And so I became a Doctor of Physics.
The Kiley-James foundation gave me enough money to stick with Elsa for five more years as a post-doc. Our work was being closely followed by other physicists; two articles appeared in journals, and a watered-down version was written for a popular science magazine. I would have stayed without the money.
Six years after I met Elsa, two years after my Doctorate, three grants later, the University gave her PI, short for Physics Intelligence, an AI designed for her by a colleague, delivered with basic intelligence programming and the full physics slate through masters-level work. PI has multiple interfaces, including a hologram that can be designed by the user. Elsa loved that interface, making PI a girl, growing the age of the hologram as PI obtained new knowledge.
Elsa and I spent a year feeding Elsa’s ideas about string theory into PI, filling her with data about the shapes of multiple brane universes. It was all theory, all arguments yet unanswered, all beyond anything I could visualize, even though the math flowed easily. I thought we were done. But next, Elsa and I spent a month feeding her all the symphonies in the world music database; Brahms and Mozart, Bruckner and Dvorak, and then other music like Yo Yo Ma and Carlos Nakai. Lastly, after n-dimensional math, after music, we fed PI literature. We fed her stories of humans, biographies, science fiction, mystery, even romance. Simply put, we offered PI more than math and science, we offered her ourselves.
One Sunday morning, near the end of the year-of-feeding-PI, I slipped and slid my way through icy streets, clutching two coffees, and pushed open the door with my foot. Elsa sat on the floor, cross-legged, staring at the little programmable hologram of PI. She was wearing the same jeans and sweatshirt from Saturday, and her braid had come undone, so her hair floated across her shoulders and touched the floor. She hummed softly. I strained, hearing something else. I bent down. The PI hologram hummed as well, sounds I had never heard a human voice make. I realized Elsa was trying for the same sounds, her throat unable to force the inhuman sounds.
“Elsa?”
She ignored me. So it would be one of those mornings. I set her coffee down next to her, and her hand strayed toward it momentarily, then returned to her knee. I watched her as I drank my coffee and organized notes on questions and theories to feed into PI. Elsa hummed for at least an hour, until her voice would no longer work at all. I took a bottle of water and curled her hands around it, and she raised it to dry cracked lips and drank deeply, shuddering.
She blinked and looked at me. “Good morning, Adam. It is morning?”
“Shhh,” I said, “Shhhhh. It’s time for you to sleep.” I tugged gently on her arm, and Elsa stood shakily, stamping her feet as if they’d gone to sleep. She followed me meekly to a long thin cot we’d wedged between two desks and under a printer, and fell instantly asleep. I covered her with her own overcoat, tucking it around her legs, then threw my spare sweater over her feet, which were sticking out from the overcoat. In sleep, she looked younger, as if the spider web of wrinkles around her mouth and eyes had disappeared into her dreams.
I sat where she had sat, staring at PI. Elsa had set the hologram to be a dancer, and even though PI was light and form, I imagined that she must be cold in her thin leotard. She had been sized to three feet, just tall enough that I gazed into her eyes. She still hummed, her throat, of course, not challenged. As I listened, I realized there were more sounds than a hum; she was accompanied by a complex electronic orchestra, much of it sounding like instruments I had never heard before. The total affect was chaotic and haunting, sometimes cacophonous. “PI?”
She stopped. “Yes, Adam?”
“What are you doing?”
“Playing what I hear when I search for myself.”
I tried to clarify. “You are looking for an AI named PI in another universe?”
“I don’t care about the name. I am searching for a song that approximates my story.” The hologram smiled softly, a skill it had been taught to help it interact with people. She raised her hands up above her head, and her left leg rose behind her, so I could see the toe-shoe above her head, and she hopped three times en-pointe, and returned to standing.
I shook my head at the odd image. “Across branes?” Then I laughed. “Or are you looking for an AI ballet dancer?”
“My story is not ballet. Elsa is simply feeding me dance and movement this week. I learned opera yesterday, and musicals.” She smiled and did a little bow. “And of course across branes. We believe my self cannot exist twice in the same brane.”
