“Thanks for sharing that, Lyle,” said Dana. She addressed the rest of the group. “Does anyone want to say anything in response?”
This was an opportunity, but Nat wasn’t going to jump in right away. It’d be best if the other group members spoke first.
Kevin started. “Sorry about my earlier remark. I didn’t mean that you were dumb for trying it. What I was thinking was it sounded like something I would do, and because of that, I had a bad feeling about how it was going to turn out. I’m sorry it didn’t work out better for you.”
“Thanks, Kevin.”
“And really, it’s not a bad idea. The two of you have got to be compatible if your paraselves are a couple.”
“I agree with Kevin that the two of you are compatible,” said Zareenah. “But the mistake that all of us keep making is that, when we see our paraselves experiencing good fortune, we think we’re entitled to the same good fortune.”
“I don’t think I’m entitled to Becca,” said Lyle. “But she’s looking for someone, just like I am. If we’re compatible, shouldn’t that count for something? I know I made a bad first impression, but I feel like our compatibility should be a reason for her to overlook that.”
“It’d be nice if she did, but she’s under no obligation to do that.”
“Yeah,” said Lyle grudgingly. “I see what you’re saying. I just feel so…I know I say this all the time, but I feel envious. Why am I like this?”
Now seemed like a good time. Nat said, “Something happened to me recently that I think might be similar to what Lyle’s going through?”
“Go ahead,” said Dana.
“Okay, I’ve got this hobby where I make jewelry, mostly earrings. I have a little online store where people can buy them; I don’t fill the orders myself, I just upload the designs and this company fabs them and mails them to customers.” That part was all true, which was good in case anyone wanted to look at her store. “My paraself was just telling me that some influencer happened across one of our designs, and posted about how she loved them, and in the last week my paraself has sold hundreds of earrings. She actually saw someone at a coffee shop who was wearing the earrings.
“The thing is, the design that got all the attention wasn’t one she made after I activated the prism; it’s one from before. Those exact same earrings are for sale in my store in this branch, but no one’s buying them here. She’s making money for something we did before our branches diverged, but I’m not. And I resented her for it. Why is she so lucky and I’m not?” Nat saw some others nodding in sympathy.
“And I realized, this didn’t feel the same as when I see other people sell a lot of jewelry in their online stores. This is different.” She turned to face Lyle. “I don’t think I’m an envious person by nature, and I don’t think you are, either. We’re not always wanting what other people have. But with a prism, it’s not other people, it’s you. So how can you not feel like you deserve what they have? It’s natural. The problem isn’t with you, it’s with the prism.”
“Thanks, Nat. I appreciate that.”
“You’re welcome.”
Progress. That was definitely progress.
Set up a rack of billiard balls and execute a flawless break. Imagine the table has no pockets and is frictionless, so the balls just keep rebounding, never coming to a stop; how accurately can you predict the path of any given ball as it collides against the others? In 1978, the physicist Michael Berry calculated that you could predict only nine collisions before you would need to account for the gravitational effect of a person standing in the room. If your initial measurement of a ball’s position is off by even a nanometer, your prediction becomes useless within a matter of seconds.
The collisions between air molecules are similarly contingent and can be affected by the gravitational effect of a single atom a meter away. So even though the interior of a prism is shielded from the external environment, the result of the quantum measurement that takes place when the prism is activated can still exert an effect on the outside world, determining whether two oxygen molecules collide or whether they drift past each other. Without anyone intending it, the activation of the prism inevitably gives rise to a difference between the two branches generated. The difference is imperceptible at first, a discrepancy at the level of the thermal motion of molecules, but when air is turbulent, it takes roughly a minute for a perturbation at the microscopic level to become macroscopic, affecting eddies one centimeter in diameter.
For small-scale atmospheric phenomena, the effects of perturbations double in size every couple of hours. In terms of prediction, that means that an error one meter wide in your initial measurements of the atmosphere will lead to an error a kilometer wide in your prediction of the weather on the following day. At larger scales, the propagation of errors slows down due to factors like topography and the stratification of the atmosphere, but it doesn’t stop; eventually errors on the kilometer scale become errors hundreds or thousands of kilometers in size. Even if your initial measurements were so detailed that they included data about every cubic meter of the Earth’s atmosphere, your prediction of the future weather would cease to be useful within a month’s time. Increasing the resolution of the initial measurements has a limited benefit; because errors propagate so rapidly at the small scale, starting with data about every cubic centimeter of the atmosphere would prolong the accuracy of the prediction by only a matter of hours.
The growth of errors in weather prediction is identical to the divergence between the weather in the branches on opposite sides of a prism. The initial perturbation is the difference in the collision of oxygen molecules when the prism is activated, and within a month, the weather around the globe is different. Silitonga confirmed this when he and his parallel self exchanged weather reports one month after activating a prism. The weather reports were all seasonally appropriate—there was no location that experienced winter in one branch and summer in the other—but beyond that they were essentially uncorrelated. Without anyone making an effort, the two branches had diverged visibly on a worldwide scale.
After Silitonga published these results, in a paper titled “Studying Atmospheric Upscale Error Propagation with the Plaga Interworld-Signaling Mechanism,” historians engaged in heated debates over the extent to which weather could affect the course of history. Skeptics acknowledged that it could affect individuals’ daily lives in various ways, but how often were the outcomes of history-making events decided by the weather? Silitonga didn’t participate in the debates; he was waiting for his other, yearlong prism experiment to conclude.
There were times when the clients came in just the right order, and Wednesday afternoons were like that for Dana. The afternoon began with one of her most demanding clients, a man who asked her to make all his decisions for him, whined when she wouldn’t, and blamed her whenever he eventually did take an action. So it was a relief to see Jorge immediately afterward, a breath of fresh air to clear out her office. The issues he was dealing with weren’t the most interesting she’d ever seen, but she liked having him as a client. Jorge was funny and kind, and always well-intentioned; he was tentative about the therapeutic process, but they’d been making steady progress on his poor self-image and the negative attitudes that were holding him back.
Four weeks ago there had been an incident. Jorge’s manager at work was a mean-spirited tyrant who belittled everyone who worked for him; one of the ongoing themes of Dana’s sessions with Jorge was helping him to ignore his manager’s insults. One day, Jorge had lost his temper and punctured all four tires of his manager’s car when he was alone in the parking lot. Enough time had passed that it seemed like there was no risk of him getting caught, and while part of him wanted to pretend that it had never happened, part of him still felt terrible about what he’d done.