Try catch throw

Journal name:
Nature
Volume:
537,
Pages:
259–270
Date published:
DOI:
doi:10.1038/537259a
Published online

A difficult theory to displace.

TRY

The first thing Marielle does is reset their lives to the night Sam has the idea that will destroy the world. They are at Chianti's on West 4th. A small table near the back. He'd told her that their conversation during the date planted the seed of his experiment.

So here she is to uproot it.

CATCH

“I think we should move in together.”

Sam nearly spits out his wine.

It's a dramatic way to derail his train of thought — they've only been dating for six weeks. In their previous life, it took nearly three years to reach this point. After the mess her parents had made, all romantic relationships seemed provisional.

Sam is a committer though. Eyes lit. “You're not pulling my chain?”

“No chain,” she says. “No strings.”

TRY

It buys her eight months. An apartment on Maple Street. Two toothbrushes in the cup. She almost forgets the life they'd already lived. Then one evening she comes home late and he's at the kitchen table surrounded by familiar-looking diagrams. The floor drops out from under her.

“You had an idea,” Marielle says.

“I totally had an idea. Wait till I tell you.”

“Before you do, can you remember when you had it?"”

CATCH

Sam and Andy Wong carpool when Marielle has to stay late at the supercomputing centre where they all work. And of course they've been talking about how to prove the simulation hypothesis.

She resets a day and drives Sam home instead. Not enough. The conversation has been ongoing. She tries a week. A month. Still the diagrams on the table laying out a path to the end of everything.

She finally resets to before the carpool began and creates a convincing paper trail that suggests Andy Wong lied terribly on his CV. She sends it anonymously to the head of research.

Sam carpools with Kristin Kanz, the office manager. They share an interest in police dramas. They do not discuss computational physics.

TRY

Two years pass. Their relationship is different this time. Marielle finds she is more thoughtful, more open. She experiences things more deeply. The smell of food. The taste of salt on Sam's skin after he's been running.

She nudges him away from investigating the granular structure of space-time. Then he puts in a request for supercomputer access as part of his personal project allocation.

“We can do it in software,” he says, bubbling over.

She feels like she’s falling again. “How can you test if we're living in a simulation using software?” Maybe it will be a blind alley. But he has a brilliant idea about using nested simulations to predict the operating constraints of the machine the Universe could be running on.

Too brilliant.

CATCH, TRY, CATCH, TRY, CATCH

Marielle resets and proposes, three years ahead of schedule. They honeymoon in Europe. While on a tourist visit to CERN he gets a look on his face. “I just had a crazy thought about the simulation hypothesis.” He's hardly finished the sentence before she resets to four months earlier and convinces him to choose Thailand. She endures a second round of dress fittings and reception planning.

Two years more she holds it together. They had been childless in their other life, but this time there's Elle, and everything is so different.

One night, they've been up for hours. Finally their colicky girl is asleep. They sit on the floor of the nursery, toys strewn around them, legless with fatigue.

“Whoah,” Sam says. “I just had the wildest idea.”

“No.” Marielle snaps at him. “You do not have any ideas. You hear me? No ideas. No experiments.” She's shaking. She can't reset again. The past never happens the same way twice. Nature will roll the dice and give her a different child and Elle will be gone forever.

“It's just colic,” he says. “It'll get better.”

“Not if you keep going it won't.” So she tells him what happened when he proved they were living inside a simulation. The bargain she made to prevent the beings who ran the Universe from wiping it clean.

Afterwards there is a strange brightness in his eyes that she mistakes for fear. For grief.

TRY

Seven years later, Elle is at school. Marielle is home, ill. She uses Sam's computer to catch up on work and as she does his e-mail window pops up. It's an acceptance for his paper on the simulation hypothesis. The editor of the journal is effusive. He commends Sam for the years of work he'd put in.

Years.

Marielle puts her head on the table. She sobs and sobs.

THROW

She is suddenly in a grey room.

“I can do it — I can,” she says. “I managed for 12 years. Do you know how many times I reset?”

“Too many times.” The voice is as colourless as the room. “You could not prevent this knowledge from spreading as you promised. A wipe is required.”

“Wait,” she says, desperate. Elle will need picking up from school soon. Or is the Universe frozen when she's in the grey room? Paused while a finger hovers over the delete button. “Wait. There's still something.”

FINALLY

She resets to mid-pregnancy, when she and Sam were hiking. An autumn Sunday finds them at the top of Grouse Mountain. Marielle lags behind. Tells him it's the weight of the baby that slows her down, rather than dread.

They walk a narrow path. Even knowing what she knows, it's hard to believe everything is code. Elle, growing inside her. The sun in the blue sky. Her husband.

Sam stands on the cliff edge admiring the view. She is so close to him now.

She steps forward…

Author information

Affiliations

  1. Andrew Neil Gray has published work in Apex Magazine, IGMS and has a novella forthcoming with Tor.com. He won second place in the 2015 Quantum Shorts Competition.

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