Tristan got to the bottom of his champagne glass pretty quickly. He still had a haunted look about him, as if he’d seen a ghost in Central Park. Not really the champagne type, he raised one hand and hailed the Smart-ass Oboist.
“What can I get you?” Julie asked.
“The usual,” he said, his attention already on the dinner menu.
She faltered, her face pinkening slightly. “I’m sorry,” she said. “I feel like I should know what that is, but the memory escapes me . . .”
“Old Tearsheet Best Bitter!” he said, glancing up.
She frowned. “I don’t think we have that,” she said. “Is it an import?”
He gave her an Eagle Scout smile, but his tone was firm. “You know. I’ve been ordering it since this place opened. You definitely carry it.”
“All right,” she said with a skeptical smile, writing. “T-e-a-r-s-h-e-e-t? Bitter?”
“That’s right,” said Tristan.
We all perused the menu, until she returned a moment later with the announcement that they did not carry—and had never carried—Old Tearsheet Best Bitter. Tristan half stood up and looked incredulously over at the barman, who shrugged broadly, indicating he had never heard of that ale. That ale he’d been pouring Tristan for years.
Erszebet tugged at Tristan’s sleeve, pulling him back down into his seat. “This is the Diachronic Shear,” she said quietly. “There is no Tearsheet Brewery. After September of 1601, there never was.”
“That’s almost as big a tragedy as losing Les Holgate,” Tristan muttered under his breath.
IT WAS ODDLY intimate yet oddly formal, the six of us sitting around a proper dining table that was not littered with coffee cups, whiteboard markers, handheld devices, and notepads. That we were holding actual silverware, and napkins larger than a coaster. That we allowed a stranger to approach us and do something exquisitely mundane: serve us a meal that was not delivered in to-go containers or rewarmed in a microwave. That we ate slowly, savoring our food and relaxing in the hum of conversation around us, and feeling a part of the human race—or at least, that fraction of the human race that frequented the Apostolic Café.
As we ate, we reviewed our lessons learned about the use of time travel, all of which Erszebet felt the need to point out she was already aware of.
“Very well,” said Tristan, setting down his fork. “If you know everything, save us the time and aggravation and tell us what we don’t know yet.”
She made a tch’ing sound and shook her head. It is fair to say her condescension toward him was softening now—a little—into something more resembling big-sister exasperation. “What you do not know is almost everything. Quite literally. Except what my számológép could anticipate on any given Strand.”
“Clearly we’re still in the learning process there,” said Tristan. “We need to think in a little more depth about how to master the Strands.”
“You cannot master the Strands,” said Erszebet. “It is like a doctor with medicine. You can only practice. And you cannot do even that without the számológép.”
“It does seem to me there are discernible algorithms regarding the Strands,” said Frank Oda. He touched his wife’s wrist gently and she reached down to the floor for a bookbag, which she raised and handed to him.
“There is always, what is the term, wiggling room,” corrected Erszebet.
“It is a complexity theory problem—a branch of what mathematicians call graph theory,” said the professor.
“Graph? As in graph paper?” I asked.
“Math geeks use the term differently,” Oda said, “to mean structures of nodes connected by branches. Like a számológép, or Gráinne’s broom, or Rebecca’s heirloom.”
“Or the many forking Strands of history,” Rebecca said.
“Point being, a lot of progress has been made in recent decades around just these sorts of problems,” Oda said. Anticipating an objection from Erszebet, he added, “Which isn’t to say there’s no more ‘wiggling room,’ but we can tackle these questions now with well-tested algorithms, and graphical UIs.” He opened his bag and reached inside.
“We are better than any other humans at extrapolating from what the Strands tell us.”
“That’s true,” said Oda. From the bookbag, he withdrew an iPad. Rebecca took the bag from his lap and returned it to the floor as he set the iPad on the table before him. “However, computers can enhance and sharpen the abilities you already have. With all respect, even witches can benefit from an app.”
Erszebet looked at the iPad. “What is this?”
