone, earth, and so forth—which swiftly drains it away. So while conventional fusion may be high-yield, its area of effect is limited. But macro-fusion is different. The energy it releases acts on only one specific type of matter, and all other matter is completely transparent to it. If there’s only a very small amount of that matter type, the energy drain will be small, but the area of effect will be large indeed. I’ll give you an example: a twenty megaton release of energy without selectivity would turn the region within a fifty kilometer radius to cinders, but if that energy only acted upon hair, it would be enough to turn everyone in the world bald.”
It was an amusing example, but no one laughed. The climate of the meeting remained serious and oppressive.
“Are you now able to determine a string’s specific energy release target?”
“Yes. We discovered a while ago that microwaves are modulated into a complicated spectrum when passing through a macro-electron—different spectrums for different macro-electrons, as if they were fingerprints. Macro-electrons having the same discharge targets share a spectrum. Theoretically, this method will also apply to strings.”
“But obtaining the spectrum of a particular class of macro-electron at first required discharge tests. You now believe that strings that share a spectrum with macro-electrons will also share a discharge target. Is there a theoretical basis for this?”
“Yes. We are able to prove this.”
“So what are some of the targets of the three-hundred-odd strings you have captured?”
“All kinds. The most dangerous are those that target living organisms. Fusion of those strings would have unimaginable destructive power.”
“One final question: Are there strings that release into electronic chip targets?”
“As in the case of macro-electrons, these are very rare. At the moment, we have collected only three of them.”
“Good. Thank you.” General Lin concluded his questioning, and the meeting fell into silence.
“The situation, I think, has been fully explained,” said the premier, who had kept silent until this point. “Everyone not in the leading group is dismissed.”
* * *
A thousand kilometers away, the ball lightning research base was engaged in intense preparation for macro-fusion tests.
The string accelerator rails, each of them more than ten meters long, were complete. They resembled two model railroad bridges, and, indeed, their code names were “Bridge 1” and “Bridge 2.” The two strings would be accelerated to 250 meters per second on these bridges before colliding and undergoing macro-fusion.
The strings to be used in this experiment were those with the greatest practical significance: strings that released into electronic chips.
The bulk of the work went into setting up the target area. The base began importing huge quantities of electronic waste from overseas, most of it junked computer motherboards and network cards. Under the wartime economic blockade, e-waste was among the few products it was possible to import, and it was acquired in large quantities from third parties or even directly from the enemy. It was collected domestically as well. Ultimately, eighty thousand tons of e-waste were amassed and piled into unnatural mountains in the Gobi Desert. The boards and cards, bearing a huge number of chips, were arranged in three target circles around the central fusion point, the innermost at a radius of ten kilometers, and the outermost at one hundred kilometers, which included two small county towns on the edge of the Gobi. Small yellow surveying flags were used in this region, under each of which was anchored a black sealed bag holding several boards.
At the final work meeting, Ding Yi said, “I’ll warn you of one thing: since the energy density will be high in the vicinity of the point of macro-fusion, there will be no target selectivity. Everything within a radius of two hundred meters will be incinerated. That means the rails will be single-use, and test personnel must maintain a safe distance of at least two thousand meters from the
fusion point and ensure that they have no electronic equipment on their person.”
Everyone waited, but Ding Yi said nothing more. “Is that all?” Colonel Xu asked.
“I’ve said everything I need to say to the people I need to say it to,” he said, without emotion.
“Are you anticipating something unpredictable?” Lin Yun asked.
“As of this moment, I have not found anything predictable about macro-fusion.”
“It’s just two nuclei. They may be macro-nuclei, but it’s only two of them. In micro-fusion in our world, a hydrogen bomb with a mass far greater than those two strings has a yield of only a few megatons.”
Ding Yi said nothing, but just shook his head—whether to express his own lack of understanding or his helplessness at Lin Yun’s naïveté, it was hard to say.
The next day, a battalion of soldiers from a local garrison arrived to strengthen security at the base. This caused excitement, since it was a sign that the test was about to start.
“Even if the fusion energy only destroys chips in the first target circle, we will have acquired an unstoppable weapon. Think of it: How can a fleet defend against an explosion ten kilometers away? An explosion that cripples all of its electronics?” Lin Yun enthused.
Her mood was shared by everyone on base. Their first failure had robbed them of the chance to make history, but now a second chance was in front of them, and it was even more palpable.
Late that night, Lin Yun and a few engineers were still making final adjustments to the bridges. To avoid detection from the air, the two bridges had been set up in a large tent the size of a gymnasium. During the test, the tent would be the first thing destroyed by the fusion energy. Ding Yi called Lin Yun outside, and they walked in the cold Gobi wind.
