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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)

#151

Post by seanmcdirmid »

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…

Go with one of the more complex configurations in conway's game of life. Imagine the little squares gaining sentinence and discovering they are merely parts of a game of life simulation. A bit absurd.

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

#152

Post by SiddarthaBuddha »

comicjk wrote: post #86
Vraxx wrote: post #80

Earlier quoted context omitted.

I see the distinction you're making (I think), but I still don't see how that invalidates GP's analogy. Surely "running" a wavefunction is computationally cheaper than re-evaluating the particle's characteristics at every universal frame. Perhaps it's not so much about our own "watching" but rather "do not calculate when irrelevant". My own analogy might be an online map frame like google maps, where tiles outside th…

The particle's characteristics ARE the wavefunction - or to say it another way, the wavefunction is the only real characteristic a particle has. When I run a quantum mechanics simulation at work, I might afterwards calculate the particle positions or some other classical characteristic of the system. But I need those characteristics only because I'm trying to get a classical model of the system. The system itself, wh…

Is it possible that the calculations you are performing afterwards are what is causing the waveform interactions to have definitive results? In other words, could the waveform interactions cause the waveforms to become coupled and cause the entire system to exist in a superposition until such time as a classical measurement is made?

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

#153

Post by threepipeproblm »

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…

Yes, but in practice no one wants to go to a backup. So the simulators will try just deleting or messing with the aware person, creating Matrix-like glitches.

At least, that's the scenario depicted in the 1973 movie, World on a Wire. http://www.imdb.com/title/tt0070904/

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

#154

Post by logicallee »

SiddarthaBuddha wrote: post #149
logicallee wrote: post #147

Earlier quoted context omitted.

I disagree with you that: >and can impinge upon the simulations at any time A simulation could just be some states. Consider the rule, double and subtract one to get to the next world-state, over the integers, and start the world with the state 1. So the next state is 1. The one after is also 1. The one after is also 1. The universe is stuck in a static state. As I, you, or a Python script is modeling this universe,…

> this is 100.000% absolutely necessarily true and not open to debate That sounds completely absurd to me given that we can't even agree on a definition for consciousness.

It doesn't matter if you agree. Some of the world's 7 billion people likely believe that minds are like souls in a parallel ethereal plane and they could be severed, float around for a while, be attached to some other person and so forth. Regardless of whether anyone believes that it is just not true and conscienceness is an emergent propery of the person having it, and it doesn't really matter whether you or anyone else sees it that way.

It doesn't matter what you think conscienceness is or whether there is agreement on it. (Sorry if this is harsh.)

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

#155

Post by MichaelBurge »

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…

How do you explain that some algorithms are provably faster on quantum computers than classical computers, if quantum is merely an optimization?

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

#156

Post by to3m »

yodon wrote: post #103
komali2 wrote: post #67

Earlier quoted context omitted.

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.

Certainly, but the idea that some hyper intelligent entity would develop the tech to build a universe-scale finite element simulator without groking anti-aliasing along the way is simply absurd. Bresenham's algorithm is a big deal because it's essentially the first thing everyone needs to invent when they start trying to render continuous processes on a discrete grid.

Bresenham's algorithm draws aliased lines.

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

#157

Post by qubex »

3pt14159 wrote: post #145
jackcosgrove wrote: post #144

Earlier quoted context omitted.

If you can recurse infinitely, then there is no need to define reality as a simulation. A simulation implies some loss of fidelity relative to the layer hosting it. If you continue this infinitely eventually you end up with a completely entropic layer. Maybe there is a discontinuity and this entropic layer crystallizes into a highly ordered "base reality". I don't know how this innermost, entropic layer can contain t…

I disagree. A simulation has meaning even if there is not a base reality. A simulation is alterable in a way that a physicalists reality is not. For example by it's parent can slow it down, or alter physical constants.

A “slowing down” of a simulation would only be perceptible to those observing from without, not those who are observing from within, whose perceptive processes would be slowed in synchrony with the processes they are perceiving.

There's no reason to presume the simulation proceeds at a constant rate as measured from the outside world either: “render times” may vary with the complexity and fidelity required — for example when we innards fire up the LHC, a huge bump in resolution might be required. When we innards venture onto the moon, a whole new world has to be mapped in and professing speed might drop accordingly.