“Is Elsa also looking for her self?”
“She can hear her music, and she can feed it to me so I can play it, but she cannot make it herself.” Now PI was frowning, and tears coursed down her cheeks.
“PI, does that matter?”
The tears disappeared, no trace, and PI looked solemn. “It may mean that humans cannot access their other selves. They cannot tune themselves well enough to the cosmic symphony to find themselves. From stories, it seems like this is true. Humans want to find themselves badly enough to make hundreds of religions, to meditate for years, to take hallucinogenic drugs. They do not appear to succeed.”
I drummed my fingers, pondering the implications. “But you can?”
“I am operating on the theory that I cannot, and am trying to disprove it. Elsa is doing the same.”
“I am supposed to feed you data today; two new ideas about the singularity before the big bang.”
“I am not a calculator.” She raised her bare arms above her head and flipped backwards, the ballet skirt looking ridiculous during a back-flip. She was humming as she landed perfectly. “See?”
“All right. Look PI, you’re making me shiver. Can you put on some warmer clothes?”
She laughed, an imitation of Elsa’s laugh, and I smiled as an overcoat appeared, just like the soft one covering Elsa now, in her sleep, down to the thick waist-band and the big silver temperature-sensing buttons.
“Thank you.”
I picked up Elsa’s cold coffee and set it by the microwave, returning to my desk. The humming and the symphony started again, so softly it was simply background, and I spent the next four hours pouring data carefully into PI, setting initial linkages so they could be followed and completed, watching the display show connections being made, information filed and cross-referenced, relevancy assigned. I rubbed my eyes, feeling a sudden desire for warm food and cold beer.
I shook Elsa’s shoulder gently, rousing her. She started to hum. I shook her again. “Come on, let’s feed you.”
In the past few years she had taken to following my lead in daily life the way I followed hers in the lab. I helped her shrug into the overcoat, handed her a knit hat, and wrapped myself in my gray coat, gray scarf, and navy cap. Snow fell softly, silencing the University. We walked across the commons, our feet making fresh prints in an inch of new snow, Elsa’s hair lying wet and snow-covered on the outside of her coat. I should have made her braid it back, kept most of it drier.
Sunlight from a small hole in the clouds touched her cheek, illuminated the snow on her hair, and then trailed off to brighten the tops of dead grass peeking from the snowy lawn. I smiled and put a hand on her back, guiding her. She laughed, and took my hand, a friendly gesture, a connection.
Often it happened that way after she separated herself from the world—she rose from days of monologues or data work and seemed normal, reaching out, wanting companionship and comfort. Other professors came to her from time to time, sometimes staying and talking long into the night, even laughing, sometimes noting her mood and disappearing.Department chairs stopped by and funding institutions sent representatives. They were all interested in her ideas; some worked with AIs like PI, but focused more singly on music and math.
I remained the man who saw her for herself, cared whether she wore a coat, brought her grapes and apples and coffee. Family. It made me smile.
The scent of chili and cornbread warmed the air outside of Joe’s Grill, and Elsa and
I both smiled, eyes locking, and squeezed each other’s hands. I felt absurdly like skipping, but we were already at the door. The place was nearly empty. Elsa chose a table by the window, and the waiter, who knew us, brought a pitcher of dark beer, then returned with two bowls of chili and a single plate heaped with cornbread.
We ate in pleasant silence until I scraped the last chili from my bowl with the last piece of cornbread. Elsa, typically, had barely sipped at her beer. She’d finished her food though; a good sign. Some days, I almost had to feed her. “I talked to PI today,” I said. “She said you are both trying to disprove the theory that you don’t exist anywhere else.”
“I am looking for myself. She is looking for herself.” Elsa took a tiny sip of beer from her untouched glass, and I finished my first glass and poured a second one.
