Iterations and other stories (collection)

“They won’t need any records.” Why couldn’t she see this? “A human being consists of about thirty thousand active genes. That means that there are about three-to-the-millionth-power possible genetically distinct humans. And there are about 2-to-the-10th-to-the-I7th power possible human memories. Multiply it all out, and you’ll find that you could reproduce all possible versions of our world—including every possible combination of human beings, with every possible set of memories—in 10-to-the-10th-to-the-123rd bits.”

“Ten to the tenth to…”

“To the 123rd, yes,” I said. “And that amount will surely eventually be computable. Meaning that you could—well, Tipler used the word ‘resurrect,’ and that’s as good as any—you could resurrect everyone who ever lived as computer simulations, without knowing anything specific about them.”

Mary looked at me. “And you think that’s what we are? Resurrected versions of people who died billions of years ago?”

“We have to be. It’s the only thing that explains the absence of extraterrestrial probes here, or of radio signals from other civilizations. To simulate Von Neumann probes—that’s what those self-replicating robots are called—and the chatter of alien races would mean simulating the rest of the universe, with its billions of different lifeforms. But they don’t have enough computer memory—or, if they do, they consider it wasteful. So, yes, this world seems real to us, but it’s fake. It has to be.”

“Oh, Erik,” said Mary, shaking her head, then letting out a sigh. “Go to sleep.”

She kissed me and lay down.

I lay down too, but it was hours before I fell asleep.

If I’m a computer simulation, created millions or billions of years in the future of what I think of as the present, and if I was created simply as one possible human being with one possible set of memories, do other versions of me exist?

Did the simulators—whoever they are—pick one state of humanity at random for their experiment? Maybe. But Tipler said they would actually simulate all the possible states.

And if they did—

If there are other versions of me—

All the horrid things I’d ever thought about doing: the stealing, the cheating, and, yes, the murders. In other parts of this vast computer simulation, there must exist other Erik Hansens who had done those things. Some, of course, will have been arrested for their crimes, and will be paying their debts to their simulated societies.

But others…

I once heard a statistic that ninety percent of men would commit rape if they felt sure they could get away with it. I’d never believed that figure; rarely did I meet an attractive woman that I didn’t have at least a passing thought about having sex with, but never would it occur to me to force myself upon her.

Well, almost never…

If they had simulated this me, they could have simulated that me, too—indeed, all the other possible mes: a me who had raped Connie Hughes in high school, when she hadn’t wanted to go as far as I’d wanted to; a me who had stolen a thousand dollars from Gideon Dillings; a me who…

Mary and I hated to even mention his name: my bête noire, the bane of my existence. Roscoe Harada, that goddamned son of a bitch…

Yes, the version of me who had done what I had fantasized about doing. The version of me who had caved in Harada’s brow-ridged cranium with an aluminum baseball bat…

And the version of me who had shot him in the face, watching his skull open up like time-lapse film of a rose blooming…

And the version of me who had pushed him off the Bloor Street viaduct, letting him fall to the Don Valley Parkway, his body going splat, and then being run over by car after car after car…

They were all conceivable memory states. And if they were possible, then perhaps they did exist in other iterations of this simulation.

And that was intolerable.

It took a while to work it out, but I could now slip between worlds. I rather suspect the designers of the simulation didn’t know I was doing it. Sure, murders were occurring as I eliminated other versions of myself—versions whose existence I couldn’t countenance. But murders happen all the time. And if there were billions of versions of reality, well, on any given day, the same person would be snuffed out in millions of them anyway.

As I’d guessed, the simulators apparently had constraints on how much memory they could use, and so had decided to reconstruct Earth but none of the rest of the universe—at least not in any detail. And since there were memory constraints, some sort of data compression was being employed. Whenever the operating system saw that there were two or more identical versions of any given object, rather than code them both twice, it apparently would code only one version and simply put a pointer to it in the other iterations of the simulation.