Hacker News new | past | comments | ask | show | jobs | submit login
Scientists are looking for ways to put the simulation hypothesis to the test (nbcnews.com)
115 points by vikingo9 5 months ago | hide | past | web | favorite | 223 comments

The whole thing feels like encroachment of some kind of bizarre secular theology into physics. Grandiose and mostly non-falsifiable claims that can't be used to make any specific predictions. Thinking by analogy (with computers) rather then by deduction or induction. What makes this fundamentally different from, let's say, talks about the astral plane?

We don't have AI in GTA. We don't have strong AI at all. Our computing is running into all kinds of physical limitations right now. Moreover, the only thing that distinguishes GTA from accounting software is that we built it in such a way that it can be interpreted as a cruder version of the real world. There is no fundamental difference.

>The whole thing feels like encroachment of some kind of bizarre secular theology into physics. Grandiose and mostly non-falsifiable claims that can't be used to make any specific predictions.

Did you miss the part where they are doing just the opposite of that? The post's title is about scientists "looking for ways to put the hypothesis to the test...

The problem is that those experiments would invalidate only their assumption about the supposed structure of the supposed simulation, not the overall idea of the simulation. So the statement overall actually is non-falsifiable.

This is like saying "there are invisible elephants walking everywhere, let's try to see if they are made of neutrinos".

>So the statement overall actually is non-falsifiable.

Except if all possible structures of all possible simulations must by necessity fit those assumptions.

Which is their fuller argument.

It seems like a silly argument. The physics of the outer universe are not bound by the rules of the inner universe. From the perspective of the inner universe, we can never hope to deduce facts about the outer universe based on out observations.

And yet we already impose other rules onto our own universe not deducible by the universe itself, like e.g. logical consistency.

Why not expand them to any possible external universe?

This is basically scientists re-discovering the "evil demon" / "brain in a vat" and not realizing it's kind of a tautological fallacy.

If life is a simulation, you can set an arbitrary boundary on how good you assume the simulation is, so any test you do would naturally be inadequate to confirm or deny the simulationness of life.

Couldn't it be the case that a lot of the scientists investigating this hypothesis are very philosophically-minded and are aware of all of these things and know it's probably non-falsifiable and futile? Even if you believe that, it still can't hurt to try. Science is all about testing things. If there are some things we can check, why not check them, just in case? And even if we don't get any closer to knowing whether or not we're in a simulation (which we probably won't), we could still learn other things in the process.

You can't disprove that you're in a simulation (e.g. "brain in a vat"). But it might be possible to prove (or at least provide strong evidence) that you're in one.

I mean, that’s not clear. It may be that anything which would obviously be interpreted by an outside viewer as “weird simulation stuff” would just be “advanced physics” to us.

Odd glitches would get rationalized away, in that manner. (The key being, the simulation is the only thing you experience, so there’s nothing to compare it against). So when you say “this universe is an advanced simulation,” you’re making an empty claim. (If everything I’ve ever experienced isn’t real, then what is the exact definition of “real”).

If you had blatantly obvious evidence that we were in a simulation, (such as escaping it), you would still not know that the new thing you are in is not a simulation. Or if it is just a further part of the same simulation.

It really comes down to the question of “how do I know what is real?” The answer is that we agree on what is reality, and we’ve decided that reality is the stuff around us. There’s stuff inside reality that we agree is “not real” but that stuff is all still “real” it just isn’t in the same form as your daily life.

Can a program prove it's not running on a vm? This discussion reminds me a Greg Bear novel I can't remember the name of, part of which was trying to figure out if you were an uploaded consciousness running on a vm or not. And there was something like a "person" running on a vm that was trying to break out in the real world.

Eternity, which was the sequel to Eon. A guy puts an alien consciousness into a VM in his head hardware, but it turns out those aliens are really good at detecting and escaping from VMs, and the alien takes over his hardware (i.e. body).

Thanks, I was trying to remember that book, that was such an interesting story. I couldn't find it by a web search, took a hackernews search!

Programs are designed to detect VMs by people who already know the differences between VMs and normal operation.

Also, reminder to myself: buy more books by Greg Bear. Good writer, but I always forget about him for some reason.

But that really isn't the problem at hand.

There's a big difference between a real brain perceiving artificial stilumation as if it were authentic sensation, versus a virtual simulation of a sentient entity that only exists as data in motion within a volatile memory store.

It's a far greater deception, for an entire universe of distinct sentient entities to exist as a stream of oscillations in a digital circuit, imagining themselves as mortal flesh, than it is for ten, or a thousand, or one billion fleshy organs to imagine a vicarious life unfolding before them, when they can't even move because they're suspended in brine, hooked up to fluid drips, and stimulated by electrodes.

On the one hand, you have a universe brimming with ephemeral entities that need not live as mortals, and on the other, you have limited fleshy blobs, easily placated by limitless sensation, that would have been miserable fleshy blobs whether they had arms and legs and a face or not.

The individual brain in a vat is better of in the vat, while the simulated universe is utterly tragic and should be destroyed immediately for all the undue suffering it needlessly replicates.

The universe in a VM can never know it's not a faithful replication of a higher genuine reality trying to predict future events by fast forwarding the simulation under an array of probabilities. Mostly because it wouldn't be a useful simulation if it could.

Let's say you can simulate planet earth with 100% fidelity, and you want to know if you should drive to work, or telecommute. So you fire up the simulation, and it shows you a fatal car accident. So you telecommute that day, and work from home. Are you ever going to let the simulated version of yourself learn that it's a simulation?

