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Comment by JohnLeTigre | Hacker News Reader

There is no such thing as a perfect computer that runs eternally or that can simulate something with an infinite degree of precision.

If we lived in a computer simulation, we would have noticed unusual meta-physical glitches as discrepancies within the 'order of things'.

For example, if the simulator used floating points, we would actually notice that numbers end up loosing precision after a certain amount of decimal points. We would probably have tons of theories about that and wonder why the metaphysical rules that are involved in counting suddenly change at specific precisions. etc.

no glitches = no simulation

There are many more problems with this premise but to me, these types of questions are a waste of intellectual energy so I'll leave it at that I guess, have fun.

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It is well known how to represent arbitrary-precision decimal numbers in a computer, so I don't get your point about precision of counting. Furthermore, the fact that the simulating computer stores the state of our atoms in some kind of floating point doesn't mean that when we think about the concept of numbers, we are limited to floating point. The abstraction capability of the human mind means that we can think about numbers that are larger, or more precise, than any physical magnitude in the universe. It is easy to write a number way larger than the number of elementary particles in the universe, and we don't make the universe overflow when we do that.

In fact, we know that there are limits in our world to how small a physical magnitude can be - Planck's time, Planck's length, etc. This seems quite coherent with a computer with finite memory simulating our world.

If the guys creating the simulation have enough resources and skill (superhuman beings from an external universe wouldn't necessarily make bugs when coding) I don't see why we would notice any glitch. Even more so when the part of the universe that we perceive is relatively tiny, and anyway the set of things that we can and cannot notice may be determined by the program itself.

But the simulation doesn't have to be perfect. It doesn't have to be complete. Maybe only you and your friends are actually being simulated, and everything else is just a partial stub. Maybe only the relevant parts are rendered.

I actually read Nick Bostrum's original paper and it's a pretty interesting read. Basically it looks at the long tail end of things. When you predict things waaay into the future, you tend to gain accuracy for macro predictions.

For example: our sun will most likely run out of energy and die out one day. The plate border in East Africa will most likely break apart at some point causing that continent to split.

The big one: humanity will one day go extinct. ... or...we'll expand to Mars and other parts of the solar system and thrive for millions of years. There are other options of course (we get blown back to the stone age, some humans survive and technology has to restart from a few thousand years ago...repeatedly...until we either leave this planet or go extinct).

If our machine understanding continues to grow, we should be able to eventually make machines that can simulate parts of the world we're in. So either we've already done that (some other we), and we (you and I we) are the products of their simulation ... or we'll go extinct one day.

...or simulating this world, perfectly or imperfectly, isn't possibly at all. ... and we'll go extinct one day.

>Maybe only you and your friends are actually being simulated

Why waste so much resources, when it can be just You being simulated?

Maybe the glitches are too small for us to detect. Perhaps lesser than the Planck constant. Maybe most of them have been debugged away.

It is impossible to infer the capabilities of the "host" machine, being inside the simulation.

My mind can't also infer why beings advanced enough to simulate our universe would stick with something as primitive as IEEE floating point. Surely their machines would be fine with arbitrary precision?

Are you referring to the Heisenberg Uncertainty Principle? Of course, that still doesn't mean we're necessarily in a simulation!

"...unusual meta-physical glitches as discrepancies within the 'order of things'."

Like... dark matter?

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