The Three-Body Problem

“I’m Aristotle. You changed your ID, but we all recognize you. In the previous two civilizations, you traveled to the East.” The speaker was the man with the Greek chiton. He had a head of white curls.

“Yes.” Wang nodded. “There, I witnessed the destruction of two civilizations, one by extreme cold, another by a blazing sun. I also saw the great efforts the scholars of the East expended in trying to master the laws governing the sun’s motion.”

“Ha!” The sound came from a man with a goatee that curled upward. He was even thinner than the pope. “Eastern scholars tried to understand the secrets of the sun’s motion through meditation, epiphany, or even dreams. Utterly laughable!”

“This is Galileo,” said Aristotle. “He advocates understanding the world through observation and experiment. He is an unimaginative thinker, but his results demand our attention.”

“Mozi also conducted experiments and observation,” Wang said.

Galileo snorted. “Mozi’s way of thinking was still Eastern. He was nothing more than a mystic dressed as a scientist. He never took his own observation data seriously, and he constructed his model based on subjective speculation. Ridiculous! I feel sorry for his refined equipment. We’re different. Based on large amounts of observational data and experiments, we make strict, logical deductions to build a model of the universe. Then we go back to experimentation and observation to test it.”

“That’s correct.” Wang nodded. “That’s also my way of thinking.”

“Have you brought a calendar as well, then?” The pope’s tone was mocking.

“I don’t have a calendar. I only brought a model built upon observation data. But I must make it clear that even if the model is correct, it’s not certain that by using it one can master the precise details of the sun’s motion and create a calendar. However, it’s a necessary step.”

A few lonely claps echoed throughout the Great Hall. The applause came from Galileo. “Excellent, Copernicus, excellent. Your pragmatic way of thinking, adapted to the experimental, scientific approach, is lacking in most scholars. Based on this alone, your theory is worth listening to.”

The pope nodded at Wang. “Go ahead.”

After calming himself and walking to the other end of the long table, Wang said, “It’s actually pretty simple. The reason why the sun’s motion seems patternless is because our world has three suns. Under the influence of their mutually perturbing gravitational attraction, their movements are unpredictable—the three-body problem. When our planet revolves around one of the suns in a stable orbit, that’s a Stable Era. When one or more of the other suns move within a certain distance, their gravitational pull will snatch the planet away from the sun it’s orbiting, causing it to wander unstably through the gravitational fields of the three suns. That’s a Chaotic Era. After an uncertain amount of time, our planet is once again pulled into a temporary orbit and another Stable Era begins. This is a football game at the scale of the universe. The players are the three suns, and our planet is the football.”

A few hollow laughs rang out in the Great Hall. “Burn him to death,” the pope said impassively. The two soldiers standing at the door in rusty armor started toward Wang like two clumsy robots.

“Burn him.” Galileo sighed. “I had hopes for you, but you’re nothing more than another mystic or warlock.”

“Such men are a public nuisance,” Aristotle agreed.

“At least let me finish!” Wang shoved away the iron gauntlets of the two soldiers.

“Have you seen three suns? Or know anyone who has?” Galileo asked.

“Everyone has seen them.”

“Then, other than the sun that appears during Chaotic Eras and Stable Eras, where are the other two?”

“The sun that we see at different times may not be the same: It’s only one of the three suns. When the other two are far away, they look like flying stars.”

“You lack basic scientific training,” Galileo said, shaking his head. “The sun must move continuously to a distant spot. It cannot jump over the intervening space. According to your hypothesis, there should be another observable situation: The sun must get smaller than it usually appears but bigger than a flying star, and gradually shrink into a flying star as it moves farther away. But we’ve never seen the sun behave that way.”

“Since you have scientific training, you ought to have some knowledge of the sun’s structure.”

“That’s my proudest discovery. The sun is made of a sparse but expansive gaseous outer layer and a dense and hot inner core.”