Can someone summarise the paper? Seems to complex for a lay-man. For example, what is Lattice QCD?
Constraints on the Universe as a Numerical Simulation (2012)
141–150 of 178 posts
Re: Constraints on the Universe as a Numerical Simulation (2012)
#142Earlier quoted context omitted.
> 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. Keep in mind that if you wanted to create an operating system, you can ensure that there are no kernel exploits. If there is some kernel exploit, you can simply patch t…
There are Operating systems without Kernel exploits, they are simply less efficient than modern OS's.
Who says efficiency was not a concern when developing the universe? Otherwise the creators would not have included limitations like finite light speed or Heisenberg indeterminacy principle to reduce computation time. :-)
Re: Constraints on the Universe as a Numerical Simulation (2012)
#143Even 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"?
Correct.
Re: Constraints on the Universe as a Numerical Simulation (2012)
#144Even 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 natura…
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 the outermost, ordered layer. I think "simulation" is a bad term since it implies a monotonic loss of fidelity.
A simulation only has meaning if there is a base reality. Otherwise there are only layers of reality.
Re: Constraints on the Universe as a Numerical Simulation (2012)
#145Earlier quoted context omitted.
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 natura…
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.
Re: Constraints on the Universe as a Numerical Simulation (2012)
#146Earlier quoted context omitted.
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…
But how would that NPC know that it is in a game? What if we figured out how to do teleportation or time travel? How would you determine whether that is a feature of reality or whether we discovered a bug in a simulation?
Gut feeling: it can't know. But the simulation in some way is part of reality and maybe that's why it couldn't be known.
I guess there has been plenty of philosophical research on this subject.
Re: Constraints on the Universe as a Numerical Simulation (2012)
#147Even 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, where does the outside universe "impinge" on it?
Then let's do a different universe, starting at 2. Then the next state is 3, the state afrer is 5, the state after is 9, and so forth.
As you do this universe in your head, where does the outside universe "impinge" on it?
There is a problem, however. All future states are well-defined in the universe I've given even if nobody in our universe or any other is calculating them.
It is trivially obvious that the human mind is an emergent property of its neural firings (of the brain), and that replacing some part of it with a black box that interacted with the rest would leave it with the same emergent properties, even if this black box were modeling in a different medium.
The question is, if you can model the whole thing over a well-defined program that did not require non pseudorandom entropy, then it would be similar (just start with more complex data than 1 or 2, and more complicated rules than double and subtract one) - so in order for these states to exist, would anyone have to actually calculate it, or is it enough for these states to be mathematically defined?
What I am saying is that it is a statistical certainty that within a thousand years we can create a deterministic model of a brain in a VR, where the brain reports consciousness. (this is 100.000% absolutely necessarily true and not open to debate. The brain is a couple of pounds of stufd, with just a few hundred billion neurons or fewer - I bet we could practically have the hardware to model one today.)
Does this mean that that model already exists? (before anyone chose to calculate it)?
This is similar to asking whether the quintillionth prime exists. Yes, of course it exists.
Really? Even if nobody calculates it? Then what is to say that we might not exist without anyone calculating us?
Perhaps the states of the universe, like the quintillionth prime, exist without anyone calculating it. Perhaps there is no underlying reality at all, just as there is not an underlying reality in which the quintillionth prime is embedded.
Re: Constraints on the Universe as a Numerical Simulation (2012)
#148Earlier 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?
Addition is defined in such a way that the universe it's performed in doesn't matter (in fact, no universe is required at all), which is true for most if not all of formal mathematics. See set theory 101 for the very beginning on how's that possible.
Re: Constraints on the Universe as a Numerical Simulation (2012)
#149Even 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,…
> 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.
Re: Constraints on the Universe as a Numerical Simulation (2012)
#150Earlier quoted context omitted.
But how would that NPC know that it is in a game? What if we figured out how to do teleportation or time travel? How would you determine whether that is a feature of reality or whether we discovered a bug in a simulation?
Gut feeling: it can't know. But the simulation in some way is part of reality and maybe that's why it couldn't be known. I guess there has been plenty of philosophical research on this subject.
But exactly that was my point - unless you know what either reality or a simulation really looks like, you can not look around and draw conclusions whether we live in reality or a simulation. People trying to do this make the assumptions that a simulation would have properties similar to simulations we perform and that reality would have properties similar to the laws of physics as we know them, but neither assumption seems really justified.