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Comment by rubidium | Hacker News Reader

Fun fiction, unfortunately missing the boat on quantum computing capabilities, the aims of quantum simulation, and the way quantum mechanics works.

The current interpretation of quantum mechanics is completely at odds with the statement from the story: "'[the simulation] is still as accurate a simulation of the real universe as there can possibly be. Civilisation - indeed, all of history - should rise on this Earth precisely how it did in reality. There are no chances. It's all worked out to infinitely many decimal places.'"

That's just not quantum mechanics. The "infinitely many decimal places" is a classic mistake (pardon the pun) and indicates a strong deterministic bent to the authors way of thinking about the world.

Clearly, quantum indeterminacy and its implications for a non-deterministic universe are still hard to both understand and get right in fiction.

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I'm pretty certain the author knows quantum mechanics doesn't work like it does in the story. Consider:

Brute force primality testing of every single integer in existence? Easy. Pi to the last digit? Piece of cake. Halting Problem? Sa-holved.

This is obviously tongue in cheek, and only serves to establish that the computer is "larger than life" and that therefore we should automatically accept all the subsequent descriptions of how the computer can instantly simulate the entire universe and then some.

The reader is not supposed to believe quantum computers actually work like that. The computer is just a storytelling device, no more, no less.

Certainly the hyperbole is part of the story. And again, let me say I think its fun fiction.

However, I still have strong regrets that the author choose to stick the label "quantum" on it just to make it powerful/magical.

Why not call it a massively-interconnected, nano-organic cellular automata computer instead? Sure, it looses its literary flair, but quantum mechanics and computing is already so rarely understood in the public world, I hate to see fiction encouraging a deterministic model.

  I hate to see fiction encouraging a deterministic model.

I know I may get downvoted for this "me-too" comment, but just wanted to let you know that I was very happy to see both of your comments, as I share your sentiment exactly. This entire story is impossible, but many readers, not knowing much about QM might walk away thinking it's "plausible" due to their ignorance and the way the story is presented. Which isn't to say that's a bad thing on its own, but then they walk up to me and badger me with this bullshit... :-p

  I hate to see fiction encouraging a deterministic model.

I love to see fiction encouraging a deterministic model.

> Why not call it a massively-interconnected, nano-organic cellular automata computer instead?

That would be unrealistic, absurd, and impossible. How are you going to get an infinite amount of computation in finite time with a cellular automaton or a computer made out of discrete components? The only chance of realistic technobabble is quantum effects. That way, you can pull all sorts of mumbo jumbo like "doing infinitely many things in parallel" or "teleporting the results of computation across space without violating causality" or "expressing the future of a simulation in the binary expansion of real number." And the story simply wouldn't work without a deterministic universe.

P.S. I'm not the author.

If you go down the route of http://www.simulation-argument.com/faq.html then the computer is very important, since without one, case 2 dominates case 3 (the interesting one described in the story).

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