“It’s a present,” said Frank Oda. “I would not insult your history with the missing számológép by calling this a replacement számológép, so let us say it is your quipu.”
“That is a computer,” she argued. “It is a piece of machinery. It does not even have moving parts.”
Oda smiled at her, undisturbed by her attitude. “I took the premise of the quipu, and what you had shown me of your számológép, and I designed a program to do algorithmically what you do intuitively. Plus a graphical user interface to go with it!” He held up the iPad so that everyone could see it. On the screen was a branching diagram that might best be described as a mathematician’s attempt to reproduce the structure of those devices used by the witches. Call it a quipu, a broom, or a számológép if you will; they all had the same many-branched structure, and so did the thing that Oda-sensei had rendered on this screen. It was a constellation of small gleaming figures in various shapes and colors, like a Christmas tree; the structure that held it together was a snarl of fine colored lines. He dragged his finger on the glass, and the thing rotated around, showing that it was three-dimensional; he swiped, he zoomed, he tapped, and things happened. “It’s a work in progress,” he said shyly, “but with time and resources, we should be able to build it out.”
Erszebet looked profoundly insulted. “You are saying you can replace me with a machine?”
“Not you. Your számológép,” he said. “Except even better.”
Every so often, Frank said exactly the right thing. This was one of those times. Erszebet’s face softened. She reached out for the iPad. He handed it to her. She pulled it into her lap and gazed at it in fascination. Her fingers began to move across the glass, halting at first, but quickly gaining fluency.
“Dude, that’s sick,” said Mortimer reverently.
“That’s beautiful,” said Julie the Smart-ass Oboist, pausing at our table with a pitcher of red ale and a platter of onion rings. “That looks like my grandmother’s Yao Jìsuàn qì”—and before any of us could think to question her, she had moved on to deliver her burden to a table of bearded CS nerds scholars.
Oda-sensei went on: “If we’d had something like this in place, fully realized, for the Bay Psalm Book gambit, for instance, it might have predicted the possibility of the maple syrup boiler being there if we didn’t first go back to the earlier DTAP and deal with Sir Edward Greylock and his investment schemes. It might have predicted the danger of Christopher Marlowe being in the Tearsheet Brewery that day.”
“It would take forever to imagine all such possibilities!” I objected.
“It’s not just about imagining,” he replied. “We can integrate this with historical databases, and we can improve those databases as we go back in time and learned what actually happened.”
“I don’t know,” I said. “We have all just had a very sobering lesson as to why nobody should rely on diachronic travel, ever, and instead you respond by saying, ‘Oh, let’s find a way to rely on diachronic travel.’”
“I’m pretty beat up,” Tristan admitted. “But I’ll bet the first person to survive an airplane crash, a hundred years ago, was pretty beat up too. You can limp away from the crashed airplane saying, ‘Man wasn’t meant to fly, I am done with this,’ or you can be saying, ‘I just learned how to do it better next time.’”
“What’s the point of it? Why even bother?” I asked. “We went to all of that e
ffort, and people died, so we could make fourteen million bucks. We’d have been money ahead if we’d just founded a tech start-up instead.”
“There are other powers in this game too,” Tristan said, “who can do what we can do, and who most definitely think there’s a point. We can’t let them have a monopoly on this kind of force.”
“So it’s back to the Magic Gap argument.”
“In a word, yes.”
Erszebet had been oblivious to the conversation ever since she had seized the iPad, but now she broke in with a question for Frank. “So many different colors and shapes of little blobs! What is this one? The little white cloud with the question mark?”
“That’s where the system is telling us it needs more input.”
“Input?”
“Information about something that happened in the past.”
“It knows about known unknowns?” Tristan asked. I gave a little snort, thinking he was making a joke at poor Les Holgate’s expense, but it seemed he was serious.
“Yes,” Oda-sensei responded, “this is a case where we would have to send a DOer back to collect information.”
“Holy crap,” Tristan said. “How much computational power—”
“More than can fit in an iPad,” Frank answered, cutting him off. “This is linked to a small cluster running in the cloud. But it’s still just a toy. It needs to be scaled up radically. To be really useful, it will take an immense amount of computing power.” With an almost impish smile, he added, “We’re gonna need a bigger quipu.”