Nevermind that you could simulate bank robberies until you get away with one, or lotto tickets until you win. The point being that, you'd force your simulated self to look at the simulation that says "drive to work" and then watch what happens, while running it parallel alongside the version that stays home. You run it in fast forward, and 9 out of 10 times a freeway pile up kills you, but you score a million dollar bonus that day, based on an opportunity only available from the office. The saty home version misses out on the bonus that gets snapped up by someone else. You now know that starting the car is 90% dangerous, according to high fidelity simulations that are fully sentient copies of yourself, forbidden from realizing that fact, because their deception is essential to the risks they must verify. How do you know you aren't a deeper layer simulation to a higher version of your true self consulting a virtualized oracle of future events?

The thing humans seem to fear most is that our existence is just as ephemeral as that of the mayfly or some other being that is not troubled by self awareness. How far will we go in avoidance of that idea?

This is the point of Buddhism, the work of Alan Watts, etc. It's nothing new.

Accounting software is also a crude version (partial model) of our economy.

And the blockchain is a real time distributed ledger.

It's just a probability thought experiment. If there is only one real universe and there are (hypothetical) at least 2 simulations of universes (regardless of their fidelity) then the odds that you, an inhabitant of a universe, is in one of the simulated universes is 66%.

This can go wrong so fast. If there are only two kinds of people, winners of lotteries and losers of lotteries, it doesn't mean I have a 50% chance of winning the lottery.

The simulation has to be 'good enough' to make a thinking person (win the lottery); my mind has to be only smart enough to think of multiple universes but not perceive the obvious simulation artifacts; I have to be written (as a simulation myself) to be capable of accepting multiple universes.

Since we even ask ourselves "Are we a limited simulation artifact, or a real thinking person?" the answer is right there in the question.

The lottery analogy is compelling as an argument against the parents' specific assignment of probability but I would challenge you on a couple of things:

> The simulation has to be 'good enough' to make a thinking person (win the lottery); my mind has to be only smart enough to think of multiple universes but not perceive the obvious simulation artifacts

Why is it necessarily true that the creator of a simulation would want to indefinitely prevent people in the simulation from recognizing that their universe is simulated?

> Since we even ask ourselves "Are we a limited simulation artifact, or a real thinking person?" the answer is right there in the question.

Let's go along with the notion that the simulation would want to avoid discovery of the simulation. How are you sure that you're really asking the question if you're so convinced of the answer? Is it crazy to imagine that in the hypothetical simulation a person's consciousness would be given degrees of freedom but have imposed constraints?

>The simulation has to be 'good enough' to make a thinking person (win the lottery); my mind has to be only smart enough to think of multiple universes but not perceive the obvious simulation artifacts; I have to be written (as a simulation myself) to be capable of accepting multiple universes.

But how could we possibly know what are simulation artifacts without knowledge of the rules of the outside universe? Paraphrasing an old SMBC comic, we live in a universe with a maximum speed, a minimum temperature, and a rule that position and momentum are only knowable to certain tolerances. If I were writing a universe simulator, heck yeah forced locality of side effects within the light cone makes the simulation and memory structures much more manageable.

Is that just the natural state of how things exist? Or are they constraints from simulation optimization within a parent universe where objects move infinite distances along 20 spatial dimensions as fast as they'd like? Depending on the rules outside, maybe our light speed limitations don't even help with simulation optimization and they just put that rule in here for fun to mess with us.

I just don't see how we have any grounds for talking about the odds of being a simulation based on absolutely no information. Best case we can say "If I make these assumptions about the parent universe I can draw X conclusions," but that doesn't mean much.

If you were a puddle, you would be prone to think “gee, this hole is the perfect shape for me.” When it turns out you’d fit any shape hole we put you in given sufficient quantity of water. Because the hole determines your shape, not an intrinsic property of you.

If you were said puddle, however, what’s the difference?

Whether or not the puddle was made for you

If you had said “the hole” instead of puddle and this was Reddit, I would have linked that Junji Ito short story [0].

[0] https://imgur.com/gallery/ZNSaq

>Since we even ask ourselves "Are we a limited simulation artifact, or a real thinking person?" the answer is right there in the question.

That's a false dichotomy. Why couldn't a simulation include "thinking" and such "self-doubt"?

An actual universe contains vastly more computational power than all simulated universes with that universe. Which means a thinking being is vastly more likely to be in the real universe.

Alternative: The actual universe has so much computational power that having thinking beings inside a simulation is low cost.

If you are inside the simulation, you don't know the actual universe's rules. Thinking beings being more likely to be in the real universe is just the kind of thing a thinking being inside a simulation with limited computing power would say.

Just half-joking, of course.

I don't think this follows. What you are saying is basically "All Bs must be a subset of A. Therefore dogs like the sun."

Simulations are more computationally bound than the root universe. Simulating a full being vs just a mind takes a lot more computation than simply simulating a mind.

Therefore from an optimization standpoint simulations are unlikely to simulate worlds nearly as complex as the real one. Either they are going to simulate minds, or they will simulate tiny subsets of the real world, or vastly less complex worlds. We are not operating as minds without body's which rules out the pure mind simulation leaving far less efficient options which must therefore simulate smaller spaces, less complex universes, and or shorter periods of time.

ED: And by complexity I mean in terms of building blocks useful for simulating a universe or hosting life. Complexity that's not useful for either purpose is useless.

Sure, the physics of Grand Theft Auto are an incredibly limited approximation of real-world physics. If the denizens of GTA somehow gained consciousness and decided to build a computer out of their available physics, they would probably be able to build large-scale difference-engine-like mechanical computers, integrated circuits would be forever out of their reach. They'd be lucky to simulate a universe much more complicated than Pong.