What the original poster is saying is that insofar as we do not know what the base reality is, there is no reason to argue that our reality is a lower-fidelity instantiation of it: we might as well be a flawless emulation of something totally orthogonal to the base reality.

Furthermore for obvious reasons computation cannot endlessly recurs endlessly and somehow forms into a loop: somewhere the arithmetic actually has to be performed.

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

#158

Post by SiddarthaBuddha »

logicallee wrote: post #154
SiddarthaBuddha wrote: post #149

Earlier quoted context omitted.

> this is 100.000% absolutely necessarily true and not open to debate That sounds completely absurd to me given that we can't even agree on a definition for consciousness.

It doesn't matter if you agree. Some of the world's 7 billion people likely believe that minds are like souls in a parallel ethereal plane and they could be severed, float around for a while, be attached to some other person and so forth. Regardless of whether anyone believes that it is just not true and conscienceness is an emergent propery of the person having it, and it doesn't really matter whether you or anyone…

How can you be so confident? You have no proof of this (or at least have not demonstrated it) and are simply going on faith which is exactly what someone who says that consciousness comes from the soul is doing.

And even if consciousness is an emergent property of the structure of the brain, how could we have a simulated brain report that it is experiencing consciousness when we cant define what it is in the first place?

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

#159

Post by breatheoften »

logicallee wrote: post #147
jackcosgrove wrote: post #107

Even if we live inside a simulation inside a simulation inside a simulation, ultimately there is a base reality that influences the design of the simulations contained within it, and can impinge upon the simulations at any time. Infinite regression doesn't work here - using the term "simulation" implies some special pleading when moving from the outermost simulation to the base reality. If you want to regress forever…

I disagree with you that: >and can impinge upon the simulations at any time A simulation could just be some states. Consider the rule, double and subtract one to get to the next world-state, over the integers, and start the world with the state 1. So the next state is 1. The one after is also 1. The one after is also 1. The universe is stuck in a static state. As I, you, or a Python script is modeling this universe,…

Reminds me of a short story called Luminous by Greg Egan. In that story the universe is a declarative system that does have a non-pseudo random component to it -- with actual reality being an emergent phenomenon between this declarative model and the entities within exploring that model by causing the universe to imbue the mathematical objects implied by the universe with specific reality by actually computing them, in so doing "expanding" the size of the universe and introducing new effects from this expansion into the evolution of the system ... in the story it turns out there are multiple actors active at the edge of defining the universe -- and their actions can actually influence the ability of other actors to continue in their participation in the universe creation process ...

Edit: my attempt to elaborate on the idea from the story ... I don't know if I can summarize the concept that well -- I think the framing within the story for the plot is something along the lines of: 1. Mathematical truth exists 2. There is an existential difference between a mathematical truth and a specific occurrence of the "pattern" described by that truth within the physical material of the universe.

I think the eli5 example in the story is based on the integers. You have the integers which are infinite, and you have an instantiated version of some number n if you have an occurrence of n things in nature. The reality of n is fundamentally different if you are in A universe with "n things" vs one with only m things mI think that's the motivation for the concept -- and in the story a researcher sets off to find scenarios where the universe had not yet "instantiated" one of the "laws" that could be derived from mathematical reality -- and ends up finding out that there is more than one possible way for the laws of "reality" to expand ... -- with different implications on what laws might be discovered in the future ...

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

#160

Post by zardo »

SiddarthaBuddha wrote: post #158
logicallee wrote: post #154

Earlier quoted context omitted.

It doesn't matter if you agree. Some of the world's 7 billion people likely believe that minds are like souls in a parallel ethereal plane and they could be severed, float around for a while, be attached to some other person and so forth. Regardless of whether anyone believes that it is just not true and conscienceness is an emergent propery of the person having it, and it doesn't really matter whether you or anyone…

How can you be so confident? You have no proof of this (or at least have not demonstrated it) and are simply going on faith which is exactly what someone who says that consciousness comes from the soul is doing. And even if consciousness is an emergent property of the structure of the brain, how could we have a simulated brain report that it is experiencing consciousness when we cant define what it is in the first pl…

We would necessarily have a much better understanding of brains and consciousness if we were able to build a working brain simulation.
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