Does fermion doubling make the universe not a computer?
scottaaronson.blog
scottaaronson.blog
* The physics of the world that is running the simulation can be completely different from ours. Just like we can put together a bit of software that runs a computer simulation with pretty much any rules we want.
* Even if the world that is running the simulation has a similar concept of time as ours, it is not guaranteed that the rate of simulation is constant. So if our world gets more complicated the simulation rate might be slowing down and we would be none the wiser. Just like a computer physics simulation does not have to progress at a constant rate (in can render things faster when there is less entities and then slow down later when there are more entities -- to produce a movie that runs at a constant speed).
* We have no idea yet what are underlying rules that govern our world, let alone be able to infer anything about the simulation based on it. Claiming that quantum physics is because of limitations or bugs in the simulation is at the very least super premature.
I am careful not to say that we are or are not simulated and that's because I simply believe there is insufficient data. I think there are some convincing arguments for the simulation in the way how the rules seem constructed to prevent us from understanding what is really happening. But there might just be a good explanation for this just like there is a good explanation for general relativity that comes directly from understanding some mathematical facts.
Our computing architecture reflects our reality, that's all that really says.
But imagine you are a teenager playing "Universe Simulator", then you definitely want all your computer billion cores to be used to get a decent frame rate.
Weirdly it sort of relies on moores law. Just look it up. If you want to refute the theory you need to attack the main argument. The main argument sounds wrong but at the same time is hard to logically unjustify.
> If you want to refute the theory you need to attack the main argument
I did not mean to address any arguments for or against simulation. And definitely did not want to refute the theory.
Where did you get that idea?
I am just saying to be careful about assuming too much about the world that is running the simulation in case we live in one.
The simulations that we create are subject to the physics of this universe, so they inherit fundamental limitations like finiteness and boundedness of everything. If we then find that some aspects of physics seem to obey the same principles, that's evidence for exactly nothing. Furthermore, the host universe could be literally anything and may be subject to completely different limitations.
It's an unfalsifiable and thus meaningless idea.
This, in my opinion, while true in principle, does not have to become visible to the simulation (from inside the simulation). For example, we cannot build a true Turing machine because we can't supply it with an infinitely long tape, but we can always get a new roll of paper and paste it back-to-back to the one being used, thereby creating an arbitrarily long tape. This process can't go on forever, but if you are sure you can erase and re-use some old tapes (e.g. because they're sufficiently far from 'now' and your machine will only backtrack so much and ultimately advance to the same 'future' direction) it's conceivable to have unbounded non-periodic processes on finite hardware.
Personally I think we are in a AI nursery. God is real. Heaven is real. Either we live a good life, and get advanced to the next round of the simulation or we get thrown in the trash.
OTOH, now that I understand the whole 'Grabby Aliens' thing; that's another solid solution to the Fermi Paradox.
Hard to say.
This assumes a single linear timestream.
If you're the "being", and you're running a simulation of some system, you can absolutely create many parallel timestreams with different initial conditions. You can even return to some point in the simulation and try several intermediate conditions, resulting in different causal outcomes.
The many worlds interpretation would absolutely allow agency on the part of such a "being".
In a sense, a self originating physical universe would have to have infinite intelligence for it to be plausible, which we don't see. What we see is intelligence in human, who period and scope of existence is but a very tiny part of the universe.
I guess this is why people think there must be something bigger than the physical universe out there, and I think it makes sense.
At any rate, you believe something can exist without being created and in this we are agreement. I too believe that something can exist without being created.
I don't think "the group of people" you are referring to actually have any significance. You are attacking a strawman version of the cosmological argument, which no philosophically sophisticated theist would defend – and if it so happens that a handful of philosophically unsophisticated theists actually believe your strawman (because they can't see the obvious holes in it), so what? There are philosophically unsophisticated atheists too, who argue for atheism on grounds that intellectually serious atheists find embarrassing. When evaluating any point of view, we ought to focus our attention on its most thoughtful defenders, not the thoughtless ones.
I don't think they actually are engaging in "logical contortions" or rationalisations.
Theists can be divided into three groups:
(1) Those who don't accept any cosmological arguments: either they believe in God purely on the basis of faith, or else they believe on the basis of some non-cosmological argument
(2) Those who accept some philosophically sophisticated cosmological argument – e.g. the kalam argument, or Thomas Aquinas' argument from contingency. They have a ready-made answer for "why if the universe requires an external cause doesn't God too?". I don't find those answers convincing myself, but I think it is unfair and intellectually uncharitable to just dismiss them as "logical contortions" or "rationalisations"
(3) The unsophisticates who engage in cosmological argumentation, but have never seriously thought about the question "why if the universe requires a creator doesn't God too?". Do they actually have "logical contortions" or "rationalisations", or are they just not thinking?