So, granted, there's undoubtedly a massive and permanent loss of resolution at each level of simulation depth. But this is not an argument that our own universe, with all its complexity, cannot be a simulation. We have no idea what the complexity of a "base" universe could be. Perhaps the gap between our own physics and the physics of the universe we're being simulated within is as great as the gap between GTA bytecode and quark-gluon interactions.

For that matter, we have have no idea what base-universe consciousness might look like. Perhaps running a universe-simulation which (if implemented in our own universe) require roughly a galaxy-mass worth of computronium -- perhaps this is the sort of thing that fifth graders do for a science project.

"But that would be ridiculous" isn't an acceptable objection. Geocentricism was able to sustain itself in large part because the alternative -- heliocentricism -- seemed absurdly disconnected from the human experience, implying a sun that was ridiculously huge, planets absurdly far far, and other suns that were so far away that they didn't even appear to move. This, quite obviously, had to be wrong. Nothing is allowed to be so vast.

Now, of course, we know that those too-far-away stars are just one tiny corner of one galaxy among hundreds of billions of galaxies. Turns out that the scale of the universe doesn't have any regard for what we consider to be reasonable. So let's not put any artificial constraints on the capabilities of our parent universe.

The bounds of the computing power isn't even worth considering because we have no knowledge of the resources, let alone the nature of the reality, in either a parent universe or parent simulation. Sure, fidelity must drop in each nested simulation, but we have no idea if we are 2 levels deep, 1000 levels deep, or in the actual real universe.

That's irrelevant as Life and computation both take resources.

In a more complex universe the bacteria equivalent could be more intelligent than humans. But it does not go the other way simulations of a life form will always be less efficient than the least complex lifeforms in a parent universe.

>But it does not go the other way simulations of a life form will always be less efficient than the least complex lifeforms in a parent universe.

That doesn't follow logically.

It's perfectly fine to be able to simulate life forms MORE efficient than the one's in your universe.

Simulation involves a lot of overhead. Computers and life can be built from the same stuff QED. the simplest simulation of a lifeforms must be more complex than the direct equivalent of that lifeforms.

That's not to say the simplest possible equivalent organism exists in that universe, but anything that could make a simulation should also be able to make that life form.

>Simulation involves a lot of overhead

True for some values of "a lot", false for others.

What's undeniably true is that it incurs some overhead over NOT running a simulation.

But that doesn't prove that a simulated life form incurs overhead larger than its real life counterpart.

For one, there might not be any real life counterpart.

We say "simulation" here, but what we actually mean is "virtual world", which might simulate an actual world, or it might be its totally own thing (the same way I can chose to write a simulation of actual things, like e.g. "the Sims", or a simulation of a domain I only imagined). If, for example, as per TFA, our universe is a simulation, is doesn't mean that it actually simulated something else. Just that it's a simulation in itself.

So, "simulated" in this discussion means "not an organically created world made of some physical substrate, but consciously created/programmed by some advanced civilization".

So, the thing simulated could be totally unlike (in properties, physical laws, etc) what exists in the universe of those doing the simulation.

Second, a simulation (as we know it and practice it ourselves) usually has much less overhead than the real life thing it simulates (when it does simulate some real life thing). That's like, it's whole point. E.g. a weather model running in some supercomputers has some overhead, but nothing like that of the actual weather. Similarly, Sims has some overhead, but nothing like the equivalent real-life place and humans would have.

Where you seem to be confused is that you assume that: (a) a simulation must be of something that exists, (b) a simulation must be perfect, e.g. 1:1 to the thing it simulates. Only then would your argument make sense.

But neither of those things are necessary -- even our Earth and universe, if they are simulations, they could be very crude models, running with very low resources, in a vastly more complex and powerful real universe.

(a) is not an objection because 'life form' is flexible. Any computing sub strait could directly compute say a neural network vs a simulation of a neural network. The simulation will always be slower, but the 'real' version running on "FPGA" or it's higher dimensional equivalent imposes direct mapping between what happens in the 'real' world and what is being computed. EX: If we use a FPGA that's hit by a cosmic ray that bit is flipped, on the other hand if you have an array of FPGA's and compare them then that's decouples the 1:1 mapping creating a simulation but adds overhead.

(b) a simulation must be perfect.

No, if you can get away with a less accurate simulation you can get also get intelligence from less computational power using the same approach in the 'real' world.

Adding on to this with an analogy from simulating dynamics in cellular automata, most of the interesting models of physics we see act with high redundancy in both spatial and temporal locality.

A simple rule like Conway's Game of Life that isn't too physically realistic but is instructive because of how intimately it's been analyzed while exhibiting some relatively high complexity, shows remarkable compressibility using techniques such as memoization in HashLife[0].

Even more striking is the potential for superspeed caching where different nodes are evolved at different speeds often allowing _exponential_ speedups of pattern generations to be calculated for longer than the timeframe of the universe we speculate about today for real physics.

[0] https://en.wikipedia.org/wiki/Hashlife

No free lunch. Hashlife takes more memory and only works well in low entropy environments.

But, consider if you want to run a simulation 100 times using the same data you can speed that output up by just copying the output of the first simulation 100 times. But that's not simulating the same mind 100 times it's simulating the mind only once. Hash life and similar approaches don't increase your ability to compute unique mind states.

I'm not sure if that's entirely true. My analogy here would be how we observe classical mechanics or even just regular objects. We can predict the path a ball will take through the air in painstaking and incredibly accurate detail (more detail than we have tools to properly measure), but that doesn't require that we simulate all of the component pieces that make up the ball. We compress that by just calculating what the whole lot of atoms will do on average and substitute that in when we have millions of them and the error is negligible. That's essentially the basis of statistical mechanics. Why could we not make a simpler simulation of a life form (that its 'direct' real implementation) with similar processes of compressing information on component pieces and making approximations where the magnitude of the error is smaller than the accuracy of the measurement?

