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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)

#111

Post by mcherm »

Nadya wrote: post #73
ajuc wrote: post #57

Earlier quoted context omitted.

The difference is mathematical, not physical, so it should still hold.

The mathematics depend heavily on physics. If physics outside of our universe differ - the math wouldn't add up. I can make 2 + 2 = 5 in a simulation. That doesn't mean 2 + 2 = 5 outside of the simulation.

> The mathematics depend heavily on physics.

I do not believe that to be true. While physics is heavily dependent on math, the reverse is not true.

> I can make 2 + 2 = 5 in a simulation.

No, I am fairly confident that you absolutely can not. You can make a simulation where putting 2 oranges in a box and adding two more oranges results in 5 oranges in the box (rather like putting together certain nucleons together into a nucleus results in a mass different than the sum of their individual masses). But in that simulation it would be a peculiar property of oranges, not a property of mathematics -- just as we don't claim addition is invalidated by the behavior of nucleon masses.

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

#112

Post by mcbits »

ajuc wrote: post #93
aswanson wrote: post #91

Earlier quoted context omitted.

Sure he can. He can overload the "=" or "+" operator and make them do whatever he wants in that domain. Taking it further, what if rules and logic, and by extension, math as we know it, is just a construct that is not applicable in the "real" universe. What if, in that "real" space, 7+7=5, or mathematical operations are not possible. What if causality and time dont exist?

You can change symbols all you want, but when life appears in your simulation they won't care. If they put 2 items and then another 2 items, and 4 items are there - for all they care 2+2=4. And if sometimes its 5 - they will do what we did with relativity when it turned out velocities doesn't add up like they "should". We haven't changed addition - we changed the equations used in physics. I guess you could hand-made…

If you put 2 male mice in a box with 2 female mice and wait a while, you may find 5 or more mice in the box. Or if you put 2 clouds in a box and later put 2 clouds in the box, you probably won't find 4 or 5 clouds in the box.

The act of putting things in boxes (after first perceiving and classifying them as discrete entities) and the abstract notion of addition are only as related as you need them to be for a given purpose.

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

#113

Post by jblow »

aswanson wrote: post #31
4ad wrote: post #22

Earlier quoted context omitted.

> 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.

Who's to say "real" computing, or "reality" at all, has to adhere to the laws we observe within the simulation? That's like Luigi in Super Mario Brothers saying you can't kick a turtle into a brick in the our world and not expect a gold coin to pop up in front of our faces.

I wish most of the people who talk about the Simulation Argument understood this.

There is not even a reason to believe that the "outer universe" has such things as space and time or information as we know it, and no way to know what a "computation" might comprise in such a situation.

Maybe the situation is not that pessimal, and an outer universe is much like ours, but to prefer that believe one would need evidence, of which we have none.

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

#114

Post by inimino »

jblow wrote: post #113
aswanson wrote: post #31

Earlier quoted context omitted.

Who's to say "real" computing, or "reality" at all, has to adhere to the laws we observe within the simulation? That's like Luigi in Super Mario Brothers saying you can't kick a turtle into a brick in the our world and not expect a gold coin to pop up in front of our faces.

I wish most of the people who talk about the Simulation Argument understood this. There is not even a reason to believe that the "outer universe" has such things as space and time or information as we know it , and no way to know what a "computation" might comprise in such a situation. Maybe the situation is not that pessimal, and an outer universe is much like ours, but to prefer that believe one would need evidence…

The range of possible universes is much more broad than we can imagine. Even so, some people have imagined much further than most, through practice or some natural tendency. Our intuitions developed to fit the universe we are in. Getting beyond that is difficult and not many even try.

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

#115

Post by inimino »

codesnik wrote: post #49

I'm really surprised (every time!) when someone talks about conscience or discoveries or whatever so human-centric and local and unimportant in the cosmic scale while talking about simulations. If it's simulation, it certainly isn't made because of us.

We are on the only planet we know about with life on it, so it is fairly easy to assume this is the most interesting place in the universe. Whether that's rational or not is another question, but it doesn't seem surprising.

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

#116

Post by botw »

The other day I saw a post on social media that how he explained spaces from 0-dimension to 10-dimention in simple drawings. At the end, he claims that 10-dimentional space is just a dot, and there is no higher dimensional space more than 10-dimention any more. And he justifies his claims based on the string theory. At that time immediately I thought about the billions of parameter space in deep neural network and fractal spaces such as Mandelbrot Set. How could one simulate the universe based on only 3D space-time lattice?

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

#117

Post by danbruc »

In my opinion this seems all pretty pointless. To be able to differentiate between a simulation and reality you have to know at least how one of those works in quite some detail. What if we discover floating point rounding errors in the laws of physics we observe? Who is to say that this is not a feature of reality? What if it is the other way round, what if we live in a simulation with laws of physics made out of real real or complex numbers but the reality outside of our simulation has laws of physics behaving like floating point numbers? It seems pretty impossible to ever figure out what reality or a simulation must look like so that we can determine what surrounds us. Maybe there is some incredible self-consistency law at the bottom of reality, forcing reality to be what it is because there is one and only one way reality can be. But besides something like that?

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

#118

Post by nefitty »

zizzles wrote: post #60

Should we perhaps hypothesize the motive of this simulation, if any? Death seems to be a very important focal point: All living organisms are condemned to their aging bodies, eventually begin decaying, then die. Death of the universe is also inevitable, "Heat Death". Then there are other existential issues our feeble brains have to deal with. Then of course, our Earth is replete with suffering around every corner. Pe…

Entropy could just be an inevitable factor in this simulation. As the simulation steps forward in time, with the rules set forth at the beginning, these different emergent properties of the universe begin sprouting. There may not be a motive at all for this or an other simulation, besides gathering data on the effects of different rulesets.

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

#119

Post by knieveltech »

45h34jh53k4j wrote: post #78
drakonandor wrote: post #56

Earlier quoted context omitted.

This is a really odd website for you to be on if you're questioning the appeal of intellectual curiosity.

burned! :-X I guess my issue is not faulting intellectual curiosity in general, but directed curiosity at something with so many existentially negative results.

Response 1: because ignoring things with potentially existentially negative results is the functional equivalent of sticking your fingers in your ears and shouting 'LA LA LA LA LA'. Response 2: many (most?) people have a tiny little voice in the back of their head that whispers "Jump! Jump!" whenever they're close to the edge of a roof, cliff top, etc.

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

#120

Post by aswanson »

mcherm wrote: post #111
Nadya wrote: post #73

Earlier quoted context omitted.

The mathematics depend heavily on physics. If physics outside of our universe differ - the math wouldn't add up. I can make 2 + 2 = 5 in a simulation. That doesn't mean 2 + 2 = 5 outside of the simulation.

> The mathematics depend heavily on physics. I do not believe that to be true. While physics is heavily dependent on math, the reverse is not true. > I can make 2 + 2 = 5 in a simulation. No, I am fairly confident that you absolutely can not. You can make a simulation where putting 2 oranges in a box and adding two more oranges results in 5 oranges in the box (rather like putting together certain nucleons together in…

Suppose a "reality" where every observation of "addition" yielded unpredictable results. Would your confidence still be warranted?
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