PART ONE

“In the far reaches of an infinite cosmos, there’s a galaxy that looks just like the Milky Way, with a solar system that’s the spitting image of ours, with a planet that’s a dead ringer for earth, with a house that’s indistinguishable from yours, inhabited by someone who looks just like you, who is right now reading this very book and imagining you, in a distant galaxy, just reaching the end of this sentence. And there’s not just one such copy. In an infinite universe, there are infinitely many. In some, your doppelg?nger is now reading this sentence along with you. In others, he or she has skipped ahead, or feels in need of a snack and has put the book down.

In others, he or she has, well, a less than felicitous disposition and is someone you’d rather not meet in a dark alley.”

Brian Greene, The Hidden Reality

CHAPTER ONE

When the multiverse was confirmed, the spiritual and scientific communities both counted it as evidence of their validity.

The scientists said, Look, we told you there were parallel universes.

And the spiritual said, See, we’ve always known there was more than one life.

* * *

EVEN WORTHLESS THINGS can become valuable once they become rare. This is the grand lesson of my life.

I’m at the base of a mountain, looking over a landscape I was never meant to see. On this Earth—number 197—I died at three months old. The file only lists respiratory complications as cause of death, but the address on the certificate is the same one-room shack where I spent most of my life, so I can picture the sheet-metal roof, the concrete floor, and the mattress my mother and I shared on so many different Earths. I know I died warm, sleeping, and inhaling honest dirt off my mother’s skin.

“Cara, respond. Cara?”

Dell’s been calling me, but she’s only irritated now and I won’t answer until she’s concerned. Not because I like being difficult—though, there is that—but because her worry over a wasted mission sounds just like worry over me.

    Behind me, information is downloading from a stationary port into a mobile one. When it’s done, I’ll take the mobile back to Earth Zero, our primary Earth, the one the others think of as real. The information I gather is divided up into light data—population, temperature fluctuations, general news—and dark data—what is affecting their stocks that might affect ours, or, if it’s a future world, a full listing of where every stock will close on a given day. The existence of the dark data is a big secret, though I don’t know why anyone would care. Insider trading doesn’t even sound like a crime—not a real one, one with blood.

“Cara…”

Still just annoyed. I check the download’s progress. Sixty percent.

“Cara, I need you to answer me.”

There we go.

“I’m here.”

There’s a pause while she resets to apathy, but I heard the panic. For a second, she cared.

“You don’t always have to leave me waiting.”

“And you don’t always have to plant me two miles from my download port, but I guess we’re both a little petty, eh Dell?”

I can hear her smiling but not smiling from 196 worlds away. I’ve dodged the physical training for my job since just after my hiring six years ago. She’s so uptight, you’d think she’d just report me, but forcing me on these long walks is her answer.

“You’re wanted back. There’s a file on your desk.”

“I already have my pulls for the week.”

“Not a pull. A new file.”

“No, but…”

I put my hand against my chest, expecting to feel a divot, some missing chunk of flesh.

I want to tell her it can’t be true. I want to tell her I would have known. Instead, I tell her I need an hour and cut the link.

    If I have a new world, it means that particular Earth’s me isn’t using it anymore. I’m dead again, somewhere else, and I didn’t feel a thing.

I’m not sure how long I sit, staring out at a horizon that’s like mine, but not. The download dings its finish. I could traverse out from here, since there’s no one to see me, but I steal a little time exploring the place fate tried to keep from me.

Another me is gone. As I walk into the valley, I’m a little more valuable walking down the mountain than I was walking up.

* * *

WHEN I WAS young and multiverse was just a theory, I was worthless: the brown girl-child of an addict in one of those wards outside the walls of Wiley City that people don’t get out of or go to. But then Adam Bosch, our new Einstein and the founder of the institute that pays me, discovered a way to see into other universes. Of course, humanity couldn’t just look. We had to enter. We had to touch and taste and take.

But the universe said no.

The first people sent to explore a parallel Earth came back already dead or twitching and about to die, with more broken bones than whole ones. Some actually did make it through, and survived on the new world just long enough to die from their injuries and have their bodies recalled.

It took a lot of smart people’s corpses before they learned that if you’re still alive in the world you’re trying to enter, you get rejected. You’re an anomaly the universe won’t allow, and she’ll send you back broken in half if she has to. But Bosch’s device could resonate only with worlds very similar to our own, so most of the scientists—with their safe, sheltered upbringings in a city that had eliminated childhood mortality and vaccinated most viral illness into extinction—had living doppelg?ngers on the other worlds.

They needed trash people. Poor black and brown people. People somehow on the “wrong side” of the wall, even though they were the ones who built it. People brought for labor, or come for refuge, or who were here before the first neoliberal surveyed this land and thought to build a paradise. People who’d already thought this was paradise. They needed my people. They needed me.

    Of the 380 Earths with which we can resonate, I’m dead in 372. No, 373 now. I’m not a scientist. I’m just what they’re stuck with. The higher-ups call us “traversers” on paper. Using ports put in place by the last generation of traversers, we download the region’s information and bring it back for greater minds to study. No better than pigeons, which is what they call us, not on paper.

One day, the Eldridge Institute will figure out how to remotely download information across worlds, and I’ll be worthless again.

* * *

BACK ON EARTH Zero, I go straight to my floor after changing into my office clothes. Dell stands out tall in the herd of desks, more than two-thirds of them empty now. Her face is all tight because she’s been kept waiting by the only person who ever dares inconvenience her.

“Slumming it, Dell? I thought coming below the sixtieth floor gave you hives.”

She smiles, less like she thinks I’m funny and more like she wants to prove she knows how.

“I’ll survive.”

Of that, I can be sure. Survival is Dell’s whole problem. Here, on Earth Zero, she wanted to be a traverser. She was set up for it too: an air force pilot who’d had her eyes on space before the possibility of other worlds opened up. But Dell comes from a good family, one with money a long way back. In some worlds her parents never emigrated from Japan. In some she joined the private sector instead of this government-research-institute hybrid. But she survived in over 98 percent of other worlds, and in most of those she thrived. I’ve seen three dozen Dells, and all but one wore clothes more expensive than mine.

    When I take off my jacket, we both hide our wince. Bruises line my arms in jagged stripes, and those are just the parts she can see.

“It shouldn’t be this bad,” she says, her eyes moving between quadrants of my body like she’s doing hard math.

“It’s only because I’ve been doubling up.”

“Which is why I advised against it.”

“I need the long weekend.”

We’ve had this conversation five times this week and it always ends right here, where her concern is outweighed by the effort it takes to argue with me. She nods, but the look she gives my arms lasts long enough for me to notice. It’s when she notices my noticing that she finally looks away.