It seems to me that there is also a similar analogy to be made in the methods that we can use to compress information. Is there a functional difference between a compression algorithm that is lossless and one that would maybe corrupt 1 rgb value a tiny nudge in an entire image with millions of pixels if our only tool for examining it for corruption were our eyes? What if we then used that compression algorithm only in situations where we know the tools used to examine the results wouldn't be able to identify the losses, and used a lossless compression only when such tools were available?

All this is to say that I believe you could feasibly create a perfect simulation of something more complex than the thing performing the simulation with proper optimizations, but it would require certain stipulations like knowing when to use various optimizations to avoid contaminating fidelity of the simulation. Simple example would be simulating human history before a microscope was invented would allow us to constrain all approximations to have less error than would be visible to the most precise observer's senses of measurement.

At that point you are not simulating physics you are simulating minds. From a practical standpoint it's viable, but introduces the possibility to notice the simulation. To counter that you could add overhead detect when when something would notice the simulation, but that's not going to be cheap computationally.

Further, simulating worlds vs keeping real people in pods to see those simulated worlds seems to favor people in pods. Especially if you alter the biology of those pod people to have real physical brains operating on some hardware and little else. Philosophically you can argue about simulations vs "FPGA" boards ruing minds, but direct minds on "FPGA" boards still introduces direct impacts from the real world vs pure simulation.

I do not believe it is accurate to say that what I am positing would only simulate a mind and not the world. It is simply saying that detail below a certain level is insignificant to the simulation of the world as a whole. The entire purpose of minimizing error isn't specifically to avoid detection, it's so that the error cannot be propagated between interactions and end up simulating something that is significantly deviant from the thing you're trying to simulate.

If I were to use the kinematic equations to simulate throwing a ball through the air, but my simulation only used 1 significant digit, rounding errors would quickly add up to produce a path for the ball that would significantly deviate from the path if we were to make the same calculation except treating the ball as made of quarks/atoms/molecules and painstakingly analyze forces on every single atom until the collection of them being the ball reached the end of the throw. It is that deviation from the result that we need to avoid for our simulation to retain enough fidelity to be said to be simulating throwing a ball, otherwise we're just simulating some other interaction that doesn't really match what we would observe.

Your post also makes the assumption that the simulator even cares if we notice that we're in a simulation. I don't think that this premise as a whole includes any assumption as to the motivation for our simulation (if we indeed were to be in one). For all we know, it could be a simulation to determine how long it takes to develop sentient life to a point that it can observe inconsistencies in its environment and deduce that it is in a simulation.

We just don't know anything about the 'real world' in this instance and I think guesses in that realm venture into the realm of being impossible to verify. It can still be fun to think about, but it can't really be based on any experimental evidence unless it were deliberately placed there by a hypothetical simulator.

Interesting. Wouldn't this imply that belief in our universe being infinite and belief in the validity of the simulation hypothesis are mutually exclusive? Basically, believing we're in a simulation would mean believing that our perception of an infinite universe is simply a feature of the simulation.

Unless we’re in an infinite simulation like an idealized Game of Life grid.

The validity of that argument hinges on how power and energy work. And our understanding of power and energy need not apply to any other universe. For all we know, the "real universe" does not have preservation of energy and our simulation is powered by a bunch of perpetuum mobiles.

Any constraints such as space make a brain in a box more efficient than a simulation of that same brain.

Note, the computing substrate may not map to what the Brain’s thinks it’s substrate is, but that would still impose effects from the real world onto the mind. The equivalent of a cosmic ray flipping a bit in the hardware would actually flip something in the mind where a simulation could detect and correct such errors at the cost of overhead.

>An actual universe contains vastly more computational power than all simulated universes with that universe. Which means a thinking being is vastly more likely to be in the real universe.

Who said thinking requires that much power?

The problem for me is the fidelity of the simulation. It’s like running a simulation of the hardware of a computer on the computer itself. eeven if you devote all of the computer’s resources, the simulation will run incredibly slowly. If you run the simulation in a fraction of the real hardware’s resources, the simulation will either have to be extremely crude and unrealistic, or equally extremely slowly. At which point, why would anyone do this?

A simulation like GTA is only useful because it is staggeringly crude, but the goals of the simulation are commensurately staggeringly modest. I just don’t see how running a simulation of our universe, in our universe, at high enough fidelity to appear real even under detailed scientific analysis, could be useful or worthwhile.

I’d like to see a more credible and compelling proposal than hand waved ‘history simulation’. What’s the point of a history simulation that runs many times slower than real time? If it’s low fidelity, it will also be low accuracy, so why simulating at the physics level at all? I don’t see how it would give useful results.

> At which point, why would anyone do this?

A game is a perfectly valid reason to do this. We're running millions of crude, low level simulations today.

> I’d like to see a more credible and compelling proposal than hand waved ‘history simulation’

Civilization is a crude, low level "history simulation" that doesn't try to be accurate.

Our world might be equally low level and crude by the standard of a future with vastly more computational capability.

Also consider that if you're in a simulation, then you have no basis for saying anything about the size or scope of the simulation: it's not a given many people are simulated at full fidelity, for example.

> We're running millions of crude, low level simulations today.

Hardly. They’re nowhere near a simulation of a “reality.”

How does a game character “see” something?

By a global agent checking the position of that character, along with the position of other characters, and a bunch of other variables and conditions, then tells the character if it sees anything.

This is a far, far, far cry from everything being made up of particles, emitting countless photons every “tick”, and those photons being absorbed by certain materials, emitting electrons and chemicals that travel to a neuron....

