Beyond our sphere of light—absolute darkness.

I stop, awestruck and speechless.

I think of the thousands of articles and books I’ve read in my lifetime. Tests taken. Classes taught. Theories memorized. Equations scribbled on blackboards. I think of the months I spent in that cleanroom trying to build something that was a pale imitation of this place.

For students of physics and cosmology, the closest one can ever get to the tangible implications of research are ancient galaxies seen through telescopes. Data readouts following particle collisions we know occurred but can never see.

There’s always a boundary, a barrier between the equations and the reality they represent.

But no more. Not for me at least.

I can’t stop thinking, I am here. I am actually in this place. It exists.

At least for a moment, fear has left me.

I’m filled with wonder.

I say, “ ‘The most beautiful thing we can experience is the mysterious.’ ”

Amanda looks at me.

“Einstein’s words, not mine.”

“Is this place even real?” she asks.

“What do you mean by ‘real’?”

“Are we standing in a physical location?”

“I think it’s a manifestation of the mind as it attempts to visually explain something our brains haven’t evolved to comprehend.”

“Which is?”

“Superposition.”

“So we’re experiencing a quantum state right now?”

I glance back down the corridor. Then into the darkness ahead. Even in the low light, there’s a recursive quality to the space, like two mirrors facing each other.

“Yeah. It looks like a corridor, but I think it’s actually the box repeating itself across all possible realities that share the same point in space and time.”

“Like a cross-section?”

“Exactly. In some presentations of quantum mechanics, the thing that contains all the information for the system—before it collapses due to an observation—is called a wave function. I’m thinking this corridor is our minds’ way of visualizing the content of the wave function, of all possible outcomes, for our superposed quantum state.”

“So where does this corridor lead?” she asks. “If we just kept walking, where would we end up?”

As I say the words, the wonder recedes and the horror creeps in: “There is no end.”

—

We keep walking to see what happens, if anything will change, if we will change.

But it’s just door after door after door after door.

When we’ve been going a while, I say, “I’ve been counting them since we started down the corridor, and this is the four hundred and fortieth door. Each box repetition is twelve feet, which means we’ve already gone a full mile.”

Amanda stops and lets the backpack slide off her shoulders.

She sits against the wall, and I take a seat beside her, with the lantern between us.

I say, “What if Leighton decides to take the drug and come charging in here after us?”

“He’d never do that.”

“Why?”

“Because he’s terrified of the box. We all are. Except for you, no one who went inside ever came out again. That’s why Leighton was willing to do anything to make you tell him how to fly it.”

“What happened to your test pilots?”

“The first one to enter the box was this guy named Matthew Snell. We had no idea what we were dealing with, so Snell was given clear and simple instructions. Enter the box. Close the door. Sit. Inject himself with the drug. No matter what happened, no matter what he saw, he was to sit in the same place, wait for the drug to wear off, and walk right back out into the hangar. Even if he had seen all this, he wouldn’t have left his box. He wouldn’t have moved.”

“So what happened?”

“An hour passed. He was overdue. We wanted to open the door, but we were afraid of interfering with whatever he was experiencing on the inside. Twenty-four hours later, we finally opened it.”

“And the box was empty.”

“Yep.” Amanda looks exhausted in the blue light. “Stepping into the box and taking the drug is like walking through a one-way door. There’s no coming back, and no one’s going to risk following us. We’re on our own here. So what do you want to do?”

“Like any good scientist, experiment. Try a door, see what happens.”

“And just to be clear, you have no idea what’s behind any of these doors?”

“None.”

I give Amanda a hand up. As I hoist the backpack onto my shoulders, I note the first mild twinge of thirst and wonder if she brought along any water.

We head down the corridor, and the truth is I’m hesitant to make a choice. If there is an endless possibility of doors, then from a statistical perspective, the choice itself means everything and nothing. Every choice is right. Every choice is wrong.

I finally stop and say, “This one?”

She shrugs. “Sure.”

Grasping the cold, metal handle, I ask, “We have the ampoules, right? Because that would be—”

“I checked the pack when we stopped a minute ago.”

I crank the lever down, hear the latch bolt slide, and pull back.

The door swings inward, clearing the frame.

She whispers, “What do you see out there?”

“Nothing yet. It’s too dark. Here, let me have that.” As I take the lantern from her, I notice that we’re standing in a single box again. “Look,” I say. “The corridor collapsed.”

“That surprises you?”

“Actually, it makes perfect sense. The environment outside the door is interacting with the interior of the box. It destabilized the quantum state.”

I turn back to the open door and hold the lantern out in front of me. All I can see is the ground directly ahead.

Cracked pavement.

Oil stains.

When I step down, glass crunches under my feet.

I help Amanda out, and as we venture the first few steps, the light diffuses, hits a concrete column.

A van.

A convertible.

A sedan.

It’s a parking garage.

We move up a slight incline with cars on either side of us, following the remnants of a white paint stripe that divides the left and right lanes.