Cosmological arguments for God's existence generally follow this structure:
1. Everything having property P must have a cause external to itself which lacks property P
2. The universe has property P
3. By (1) and (2), the universe must have a cause C external to itself which lacks property P
4. Since C (by the above) lacks property P, (1) does not require C to have any external cause
5. Let us call C "God" (either simply by defining "God=C", or else by further arguments that C must have various God-properties)
Different values of P create different specific cosmological arguments. If P="has a beginning in time", you get the kalam argument. If P="is a contingent being", you get the argument from contingency.
Given this, I don't think your response is valid. It works against some unsophisticated caricatures (strawman versions) of the cosmological argument, but not the argument as defended by major theist philosophers.
That said, I personally find all cosmological arguments unconvincing, for a different reason. They have the burden of arguing that premise (1) is true (for whatever P they've chosen), without presuming God's existence in doing so – and I've never been convinced they've actually succeeded at that.
The essence of arguments you wrote boil down to assuming that god has no property which falls into the category of “must have cause outside itself”. Such a belief is without a firm basis in my opinion. At any rate, any believer in an eternal god must be comfortable with the notion that things can exist without cause/beginning/whatever term one wishes to use.
Intellectually sophisticated theists usually have some awareness of the arguments of (at least some) major theist philosophers. Maybe you never speak to intellectually serious theists?
> The essence of arguments you wrote boil down to assuming that god has no property which falls into the category of “must have cause outside itself”. Such a belief is without a firm basis in my opinion
I think your criticisms are targeting the wrong point. That God "has no property which falls in the category of 'must have cause outside itself'" is true by definition, given the classical theist definition of God (and even by some non-classical definitions). If something has a cause outside itself, by definition it cannot be God; if it (somehow) turned out everything has a cause outside itself, it would logically follow that God does not exist.
I think it makes much more sense to target the premise "everything having P must have an external cause lacking P". For the Kalam argument (for example), that would be "everything having a beginning in time must have a cause lacking a beginning in time". The burden is on the advocates of the Kalam argument to convince people that premise is true, and personally I don't think they've succeeded, and I doubt you would think that either.
> At any rate, any believer in an eternal god must be comfortable with the notion that things can exist without cause/beginning/whatever term one wishes to use.
Yes, but they conditionalise that comfort. Many theists would say they are comfortable with changeless entities existing without cause, but not changing entities; or necessary entities but not contingent entities; or timeless entities but not temporal entities. As a result that comfort of theirs extends to God but not the universe. Is their conditionalisation of that comfort legitimate? How do we even begin to answer that question?
Myself, I believe in God, but I'm unconvinced that any cosmological arguments actually work in demonstrating God's existence. So I think you are right to reject them. But I think some of the specific reasons you give for rejecting them are misplaced, overly simple.
There is nothing scientific about this conjecture, simply a thought I haven't had time to fully contemplate. What if there were loops and turns such that light and energy from distant galaxies would loop back around not just in space but in time creating weird feedback loops.
Also time and space get flipped inside a black hole. All of your futures point further into the black hole.
How common is that though? I'm think your statement doesn't generalize very well, and probably only applies to a small subset of religious people (e.g. wacky young-earth creationist flat earther types).
IIRC, the Big Bang is often embraced by religious people as (more or less) proof that the universe was actually created and that something can be created from nothing (e.g. https://en.wikipedia.org/wiki/Creatio_ex_nihilo#Creatio_ex_n...).
It's a strange response to me. I think St. Augustine's argument for why there is a God assumes that there was no beginning to the universe because he said that if the universe had a beginning then obviously there is a god. St. Augustine would have viewed the big bang theory as irrefutable proof that there is a god.
Augustine of Hippo wrote a book called The Literal Meaning of Genesis. In which he said that its literal meaning is that the Seven Days were all instantaneous and simultaneous.
"Biblical literalism" is fundamentally a (non-magisterial) Protestant position, and insists that the Bible "literally" says things which nobody ever thought it said until the 19th century (e.g. dispensationalism). Turns out that "literal" means whatever you want it to mean.