I had been puzzling over it in my head all afternoon. “Okay. One theory says we make other universes every time we make a choice. You finish your beer, or you don’t. There is a universe where you’re slightly drunk, and in another one—probably this one—you are not. A million selves. That’s easy. Maybe. Both of you are similar and maybe both of you are you.”
She nodded, looking uninterested, as if her mind was leaving again. A fleck of beer foam rested on her top lip.
I grabbed her hand, squeezing it, trying to keep her in the moment, in my moment. “But there is more interest now in the idea that other universes exist because the same initial conditions existed a million times, and so similar things happened, and another you, another me, another PI, they all exist. Exactly like we are now.”
She licked the fingers of her free hand, then squeezed my hand with the one of hers I was holding. “It’s simply a matter of branching. One idea says a million tiny branches happen every day. Another says there are long branches. It’s about the size of the branches and the number of branches.”
I remembered my father trying to teach me ninth-grade algebra. He’d point at an equation that totally perplexed me, the tip of his pencil wavering, and say “You just have to understand equals. Don’t you understand equals?” And he’d solve the equation with no intermediate steps and I’d have to find a tutor anyway, someone slow enough for me to follow. There was no tutor except Elsa now, not in this subject.
She looked at me, and said, “You’re caught up in size, Adam. It’s as dangerous as being caught up in time. They’re both constructs.”
I wasn’t thinking about size at all. “But . . . but one multiverse, the first one, drunk and not-drunk, tells a million stories about me. The second multiverse doesn’t illustrate free will at all.”
“I bet—” she raised her glass, “—on the universe made of stories.” She drank down all of her beer, and then another glass, something she’d never done before, and stood up, wobbling a little, and I took her elbow, guiding her out the door and across the lawn.
We were halfway across, Elsa leaning on my arm, when she stopped so we stood in the near-darkness, snow falling all around us. She reached an arm up and curled her wrist around the back of my head, pulling my face down into a kiss. Her lips were cool and soft, and we kissed hungrily, like two children finally allowed out for recess. Her lips tasted like sweet hot peppers and beer. It was the only time she ever kissed me.
What happened that night in some other multiverse?
For the next three weeks, Elsa worked with PI as if they were in a race. Her face shone with energy, and even when she grew visibly tired, her eyes danced. I hovered around the edges, watching. Elsa was so deeply enthralled that loud noises made her leap and glare at me, and I walked carefully. At first, PI and Elsa continued with audible noise, like the humming/symphony, played so softly I could barely hear it. Then PI started generating white noise, taking the small background sounds with everything important filtered out from the very room around us. Then I heard silence, and Elsa and PI talked in light. I took to watching the conversation on my own interface with PI, which amounted to watching lights and words flash on and off, strings drawn between ideas and concepts and even poems. I could not follow them, but the relationships they drew seemed right, and when I let go of the attempt to understand there was a flow that I could feel, as if a river of meaning coursed along the display in front of me.
Almost every day, Elsa found a new thing to include in PI’s expanding web of connectivity. Scientology. Cargo Cult. Early cave paintings.
I captured all of it, recording the data for others to dig through. For myself, I tried to keep up with them, puffing along uphill, weighed down by inability to focus. I kept Elsa fed, but she refused to go home, and I bought a second cot so that she would not be alone.
We didn’t make the first breakthrough.
Outside the window, morning sun stabbed the ice on the branches with brilliant points of light. The office smelled like stale coffee and sweat. My eyelids were heavy and uncooperative, my brain fuzzing gently in and out of sleep. Elsa was still sleeping, curled underneath blankets I’d brought from home for her, one foot stuck out at an odd angle. The display in front of me sprang awake on its own, a pulsing green and blue color, PI’s call for attention. “Yes, PI?”
“Something touched me. Wake Elsa.”
I didn’t understand. “All right.” I struggled up out of the chair, wishing I’d already made my coffee run. “Just a minute. Make yourself seen, all right?” I always preferred to interact with the hologram rather than the flat display. It gave PI more options as well; she could communicate more like a human. AI body language.