PART
THREE
EXCERPTS FROM
SENATE INTELLIGENCE COMMITTEE HEARING
ON PROPOSED EXTENSION OF BLACK-BUDGET FUNDING
PROGRAM FOR DIACHRONIC OPERATIONS
DAYS 573–576 (LATE FEBRUARY, YEAR 2)
SENATOR HATCHER: Professor Oda, I draw your attention to this rather large document that was produced by DODO staff during the post-mortem analysis phase from the Les Holgate tragedy. Are you the author of the section of the report entitled “Diachronic Shear: A Layman’s Guide”?
FRANK ODA: Yes, I am.
HATCHER: To be frank, as a confirmed layman, I found that your explanations only made me more perplexed than I was to begin with. I have some questions about this.
ODA: I’ll try to be of service.
LIEUTENANT COLONEL LYONS: Senator Hatcher, if I may just insert a brief remark—
HATCHER: You may.
LYONS: This phenomenon isn’t well understood by anyone just yet. All we know is that it exists. We’ve seen it ourselves, and witches have attested to it. So any scientific hypothesis should be regarded as preliminary.
HATCHER: Thank you for that careful hedging, Lieutenant Colonel Lyons. I’m sure that your subordinates appreciate your paternal concern for their well-being. But I wish to address Professor Oda if that is fine with you.
LYONS: Of course. Thank you, Senator Hatcher.
HATCHER: Professor Oda, would you be so good as to explain the relationship of Jell-O to Diachronic Shear?
ODA: Excuse me, Senator. Jell-O?
HATCHER: Yes, it says here on page 793, third paragraph, that the properties of Jell-O, as in, Jell-O brand gelatin desserts, have something to tell us about the structure of the universe. And I found that to be a somewhat unusual statement from a man of science. I was wondering if you might elucidate it.
ODA: Yes, I remember that section. Traditionally we have tended to think of the past, present, and future as parts of a single continuous line—a thread, if you will.
HATCHER: And if I may just interrupt you there, Professor Oda, we have already been over this topic of quipus and so on ad infinitum, so we don’t need to belabor any more the idea that it’s not just a single thread but a whole network of them. I think that I understand it as well as any non-scientist can understand such a thing. Just as I felt I was achieving some level of comfort with that idea, you jumped to Jell-O. My great state happens to be home to no fewer than three different state-of-the-art industrial facilities that are part of the supply chain for Jell-O brand gelatin desserts and so naturally my interest was piqued. But I’ll be darned if I can follow your reasoning here.
ODA: If you have ever observed the properties of Jell-O, such as a molded dessert made of that substance—
HATCHER: I have, Professor Oda, on many occasions on the campaign trail.
ODA: You’ll know that it is flexible and deformable, up to a point. You can tap it with your spoon and it will jiggle. You can stretch it. But if you overdo it, the material will rupture. A crack will form, just like a crack in a block of stone. Later on, the crack may heal itself—the gelatin can knit itself back together.
HATCHER: Especially if you reheat it.
ODA: Exactly. Which is not true of cracks in granite and other brittle materials.
HATCHER: It is truly a marvelous property of Jell-O.
ODA: You could say so, yes.
HATCHER: But what is the relationship to this dreaded phenomenon of Diachronic Shear?
ODA: Viewed from the standpoint of the many-worlds interpretation of quantum mechanics, you could think of the past as being not a single thread but—
HATCHER: A quipu, yes, we’ve been over that.
ODA: When the quipu becomes sufficiently vast, it becomes instructive to transition, in our thinking, to a different mode, a continuous as opposed to discrete model, in which all of the threads effectively merge into a block of stuff that I am likening to Jell-O. When we send DOers back in time to carry out DEDEs, it’s like tapping the Jell-O with a spoon and making it jiggle a little bit. It creates internal stresses that the material is capable of withstanding. But if we try to change too much, too fast—
HATCHER: It cracks?