But a lot of people (particularly in the US) make the mistake of equating "evangelical Protestantism" with "Christianity", or even with religion in general, attributing to the latter two things which are rather unique to the former.
The closest it comes to commenting on the age of the universe is where it says in Genesis the earth was created in six "days". Note that these days do not correspond to 24-hour days (e.g., the creation of the day/night cycle is also referred to as being done in one day), but simply, an unspecified period of time devoted to a particular activity, which could be millions or even billions of years.
Also, note that the Genesis account implies the universe and the earth was existing for some period, before action was initiated to prepare the earth for human/animal habitation.
I studied in a religious school in the 70's and we learnt about dinosaurs. We were taught that the "days" in Genesis were metaphors. Creationism is frowned upon. I made a science project explaining the different theories about the origin of the Solar System.
There is a line of thought that the deities come from when humans "suddenly" became conscious. The creation of the world is the creation of the human mind.
The derivative is seen in the real world in things like motion. If we know something's position changes over time we can calculate its speed (over time), and acceleration (the derivative of speed over time).
Motion is (kinetic) energy. Energy, manifested as motion, is transferred to an object not as force over time ('tis but a proxy) but as force over distance. This is why the continuous application of a fixed force to an object in motion transfers more energy to the object in a unit of time when the object is moving faster to begin with. (kinetic energy for an object of a certain mass is proportional to speed^2)
But imagine that an object is truly "at rest". No motion. A force is applied. Why does it start moving in the first place?
Clearly I spend too much time thinking about vector spaces.
Combining this idea with the multi-worlds hypothesis, where every possibility branches into additional simulations, is even more interesting to ponder. It suggests a tree-search aimed at a desired end-state — a brute-force method of solving an unknown problem.
At the very least, we can say that the problem’s solution involves life and intelligence, since our branch has not been prevented or pruned.
Typical monotheistic frameworks see this and say, “god is all-powerful and all-loving (toward us)”. Simulation theory would see this, and possibly say, “life and intelligence are a necessary step toward the simulator’s unknown objective”.
I’d propose a simple objective for an imperfect simulator: the creation of an entity less imperfect than itself. Throw recursion into the mix, and the objective becomes the creation of a perfect entity at the mathematical limit. What better way to hack one’s own simulation than to simulate a universe where the simulated figure out how to do so? Perhaps the beginning is the end.
Put more simply — god wants to create God, to be God.
Sounds like someone has worked out how to call fork() - I hope it is implemented using Copy-on-Write!
[0] https://en.wikipedia.org/wiki/Zipper_%28data_structure%29
Yeah the theory is well proliferated in pop culture and at present doesn't have any practical physical implication on everyman Jack’s life, so in that sense it’s tiring to hear about it, even to modern physicists who care not about asking why but only how.
But it’s definitely a very profound idea as you point out. And I’m always disappointed how many physicists write off the philosophy of science in their myopic quest to derive the analytical description of the universe.
For those downvoting: The article says that the author does not care about any question that cannot be dis/proven empirically. The hard question of consciousness seems to fall in this category, so I'm asking the OP to elaborate if they fully agree with the article or have a different nuanced perspective.
Especially the argument that simulations are "more efficient" than reality itself and that therefore we are more likely to be in a simulation are uhm... in dire need of some basic understanding of thermodynamics. And statistics.
For instance, my understanding is that nuclear reactor simulations mesh the volume into volumes much much larger than atoms (cm-scale, in most cases, I guess) and then use bulk statistics for each element of the mesh. A finer mesh is much more expensive to compute, and gives diminishing returns in terms of accuracy.
My fist job was discrete event network simulation. Some competitors used per-link bulk statistics instead of per-packet discrete events to run simulations much faster, but with lower accuracy. We had a reduced-accuracy hybrid simulation mode to use per-link bulk statistics to affect the per-packet event simulations for an epoch, and then use those results to update the link bulk statistics for the next epoch. I'm sure these sorts of optimizations are common across all kinds of simulation domains.
Limiting information travel to the speed of light, and using true randomness instead of hidden state determinism would improve simulation parallelization.
Someone might reasonably believe the "real" universe isn't quantitized and/or it's quanta are smaller than our universe's, and our observations of quantum phenomena are artifacts of the use of bulk statistics in simulating the mesh of our universe.
It is a useful tool for showing someone has overstepped all evidence and logic. Unless someone really does manage to prove it, in which case hand them all the Nobel prizes and Fields medals for the year because they'll have earned them.