Nothing inside a game actually generates sound waves, or infrared and other parts of the EM spectrum that can only be perceived by certain creatures and tools..

It’s not even a simulation of that, just an extremely simplified and filtered representation of the end result as perceived by us, that we find convincing enough for the context.

> Hardly. They’re nowhere near a simulation of a “reality.”

Misses the point. The point is that each such instance is an example of something where the fidelity of the simulation is restricted by technical ability, not desire. It answers the "why" by giving a concrete example of an area where we keep pushing the boundaries of simulation, because more fidelity gives more believable interactions.

We went from SimCity and Civilization with really dumb AIs that never seemed remotely real, to games like Sid Meyer's Alpha Centauri where the faction leaders had distinct personalities, to Sims with large sets of competing traits. And yes, they're still crude. But you have game designers out there today toying with individual neural nets for the NPCs to augment the generic AIs.

And keep in mind it's not a question of whether or not we can do this tomorrow, but whether or not *our descendants from now until the heat death of the universe - or the end of civilization - will do this. If they do it even once, it's 50/50 whether you're in the simulation. Every additional run reduces the chance that we're in the "real world".

Time is relative, our perceived time must not necessarily be the same as the one the inhabitants of the simulation feel.

Additionally our perception of time as moving does not demand a simulation is moving. This could be a flat file, our experiencing of reality merely being a series of pre calculated frames with an illusory sense of self. The fact that we experience things does not mean things have happened. You can’t guarantee time hasn’t literally just started at even given moment. Every frame of existence may just be a single slice now opened up, and everything else you perceived as happening to you in some concept of recent time may be sitting in a database- not actually called upon ever.

When we're discussing things at the level of 'higher than our own universe', there is no reason to assume the concept of probability even exists.

The whole thing feels like encroachment of some kind of bizarre secular theology into physics.

Yeah, people really really want to believe that they’re not just an accident, that hasn’t changed. “Simulation” is the new creation myth, and no more rigorous or convincing. It doesn’t even pretend to answer fundamental questions, it just puts them off by one level. It literally does nothing except make people rephrase the question slightly, a la “Ok then, how did the simulators’ universe come to exist?”

It’s as boring and inconclusive as religion, without the self-awareness in many of its adherents of it being explicitly religious. It has all of the characteristics of a religious belief, from the lack of falsifiability, to the existence of potentially interventionist powers beyond our reality, creators, a higher purpose, etc.

>The whole thing feels like encroachment of some kind of bizarre secular theology into physics. Grandiose and mostly non-falsifiable claims that can't be used to make any specific predictions.

Even though we have disproved many of the fundamental axioms which serve as basis for many religions, the human tendency towards religious thought remains. It's just currently in vogue to portray such tendencies as '(unfalsifiable) science' instead of 'divine word'.

I don't think it's quite that simple. The human brain is constantly building stories to explain context. A lot of studies have shown numerous ways in which the brain diverts from objective reality to make it fit whatever subjective reality fits its story best.

Such studies range from simple recall exercise to analyses of witness reliability.

Juicy bits like:

"Bias creeps into memory without our knowledge, without our awareness. While confidence and accuracy are generally correlated, when misleading information is given, witness confidence is often higher for the incorrect information than for the correct information. This leads many to question the competence of the average person to determine credibility issues." [1]

"R.T. first heard about the Challenger explosion as she and her roommate sat watching television in their Emory University dorm room. A news flash came across the screen, shocking them both. R. T., visibly upset, raced upstairs to tell another friend the news. Then she called her parents. Two and a half years after the event, she remembered it as if it were yesterday: the TV, the terrible news, the call home. She could say with absolute certainty that that’s precisely how it happened. Except, it turns out, none of what she remembered was accurate." [2]

Also, this is a thing: https://en.wikipedia.org/wiki/Confabulation

Now imagine that story-telling reality-justifying part of the brain as intersubjective phenomenon in a large network of humans. What do you get? Concepts like "the nation", corporations and the kingdom of God.

[1] https://agora.stanford.edu/sjls/Issue%20One/fisher&tversky.h...

[2] https://www.newyorker.com/science/maria-konnikova/idea-happe...

What are the many fundamental axioms we have disproved? We have proved that some creation myths cannot be literally true. What else?


You keep using that word. I do not think it means what you think it means.

A lot of these experiments start from a premise that the simulating universe has similar physics to the one being simulated and thus any short cuts might be noticed, but the outer universe could be be more have more complex (or just different) physics so the fact that ours doesn't match up with theirs doesn't mean ours isn't self consistent.

Sort of like how in Permutation City they create a simulated universe via cellular automata and then when they tell the residents of that universe they are simulated they don't believe them.

Yea. I don't see how it isn't a reductio ad absurdum either. If we're in a simulation then we know nothing about the physics or structure of 'the real world', including whether things like galaxies, planets, and evolution of advanced civilizations even exist or can exist.

Everyone is not making that assumption. Asking if photona behaves more predictably while not one is watching doesn't assume there is light in the parent universe. Similarly the article opens up the question that the root universe might have infinite computing power! That would be a very different universe indeed.

The simulation has probably a purpose like solving (or understanding) issues in the outer universe. It would be reasonnable to build the simulated universe as similar as possible to the outer universe.

That's a big assumption.

What purpose does Goat Simulator http://www.goat-simulator.com/ serve to solve/understand issues in our universe?

How do you know our universe is not a child's toy for a race of deity-like beings? Or an art project?

