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Constraints on the Universe as a Numerical Simulation (2012)

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Re: Constraints on the Universe as a Numerical Simulation (2012)

#61

Post by niftich »

3chelon wrote: post #54

On a semi-serious note, I've always had this nagging feeling ever since I first heard of Planck time and Planck length. Why would there be a lower limit to the resolution of the universe, unless there was something spooky going on? (I know they're just theoretical, but...)

I'm not a physicist, so I'm speaking as 100% layman, but I can better accept a fixed-resolution universe, where forces have a certain magnitude and beyond them (in either direction, smaller or larger) matter doesn't behave in productive ways.

For a long time, we thought atoms were these building blocks; now we think it's quarks; the Standard Model does a pretty good job at relating all observed phenomena to each other, except for, you know, gravitation, and that pesky observed-but-unaccounted-for thing we deemed 'dark matter'.

A few things about the Standard Model make my head hurt, but the idea of a fractal universe that is infinitely scalable up and down and assumptions about spacetime and forces still hold the same way is truly mindbending that I don't know how to reason around it. So perhaps conversely, can we flip the question and ask, why wouldn't the universe have a finite resolution in terms of matter actually existing and behaving like we know and love?

Re: Constraints on the Universe as a Numerical Simulation (2012)

#62

Post by ajuc »

45h34jh53k4j wrote: post #29

Sigh. Why would you dedicate your life to proving this? You will either find you cannot prove it, in which case you have wasted your entire life on falsehood, or you prove it true in which you undo your dilute your existence and everyone you have ever known and loved. Kinda like religion I guess...

I dont understand why 1 more llayer of abstraction makes a difference. You are a software running on neurons interacting with simulation of outer world.

Re: Constraints on the Universe as a Numerical Simulation (2012)

#63

Post by CoryG89 »

mentos wrote: post #21

What is interesting is if we are the result of an unfathomable number of transistor gates, the consciousness that arises from it would never be able to understand the 'platform' (hardware) that it sits on.. would it? The idea being that you are creating a new dimension that cannot see the dimension that gave rise to it. I feel like no matter what we are in a 'simulation' where another dimension gave rise to ours whet…

Is this really true? What about a self-aware AI? I can imagine an AI that resides on a chip and developed consciousness could conceivably control a camera/robot in the real world and literally inspect and even reverse engineer or repair/improve itself or the hardware it runs on.

Re: Constraints on the Universe as a Numerical Simulation (2012)

#64

Post by pmoriarty »

teraflop wrote: post #41
smrtinsert wrote: post #7

What sort of moral issues result from creating a simulation universe that gives rise to sentient beings? I feel creeped out and reminded of Source Code with Jake Gyllenhaal for some reason.

Greg Egan has written a (slightly ham-fisted, but still interesting) short story about that question: http://ttapress.com/553/crystal-nights-by-greg-egan/ The author has commented that he regrets having overlooked the moral implications of simulated life in his previous works (see e.g. http://gregegan.customer.netspace.net.au/PERMUTATION/FAQ/FAQ... , which contains spoilers for Permutation City ) so I wouldn't be sur…

Also highly recommended along these lines is Stanislaw Lem's Cyberiad (published in 1965):

https://www.amazon.com/Cyberiad-Stanislaw-Lem/dp/0156027593

It touches thoughtfully and humorously on: AI, simulations, robotics, ethical and moral questions regarding artificial life, among many other interesting topics. It's one of the funniest and greatest science fiction books I've ever read.

Re: Constraints on the Universe as a Numerical Simulation (2012)

#65

Post by komali2 »

4ad wrote: post #22
astrodust wrote: post #16

Keep in mind that if you wanted to create a simulated universe you can ensure nobody ever finds out. If someone does find out, you can simply fix the problem and revert to a point in time just before the data leading to the discovery was captured. Speaking academically, you might be playing with fire if you probe the outer limits of the universe and we are in a simulation run by some entity concerned with keeping tha…

> you can simply fix the problem and revert to a point in time just before the data leading to the discovery was captured. Only with classical computers, not quantum computers.

How does that matter?

Re: Constraints on the Universe as a Numerical Simulation (2012)

#66

Post by mentos »

tonmoy wrote: post #38
mentos wrote: post #21

What is interesting is if we are the result of an unfathomable number of transistor gates, the consciousness that arises from it would never be able to understand the 'platform' (hardware) that it sits on.. would it? The idea being that you are creating a new dimension that cannot see the dimension that gave rise to it. I feel like no matter what we are in a 'simulation' where another dimension gave rise to ours whet…

Nobody said the simulation is being done with transistors. Even if it was why wouldn't it be possible? I don't see any constraints. One day humans will fully understand neurons. One day we will make an AI using transistors who will be able to "understand" transistors

I meant it more in an abstract sense. They don't have to be silicon they could be enormous metal planets and moons..

Re: Constraints on the Universe as a Numerical Simulation (2012)

#67

Post by komali2 »

yodon wrote: post #50
aq3cn wrote: post #2

For those, who want to read it in lay man's language, they can go through following articles: https://www.technologyreview.com/s/429561/the-measurement-th... http://www.huffingtonpost.in/entry/physicists-may-have-evide...

The tech review summary seems to be saying this super intelligent universe-simulating computer builder doesn't know about Bresenham's line drawing algorithm [0] and as a result it can only walk high energy particles along a limited number of paths. [0] https://en.m.wikipedia.org/wiki/Bresenham%27s_line_algorithm

Possibly? I can see why one would want to assume that an entity that can simulate a universe would be able to know more than the collective ability of that simulation, but on the other hand, we simulate things and learn unexpected results from our simulations. I think it's entirely feasible that a simulation can generate more knowledge, or different knowledge, than exists outside the simulation.

Re: Constraints on the Universe as a Numerical Simulation (2012)

#69

Post by comicjk »

lossolo wrote: post #27

I would be surprised if we are not living in simulation. Look at superposition and function collapse in quantum physics, it's equivalent to what we are doing in games today = do not render if player is not watching, save resources. Think about it, look for example at GTA V, what we can achieve today and think about how world looked like 100 years ago. I imagine that in 1000 years from now, simulating world similar to…

This is a common misconception, but superposition has nothing to do with "do not render if the player is not watching." As far as we know, every particle in the universe is interacting with every other (with a light speed delay) and thus "measuring" it (modifying and responding to its wavefunction) at all times. In the two-slit experiment, for example, the wavefunction of a particle moving through a slit interacts with the wavefunction of the particle used to detect it, causing both wavefunctions to be more narrowly distributed in the space around the slit. But before or after this interaction, the whole wavefunction still needs to be simulated to produce the effects we see experimentally. The wavefunction itself is the real thing being simulated, and it's always "running."

You may be right that it will become easier to simulate worlds like ours, but it will require innovations that make a quantum computer look like an etch-a-sketch. The universe is really big and really detailed.

Re: Constraints on the Universe as a Numerical Simulation (2012)

#70

Post by komali2 »

lossolo wrote: post #27

I would be surprised if we are not living in simulation. Look at superposition and function collapse in quantum physics, it's equivalent to what we are doing in games today = do not render if player is not watching, save resources. Think about it, look for example at GTA V, what we can achieve today and think about how world looked like 100 years ago. I imagine that in 1000 years from now, simulating world similar to…

I'm not sure I buy into that, because we haven't been able to draw a strict line between what a "player" and "npc" would potentially be.
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