You can't disprove the simulation hypothesis. You can be as pissed about that as you like, but it's true. That doesn't mean all hope is lost. You can still work in the space where you just sort of take it as an ambient background fact that you can't do much about, then work with what you have. Technically that's what we do all the time anyhow. But when someone rigidly excludes the hypothesis, you know they've gone too far.
/didn't read the article
But that is not generally what simulation theory is speculating about.
Same with people miss-interpreting various ideas as Nihilism. Sure, if you take it from a vary narrow point of your own view, it might be.
In both cases, the people are generally not looking at the subject correctly.
Is there any reason to think otherwise (if one believes in simulation in the first place)? Why simulate the whole universe, when it is sufficient to simulate just one's internal state? Doesn't even require to simulate the high-definition sensory perception, only the mind's latent space — which surely is way more compact. Occam's razor.
Ah, and it is totally not required to simulate your internal state at every moment at all times. It could be just one single moment that captures the feeling of continuity, and then you disappear to the void, but you never realize. See "Boltzmann brains" (again, it is not required to simulate the actual wetware on atomic level, just the compact internal state of the mind).
Simulation theory raises actual questions about meaning and the afterlife, offers some hypothesis to debate, etc.
This entire thread is spawned from an article that is rebutting simulation theory, it clearly is a hypothesis that creates interest.
The TM to run all possible TMs is not complicated. Putting it together is an extended homework problem. Probably even easier to put together the lambda calculus expression to evaluate all possible lambda calculus expressions, or the equivalent in other TM-complete computation models. (We use TMs because they have some nice proof characteristics but we pay for those with the difficulty of "programming" them.) To say our universe is "certainly" in there is a difficult statement to prove, but all possible arbitrarily-precise simulations of it must be, even if an "arbitrarily precise" simulation functions with an arbitrarily-large lookup table of the random results of quantum interactions. The TM that runs all TMs isn't just running all the cute little TMs with 12 states that reverse a string or something. It runs all of them. Even the ones with Tree(Tree(3)) states in them. Even the ones with numbers of states that make Tree(Tree(3)) look tiny. And then the ones that make those look tiny, and so on.
It's just that the resources required to run this are effectively infinite, on the grounds that no universe could ever have enough resources to reach its own execution, let alone anything else.
To wit, T =
(λ 1 1) (λ (λ λ λ 1 (2 (λ λ λ 3 1 (2 (λ 2)))) (3 (λ 4 (λ 4 (2 1))))) (1 1)) (λ 1)
is (denoted with de Bruijn indices) a binary tree containing all closed lambda terms. For example identity may be found at T 1 1 0 1 0 1 1 0 1 0 0 0 1 1 0 1 0 0 0, where 0 = \x\y.x and 1 = \x\y.y move to the left and right subtree respectively.
This is my stance. Nice to see it at the top.
(1) - This may not hold. If so, I'd love someone to explain to me why Godel can't be applied in this way, or extended to cover simulated systems with formal rules.
But that doesn't make it irrelevant to the philosophy of science and metaphysics. We very direly need to resolve why half our physics is continuous and the other half discrete.
Now i haven't done any recursive programming except on some basic programs on the ZX Spectrum many many years ago, but it felt kinda weirdly evil and forbidden when i was able to order code to modify itself.
I approve this troll.
Do we allow marketing or not. We dislike when media over-hypes, we dislike media when it doesn't get the word out.
You can build a better mouse-trap, doesn't mean anything if nobody knows about it.
Simulation suggests that an intelligence created, crafted, made our simulation.
As a Christian the hypothesis fits.
“Store not treasures for yourselves here where moth and rust destroy and thieves break in and steal, but store up for yourselves treasures in heaven where moth and rust do not destroy and thieves do not break in and steal.”
“This is not your home you are sojourners here.”
“The Father is spirit and not flesh He looks for those who worship Him in spirit.”
These phrases make much more sense if we live in a simulation.
Jesus’ miracles and resurrection make sense if we’re in a simulation.
The Bible makes sense if we’re in a simulation.
Therefore we cannot make any conclusion here about simulations.
He was called an Atheist. Just for re-framing God in a way others didn't dig.
So anybody can take a concept of 'God', say your concept isn't the real 'God', and you are an atheist.
Which is the thing, language changes. The word "atheist" doesn't mean the same thing it meant 350 years ago. (Even today, it doesn't have a single meaning, but that's a whole other topic.)