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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)

#121

Post by eastindex »

aswanson wrote: post #106
ajuc wrote: post #93

Earlier quoted context omitted.

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…

The point I was trying to raise, though, is what if the concept of "adding two things" has no basis in the "real reality". I know its hard to grasp...but imagine a reality where there is no "+" or "-" operation.

But "+" and "-" operations are inherently time bound.

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

#122

Post by nefitty »

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.

You could argue this about so many scientific endeavors: the heliocentric model, the search for extraterrestrial life, climate change, the theory of evolution, the big bang theory, etc. These all had serious existential effects on society but society has also benefited greatly in other ways. I don't see why clarifying the nature of reality with regards to simulations would be any different.

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

#123

Post by pmontra »

danbruc wrote: post #117

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 re…

Not so pointless. Think that one of the NPC in a computer game gets intelligent. It could learn how to trigger bugs or cheats in the game or features thought only for the player. Examples: crash the game, which hopefully restarts from the last save. Get where no NPC was supposed to be, only players, and get teleported somewhere else. Trigger a stack overflow and perform actions in the host, maybe changing the programming of the game or the data in the save files.

In our case it could be the way to FTL. Did any Sci-fi author considered that yet?

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

#124

Post by aswanson »

eastindex wrote: post #121
aswanson wrote: post #106

Earlier quoted context omitted.

The point I was trying to raise, though, is what if the concept of "adding two things" has no basis in the "real reality". I know its hard to grasp...but imagine a reality where there is no "+" or "-" operation.

But "+" and "-" operations are inherently time bound.

why? and what is "time?"

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

#125

Post by Smaug123 »

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…

Sorry, I think I might be misunderstanding you. By "We live in the base reality", do you mean "Even if we live in a simulation, the simulation itself is hosted somewhere; following back the chain, eventually you reach the base reality. Therefore in the same sense as one should say that Microsoft Word runs/exists in our real world, one should say that (even if we're simulated) we exist in the base reality"?

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

#126

Post by Smaug123 »

pmontra wrote: post #123
danbruc wrote: post #117

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 re…

Not so pointless. Think that one of the NPC in a computer game gets intelligent. It could learn how to trigger bugs or cheats in the game or features thought only for the player. Examples: crash the game, which hopefully restarts from the last save. Get where no NPC was supposed to be, only players, and get teleported somewhere else. Trigger a stack overflow and perform actions in the host, maybe changing the program…

"hopefully restarts from last save" - that's an awfully big gamble to take when the stakes are all of human existence.

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

#127

Post by dasil003 »

aswanson wrote: post #120
mcherm wrote: post #111

Earlier quoted context omitted.

> 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?

There's no direct observation of addition, it's just a symbolic construct to model something we observe. I suppose a reality where such a model never made sense is possible, but it would be a very foreign environment that is completely outside the scope of our intuitive understanding. If it made sense only for a subset of the cases it does in our current understanding, then that would be the context in which it was discovered/understood.

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

#128

Post by monktastic1 »

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…

Various eastern philosophies have a somewhat different solution to this whole problem.

Consciousness -- as in the sheer fact of experience -- is itself the base "reality," out of which everything is made. If you examine everything you're calling "the universe," all you will ever discover is sights, sounds, thoughts about sights and sounds, belief (or certainty) that those sights and sounds are caused by something external, etc. What are all of those made of? Consciousness, of course.

In this reality, "brains" are the entities that consciousness has dreamed up to demonstrate correlations with conscious properties. In our reality, we therefore say that "the brain causes consciousness."

If you investigate your experience closely, you'll discover that the epiphanies "I exist," "I am conscious," "I am alive", "a world exists" all point to the same ineffable "miracle" of existence, the one "substance" of which all realities are made.

Upon hearing this, perhaps the mind thinks "just as there are realities that exist without time and space, why can't there be some without consciousness?" There's a very interesting answer to that question, but it won't come in the form of thoughts.

Of course, there's no reason to believe any of that. On the other hand, as the Buddha said, don't believe me....

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

#129

Post by akvadrako »

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…

You imply twice in your post that you assume there is a base reality, but why?

I could argue it makes just as much sense that every layer is simulated by the layer "above". That could continue ad infinitum or perhaps create a cycle, so eventually it's simulating itself. These may be what we refer to as simulations, like what's running on my PC, or some kind of emergent behavior. Either case seems to work.

It's natural to define the universe / all of reality / all layers as that which is self-defining, which is hard to describe without circular reasoning.

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

#130

Post by akvadrako »

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…

That seems like a major roadblock, but hackers could imagine ways around it. Let's make it easier by assuming the creator can only store so many backups before running out of resources. That seems fair if simulations are anything like what we have now and restarting from scratch is unfeasible, perhaps due to lost input data or deadlines.

Then one approach would be to silently and irreversibly corrupt the simulation in a way that will become noticeable. Perhaps you fill every document with secret messages that require AI as smart as the sims to detect and is only revealed years in the future.

By the time it is noticed it's too late and removing all those messages will require more resources than the simulation itself. Trying to catch them on demand will require understanding how the brains of the sims work internally, which may be unfeasible.

That idea is probably preventable, but I'm sure there are exploitable and non-reversible security holes in any imperfect simulation.

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