The Question Tree

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In early spring, they tie vibrantly colored ribbons to the branches of the tree. Most of them mark their ribbons–with some private symbol, or a name, or even a whole question. Sometimes a ribbon is left bare, and they count on remembering where they placed it. Or they don’t intend to check.
The girls mostly come together, in small groups, laughing and taking their time picking the best spots. Which spots are "best" is the subject of constant and passionate debate.
The boys mostly come alone, later in the evenings, and for them the goal is height. "Higher branches, better chances," one of them responded when I queried him. He had no deeper reasoning to offer.</em>
"Never mind that," Tanya said. I turned away from my terminal to look at her. "I am doing a much more important project."
"What would that be?" I asked.
"I am teaching quantum mechanics to Bruno."
I laughed. "Isn't this a little early? He's only nine."
She waved a hand, dismissing my objection. "I was younger when I started. Besides, nine is old for a dog."
"Oh yes, that little fact. That might also be a problem."
Bruno sauntered over to me. I gave him a scratch behind the ears.
"I don’t know if any dog could really understand QM," I said.
Tanya scoffed. "Is that different from any human?"
"Fair point," I said, returning to my report.
<em>Each spring the Question Tree blooms once. During the rest of the year it is an unremarkable plant, a common member of a species that makes up much of the deciduous forest surrounding the village. But during its week-long bloom, the Question Tree reveals an extraordinary phenotype. It flowers in two colors, in almost perfect balance: blue and white in seemingly random variation.
The blue flowers actually have a slight edge, comprising about 52% of the total each year. Still, the concurrence of two colors on the same tree is exceptional. There are millions of the Question Tree's species in the forest, and it alone blooms dichromatically. Consequently, its year-to-year variation provides a metric for validating the simulation's RAN5 algorithm—</em>
"Richard, what are you obsessing over? Watch our lesson. Bruno, come here."
I spun around again. Bruno trotted back to Tanya, an eager pupil.
"Okay, Bruno, observe this particle."
Tanya held out a dog biscuit. Bruno stared at it intensely.
"See, Bruno, you have observed its position. Now, if you observe again in the same way..."
Tanya closed her hand briefly, then opened it.
"...the position is the same. The wavefunction has collapsed. You may record this measurement."
She gave Bruno his treat. He crunched it happily as Tanya continued.
"Now, let us consider a system where position is unknown."
Tanya held out both her hands, both closed.
"What must we do?"
Bruno considered for a moment, then lifted a paw to Tanya's left hand. She opened it. Empty.
"Correct!" she said, "We make another observation, and detect nothing. But the particle must be somewhere, and so there is only one possibility left. The wavefunction has collapsed again."
She opened her right hand, revealing another biscuit.
"We can again record our measurement," she said, and tossed him the treat.
I clapped. "Excellent lesson. He’s learning quickly."
"Yes, we’ve worked hard," Tanya said, walking over. She sat down and glanced at the terminal. "What have you been playing at, while we worked? Torturing your little subjects?"
"Let's not argue," I said. "The simulants don't suffer any more than real beings do, and the development—"
“—of sapient species is a non-trivial feature of the universal life cycle - I've read your Ethics statement. It's cruel. But okay, no argument."
We sat silently for a while and I let the simulation run. The years passed in rapid succession. The Question Tree bloomed and withered, bloomed and withered.
"What’s that?" Tanya asked, noticing it on the terminal. I paused the simulation.
"An anomaly I'm using to track some parameters. It's a tree with two colors of flower, which appear in a different pattern every year. It’s unlike any other of its kind. Some simulants have developed rituals around it. They call it the Question Tree."
Bruno was rubbing against Tanya's leg, hoping for another lesson. She lifted him onto her lap. “Well? Why?"
"The flowers. They tie ribbons to the tree’s branches before it blooms - the ribbons represent questions they're asking. They tie them on and then check which color flower bloomed nearest their ribbon, and that’s their answer. There are only two possibilities: yes or no. A blue flower or a white one."
I displayed a single flower. It was white, and a purple ribbon was tied beside it.
"What was the question for this one?" Tanya asked.
"I don't know," I said. "Purple usually means a romantic question. Probably a boy from the village, asking if his sweetheart cares for him." I chuckled. "He’ll be disappointed. White means no."
Tanya frowned. "Has he seen it yet?"
"Unlikely," I said, checking the timecode. "Why?"
"Change it for him."
"What? No. I can't do that."
"Why not? Don't give me any nonsense about your algorithms. It won't affect anything."
I pointed at Bruno. "Have you forgotten his lesson? I've seen it. I can't change it now."
Tanya scoffed. "Nobody has seen it. You don't count. You're not in the simulation."
I hesitated.
"Oh, come on," Tanya said, "Give them a little joy for once. It won’t ruin the study."
With a sigh, I gave in, and entered a command. "Done," I said, "just for you."
I switched off the terminal and turned to Bruno.
"Now, I want to teach a lesson," I said. I grabbed a biscuit and held out my hands, palms closed.
Bruno pawed at the left. I opened it, and tossed him his well-observed treat.
"He’s a genius," Tanya said.
I stared at my left hand.
"Funny," I said, "I could have sworn it was in my right."
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