ODA: Yes.
HATCHER: It just splits wide open.
ODA: Just for a moment. But unlike a Jell-O dessert on your plate, the space-time continuum cannot simply fall apart. It is self-healing. The cracks must be sealed immediately. If you are far away from the crack, then you are safe—it’s like being far away from an earthquake. But if you are unlucky enough to be right along the crack boundary, then you are in for a bad time. The universe needs to decide whether you are going to go on existing or not.
HATCHER: You’re referring here to the so-called Tearsheet Brewery. What happened in that scenario?
ODA: You might think of the Tearsheet Brewery as like a lettuce leaf embedded in a Jell-O molded salad. Because of the unfortunate chain of events, this piece of lettuce was yanked out of the Jell-O and ceased to exist. A vacancy was left in its wake, which self-healed with the most terrible consequences for those unlucky enough to be near it.
HATCHER: Terrible consequences, indeed. Thank you, Dr. Oda. Madame Chair, I yield my time.
CHAIRMAN ATKINSON: Are there any further questions for Dr. Oda at this time? No? Very well, you may step down, Dr. Oda.
SENATOR COLE: Madame Chair, in light of Dr. Oda’s remarks I would like to call Lieutenant Colonel Lyons back.
[REDACTED]
SENATOR COLE: . . . the descriptions of the Tearsheet Brewery event are, in sum, so bloodcurdling, and the benefits of this mission so trivial in comparison—the recovery of an old book from a cask in Dr. Oda’s backyard!—that it must call into question why we are being asked to spend the taxpayers’ money on this sort of undertaking at any level, to say nothing of the exorbitant requests embodied in this proposed budget.
CHAIRWOMAN ATKINSON: I would like to thank my distinguished colleague for that impassioned, eloquent, and thorough statement. Was there a question for Lieutenant Colonel Lyons?
COLE: Why should we spend the taxpayers’ money on building a device that will only expose this great nation to additional risk?
LIEUTENANT COLONEL LYONS: Thank you, Senator Cole. For high-level strategic questions I might refer you to General Frink, but I’m happy to address your question on a more nuts-and-bolts level. As you point out, we need to keep the costs as low as possibl
e while minimizing risk and maximizing benefits. From a cost point of view, I’ll remind the committee that the only work being actively funded right now, and for the next few months, is CRONE: Chronodynamic Research for Optimizing Next Engagement. We have cut back the number of DEDEs to the bare minimum needed to sustain progress and we have limited those to missions of an exploratory or experimental nature. Most of our current budget is devoted to pathfinding work on the Chronotron, a device whose entire purpose will be to minimize risk.
COLE: To minimize risk, you say.
LYONS: Yes, Senator. That is its purpose.
COLE: Both Dr. Oda and General Frink in their earlier testimony praised the Chronotron as a tool that would enable DODO to plan future missions. Would you concur?
LYONS: Yes, it duplicates the functionality of the quipus or other similar devices used by witches to navigate the different Strands of history, and combines that with a colossal database of historical facts. If we’d had it earlier, we’d have planned our first DEDEs differently and gotten results more quickly and more safely.
COLE: Or perhaps chosen some different DEDE altogether?
LYONS: Yes, it’s quite possible that with a functioning Chronotron we might have been able to identify something both easier and more profitable than recovering a Bay Psalm Book.
COLE: This is precisely what concerns me about building the Chronotron.
LYONS: I’m sorry, Senator Cole. Why would you be concerned about DODO having a tool that would enable us to make more informed choices? As opposed to just winging it?
COLE: When you just wing it, you are aware of the risk and the uncertainty, and inclined to be more cautious. When you have a high-tech tool giving you an illusion of omniscience, I am concerned that it will lead to greater risk-taking.
LYONS: I would argue that more information is always better. I would make an analogy to using computers to predict the weather. Back in the days when all we had was a weathervane and a barometer, a ship’s captain had to make his best judgment about what the weather was going to do, and trust his gut. Now that we have weather satellites and computerized forecasts, the captain can make informed decisions.