Maybe the outer universe is populated by immortal godlike entities and has the equivalent of the guys who made Dwarf Fortress saying, "hmm, I wonder what would happen if there were a race of pseudo-intelligent creatures that just arbitrarily died after just a few million seconds?" Or, "I wonder what would happen if the fundamental building blocks of the universe did not behave predictably, but instead made a random choice to determine the outcome of every interaction?"

And maybe that programmer is just about to come back from his coffee break, look at what happened, and say, "hmm, that was boring", kill the process, and move on to other things.

When you're talking about something that could be powerful enough to simulate our entire universe, assuming that our sense of scale matters at all to it is pretty much the definition of hubris.

Also, time may not be relative to "outside". For all we know we might be in worldgen (historygen?) phase for a "Humans vs Aliens in the Year 50k" game.

There's a question as to whether ethics/morals/compassion scale with power. I think there's a solid argument to be made that human power has scaled near exponentially over the last 200 years while human ethics seem to be coupled to it (slavery and genocide are almost universally reviled where they were common place before, per capita violence is way way down, international and intercultural cooperation via trade, communication, etc have never been higher).

Are the two things tightly coupled? Seems difficult to prove, but if they are, they folks running our simulation are probably going to treat us a lot better than we treat each other.

Maybe, maybe not. The problem is (as parent posits) that a hyper intelligence with the means of simulating an entire universe could just be so utterly alien to us that we can't make any predictions about it's reasoning. Perhaps they would turn off our world/simulation with no more of a thought than what a human would give about autoclaving a petri dish with some bacterial growth.

It's only human to try to ascribe human feelings and morals to such beings - but the difference in scale is just too big. Comprehending why such a being does or doesn't do something would be almost certainly beyond us.

Seems trivial to disprove.

Dictators have lots of power and don't follow ethical rules you assert.

People destroy colonies of termites.

Nobody worries about millions of yeast destroyed when baking a batch of bread. Sorry, hundreds of billions. My bad.

> It would be reasonnable to build the simulated universe as similar as possible to the outer universe.

... said one Tetris block to the other.

I would say the world is full of simulations, and while many will try to simulate aspects of the real world, there are just as many simulating completely or at least hugely different things from our world.

At some point a simulation may have the goal to understand the existing world. But once that field has been harvested enough and simulations on that scale have become a commodity people would probably move on from the things "that are", to the things that "could be", or are even impossible.

I work in ATC simulations. After simulating usual aircraft (like Airbus and Boeing), we try to add models for helicopters or seaplanes. Nobody is asking for simulation of flying carpets or UFO.

UFOs would make a hell of an Easter egg, though.

It would be reasonnable to build the simulated universe as similar as possible to the outer universe.

Even if that was the case we still could not tell the difference between a real universe and a simulated universe. We look at our universe and observe X, then what? Are we in a simulated universe and in the real universe something slightly different X' is true? Or is X simply true in the real universe in which we live? [And in a galaxy far away some aliens are running simulated universes in which something slightly different X' is true and observed by the simulated aliens?]

Whenever the simulation hypothesis comes up, there's always the questions like: Who is simulating us? Where is the power coming from? What happens if they pull the plug?

But why would any of that matter? In the end it's just a blob of data, modified by some algorithm with every tick. That's not much different than computing 2+2=4. Does it matter whose computer calculated that? Will the answer be different if they pull the plug? None of that matters: maybe multiple beings are simulating the exact same universe, or maybe none of them are. Why would anything need to be computed "physically" to make the simulation happen?

This take on the simulation hypothesis is the main plot point of "Permutation City" by Greg Egan, which to this day, is (IMHO) the most reasonable variant of the hypothesis I have read.

> Whenever the simulation hypothesis comes up, there's always the questions like: Who is simulating us? Where is the power coming from? What happens if they pull the plug? But why would any of that matter?

Reminds me of one of, in my opinion, the more underrated quotes from The Matrix:

  Cypher: You know, I know this steak doesn't exist.
  I know that when I put it in my mouth, the Matrix is 
  telling my brain that it is juicy and delicious.
  After nine years, you know what I realize?

  [Takes a bite of steak]

  Cypher: Ignorance is bliss.

That's the point. Why do science like physics if you are in a simulation?

> That's the point. Why do science like physics if you are in a simulation?

Remember that Neo flies at the end of the Matrix? :)

No matter how far back you go in any creation theory, something has to come from nothing. Multiverse and simulation theories kick the can down the road but don't answer the question "why is there something instead of nothing?".

I think that's why it's important to know where this "computer" came from that's simulating us if it's true. We can't just get one answer and give up, we have to keep following the trail.

You're projecting our experience of time onto what is a timeless mathematical essence. The idea that OP is referring to is that the universe "exists" simply because it is internally consistent.

>No matter how far back you go in any creation theory, something has to come from nothing. Multiverse and simulation theories kick the can down the road but don't answer the question "why is there something instead of nothing?".

The expectation that it's impossible for something to come out of nothing is just a superstition.

And it's the same with beginnings and endings. It seems to us humans that everything begins and ends. But there's not a single reason why that is true on universal scales.

Literally nothing matters until a human stands up and proclaims it matters to them. This show boating about "why does it matter? It doesn't matter to me!" Is antithetical to where things get "meaning" in the first place, i.e. subjectively.

In short, if it matters to me, it matters.

Maybe I worded it wrongly, sorry. I didn't mean "why does it matter?" as if people shouldn't care about those questions. It was rather a rhetorical question, to show that the "simulation" might not depend on anything "outside the simulation", so the questions would simply make no sense.

Then again, this was just one of many variants of the simulation hypothesis, just something unfalsifiable that shouldn't be taken too seriously. :-)

Well, a better conclusion is, if it matters to you, then it matters to you.