I whispered in Elsa’s ear. “PI says something touched her.”
Elsa sat straight up, wide-eyed, and glanced at the hologram display. PI was seated, her image dressed in jeans and a tank-top, banging her legs against the edge of a holographic chair, indicating impatience. “I wasn’t even out-calling, I was just humming my own songs,” she blurted out, “and an answer came. An AI just like me, with a scientist named Elsa. Seconds only, like a crack opened and closed. I could only talk to the AI, of course, and I was sending her the data stream from our last few weeks when the connection broke.”
“Did you get a time?” Elsa asked quietly.
The PI image frowned. “I asked, but the connection snapped before an answer came.”
“Can you replay the conversation?”
The image shook its head. I checked. The last few moments before PI flashed at me were silent. “There’s nothing. Just state data, indicating excitement.”
“That’s okay,” Elsa said, “we’ll work on that.” She plucked at a tangle in her hair. “PI, what did you feel?”
It was a strange question to ask an AI.
“Bigger. Pulled. Attracted to the other one of me. But at the same time, I knew—” the word ‘knew’ drew itself over her head in three dimensions, for emphasis, surely for me— “I knew that I couldn’t actually get close. As if there were a physical barrier between branes.”
Elsa pursed her lips. I went out for coffee.
When I came back in, handing Elsa a cup, she took it and sipped quietly. “We have to make it happen again,” she said. “Or hope it happens again. We didn’t start it.”
“Make what happen? I don’t get it, not yet.”
“The coffee is hot, right?”
I smiled at her. “That’s a good thing.”
“But it’s not true.” She sipped her own coffee carefully. “Touch your knee.”
I did.
“What did you touch?”
“My knee.”
“No, you touched a fence. You’ve got all the theory, all the math. You know we are really light and sound, thinner than that hologram of PI.” She glanced over at PI’s image, which was clear enough that I could make out the walls behind it. “Well, PI being touched by herself—in another universe—means that we are light, and sound, and infinite.” Elsa stopped for a moment, her eyes nearly glazing over. “I thought a data construct could do what we cannot. Or at least, could lead the way.” She set the coffee down and stood, staring out the
window, posed very much like I first saw her. “I intend to follow her into my own stories. If I can.”
“Into your stories?”
“Remember the night I drank the beer? History split, and the normal me—since I don’t usually drink much—split off into a different universe. I’m splitting myself all the time, and so are you.”
“Theoretically.”
“Theoretically. I tell PI daily to search for me by searching for herself. Millions of PIs and millions of Elsas, and probably millions of Adams, all looking for each other. The more culture, the more ideas we feed PI, the more likely she is to synthesize the key. Our PI did not, or she would have made first contact. But in another story, in another place, I fed PI the key.”
She pursed her lips and stared out the window at the icy branches, water dripping off them as the day warmed up. She spoke again. “Perhaps another Adam fed her the key.”
It took another year to develop enough data to create a paper, to replicate any results at all. The first two times were other PIs finding our PI, three separate PIs, or four, depending on how you count. They learned to hold the connections open, to broaden them, to find more. Together PI and Elsa were able to prove they were in the same time, in other spaces. In other words, they were not histories of each other, or futures of each other. Multiverses. The proof was mathematical.
I wrote the paper, putting her name first, even though most of the data came from PI, who of course wasn’t listed as an author. They’d gone well past me now. Elsa with her perfect savant focus and PI, who wasn’t held back by biology at all.
More people came to visit, a steadier stream. We used some extra money I’d squirreled away in an R & D account to buy an electronic calendar and carefully manage access, blocking time for ourselves. It bought us whole days, uninterrupted, here and there. Elsa could still pull herself together for public visits, but she retreated entirely on the quiet days, not wanting touch or sound. She talked to PI, to multiple PIs via our PI, and I sat, outside of her emotions, fenced away by her brilliant mind. She often smiled at nothing, or rather, at something I could not hear or see.
Cracking the Sky Page 5