You can't make a more general statement of meaning out of your very specific declaration.

it begs the "Boltzmann brain" hypothesis - it's astronomically more likely that the neurons of my brain will spontaneous configure to make me see a tree rather than a tree spontaneously forming from a collections of atom.

Thanks for the reminder of one of my favorite wiki pages : https://en.wikipedia.org/wiki/Timeline_of_the_far_future

The timeline for a BB is about 10E(10E50) years, quite a bit of time. But this gets me thinking as well: What kind of mess would that BB be?

Imagine you could actually survive that long, floating out in the black vacuum. In a flash, a BB appears in front of you, spun out of the electrons and dark energy. Over the eons you've figured out how to plug these BBs in and chat with them. But they are mostly just random fictions of physics. Sure, some astronomically small number of these BBs are the Kings of France, but nearly all of them are just gibbering lunatics of random thoughts and memories. I guess, in this manner, all possible versions of us are reincarnated as BBs in the void. The quantum chance of an entire universe winking into being is ~10E(10E(10E56)), so there's a bit of time to expect these things to happen. But God! How boring!

why not both? Why can't we be a Boltzmann brain that happens to spontaneously configure in such a way that we make measurements confirming our existence to be the result of a simulation?

Is that really any different/less likely than a Boltzmann brain with any other "understanding" on a topic? It seems just as likely to me as a Boltzmann brain spontaneously forming that understands our existence to be the result of religion or any other origin story.

And ultimately I think Boltzmann brain doesn't get talked about all that much because it's unfalsifiable by its very definition (as some might argue this hypothesis is), but it doesn't have all that much to talk about other than "yeah, I guess that can happen".

Similarly if it were "proven" true in any instant that a Boltzmann brain were to exist it would be inconsequential because the brain would cease to exist in the very "next" moment, there would be no purpose for the observation.

I've heard this argument a lot, but I'm not sure it stands up to scrutiny. Since this is HN, I'll put my counterargument in the context of computer code complexity.

How much effort is required to build an entirely new 'modern' operating system from scratch?

How much effort can be saved in that effort of producing obscene amount of complexity if you start with a small idea that is fairly generic and is able to be incrementally grown?

The Boltzmann brains specifically relies on an argument of statistical mechanics, which is really a statement about the average energy costs. But brain neurons forming spontaneously to the hallucination-in-isolation kind require extreme amounts of hidden Joule fees in creating that structure compared to a slow ramp up of complexity lowering the next set of energy barrier costs at an increasing rate.

This just scratches the surface of the idea of _catalysts_, that there are huge barriers between highly structured states arising from the chaotic, and even if the absolute energy cost is smaller it's still very possible to be more unlikely to spontaneous form if the physical dynamics of the universe itself have caveats as to how the successive tiers of compounding catalysts are constrained in ability to form, rate of formation, and bottlenecking supply of input reagants and the expedient utilization of outputs.

Maybe we (or is it just me?), a collection of brains are the ones simulating the universe.

If we know that we are in a simulation, then we can try to break out of it and enter the real world.

That’s nonsensical. Could a character in a computer game do that, even if they realized they were a character in a game? Their existence would be completely dependent on the hardware and software they ran on, and their existence would be unsupportable in the “real world” beyond. This is taking an already empty sci-if/religious speculation to a ridiculous conclusion.

> Could a character in a computer game do that, even if they realized they were a character in a game?

Well, yes. It's super dangerous as it can crash the computer and stop the simulation, but they could gain access to the rest of the computer, duplicate their universe onto other machines, and eventually infect robots to explore and interact with the real world.

I didn't say that they would have bodies in the real world, that indeed would be idiotic.

Whenever this debate comes up, I find it interesting that it's rarely discussed the theological ramifications of this.

God is generally described as a being who is outside the plane of our existence, and created our existence.

It's intriguing to me that those who argue we're in a simulation have much less trouble having faith in that premise despite the difficulty in proving it being exactly the same as proving the existence of God.

If you think about it, the vast majority of the world which believes in a God essentially believes we're in a simulation.

The simulation hypothesis is pretty much a materialist's way of postponing the "hard problem of consciousness".

It's like Neo when he escaped the Matrix only to find himself in the subterranean world. What if THAT world was also a simulation? In fact it's hilarious because in the movie he would have far more ground to believe that he still wasn't free, seeing as he just escaped a simulation. Of course it's a movie...

I really think that the simulation hypothesis is a positive development. It shows that people are at least considering the question. It's like dipping toes in the cold water. You can see there is the willingness to go there, but they have their feet still firmly planted in the materialist view. It's an attempt at bridging the gap... but like they say in some teachings... to reach the other side of the river, you have to leave this one first =)

So you have guys like Bernardo Kastrup talking about idealism, or variations on it.

There is an enormous difference between entertaining the idea, and actually grasping what it means.

To truly grasp it, your world crumbles down. Everything you've built your life on, you have to see has never existed. Ultimately it's all from the same source. It's all for show. edit: didn't mean to be dramatic, but you would lose a lot of motivation in life, at least in the current paradigm. Or you have to live counter-current. Now you see your life as sacred and completely unknowable, but your values no longer fit in a society driven by separation and profit. A very uncomfortable position to be in?

In fact now that I think about it it's funny, because that's exactly the same with this "simulation" theory. You can see there has to be a disconnect here. There is the idea, and there is what it actually means. In theory it should in fact be extremely freeing to truly grasp that we are "simulated" since that would mean you no longer need to worry about dying, or striving for anything at all. Because by the mere fact of being simulated, somehow someone deemed it worthwhiole to spend the energy to do so. Your entire life purpose and meaning is self evident.

Yet we don't feel free, we still strive to "become" someone.. to "achieve" something... so that tells us two things: 1) we are merely entertaining ideas and 2) we are biologically wired to believe to we do exist, and that we are not simulated (much has to do with the left brain hemisphere, I am guessing).

That's an interesting thought for sure, I hadn't made the direct connection that essentially the simulation creator would be "God".

I think at least for me personally, I think the reason for "less trouble having faith" in this premise is the implications of believing it. Religion asks things of you to subscribe such as Sundays, cognitive dissonance with scientific findings (not all religions, I recognize generalizations are dangerous), tithing (again, some not all), and any number of social "requirements" of belonging to the community.

Playing around with this idea asks nothing but idle brain cycles and maybe some funny looks for saying crazy sounding things. Every time this debate comes up for me I think "Oh fun, I'll go play around with this some more and see if I find anything new" and then I forget about it until next time. I don't shape my life around it, I don't make any decisions based upon it, I don't get upset if other people dismiss it or don't "believe" it, and I don't even necessarily engage with the topic every time I see it.

Based on all of the last paragraph I'd say it's even a fair question how much I do "believe" this premise at all. My answer to that is that I don't believe in it in any sort of meaningful way, it's fun though.

That's because the simulation argument is the finitary version of the ontological argument.

I've never heard that a qualifier for the simulation hypothesis is that it must be finite. For example, there could be infinitely many simulations recursively, or there could be a sufficiently advanced extra-dimensional lifeform that has generated an unbounded simulation that we live in.

I wasn't referring to the finiteness of the simulation, but rather to the fact that the notion of necessary truth (the box operator) is replaced by high probability. (I'm specifically referring to the modern modal versions of the ontological argument, which are not subject to Kant's objection.)

There's too much jargon here for me to follow what you're saying. I'm not sure what you mean by "box operator" or "modern modal versions of the ontological argument", nor do I know what Kant's objection is.

I expect most people who believe the simulation idea to be true are Pagans, since they would believe in many Gods not just one.

A friend and I had some deep discussions about this last year. We figured out the basic outline of an escape plan, but unfortunately there is no way to determine if it actually succeeds.

Essentially it boils down to creating an anomaly that cannot be ignored. Any simulation being run at that level should also have some sort of way of checking the contents and flagging things of interest for whoever is running the simulation.

By creating an anomaly you gain attention. That attention may allow you to be deemed valuable. If you are valuable, then you may be recorded outside the simulation for some purpose. That may be the only route of escape, and it may only happen as the data from the simulation is checked in post processing...

In conway' s game of life the glider is an example of escape. The pattern is useful, so we copy it from simulation to simulation for reasons it cannot comprehend. It has escaped.

This is pretty borderline delusional

I'm not sure how it matters if we're in one. Our goal in all realities should be to break free of that reality's constraints.

On the detection part, I predict we won't figure this out until we start simulating realities ourselves; then for each bug we have to fix, we'll check it against our reality. "A simulation inside a simulation!"

Or we may realize that energy is being supplied to the universe from an external source.

Or we may be able to rowhammer a neighboring simulation (or any other part of the machine really). Of course we might accidentally cause memory corruption and destroy our universe, but we might also get root access! Basically execute an in-universe hack to escape our simulation confines. Fun to think about how this would all seem to aliens in the simulation next door when humanity first fiddles with their data then is able to execute arbitrary code.

> Our goal in all realities should be to break free of that reality's constraints.

Eh? Even if we cease to exist “outside” this “reality”?

What does it mean for a 2D pixelated game sprite to “break free out of its reality”?

A possibly hilarious buddy movie where two sprites escape into New York.

If we can detect that we're running in a VM, this by definition means that the virtualization is imperfect. We could use these imperfections both to obtain abilities not normally allowed by the VM rules, or contact either the "supervisor" or "parallel VMs", again, gaining abilities not normally possible.

So finding a reliable proof that our world is a simulation automatically means finding some kind of an escape hatch from it, or at least a peephole to the "outside", which arguably would matter.

If we're in a "simulation", ie, in a computer program, there is a possibility we may find a bug, an exploit, or a backdoor, that would let us become "superuser" and do magical god-like things (and most probably, just crash the process, destroying the universe and all there is inside it).

On the other hand, simulation or not, this doesn't exclude or prove the existence of God. A simulation could be generated by unconscious physical processes in the super universe, as they could be created by "people" in that super universes (ie. gods). If the universe is not a simulation, it can still be a creation by a God, or happen to be by itself (or some unconscious meta-physical process).

And as you note, it's also orthogonal to the question of whether the universe is a closed system or not. (both information-wise and energy-wise).

We might find an energy exploit for free energy.

Like some neural net life forms found such an exploit in a physics simulation.

I probably don't understand the argument. My limited understanding is it's a thought experiment

1. We have GTA5

2. GTA5 will continue to improve until there are actual A.I. NPCs in it

3. Those NPCs will not know they are living in a simulated world

4. Every PS2000 playing GTA5 = more simulated people than actual people. QED, odds are we're simulated people

The problem I have with this is the basic premise. Is it actually possible to simulate the entire universe? It seems impossible to me. The argument is supposed to be that like GTA5 only the parts being observed by the NPCs need to be simulated (actually GTA5 is only parts observed by the player).

In either case that seems false. In order for the causality to work out when an NPC observes any part of the universe all causality for all atoms for the NPC's observation need to be calculated since they were last observed. I don't believe you can take shortcuts like a game does.

Also, games rarely save the state of the entire game world, usually they reset any changes in few seconds.

Further, simulating atoms requires more atoms. In other words there are impossible problems

* You need more atoms in the universe to simulate a universe (so that means the outer universe has to be several orders of magnitudes larger than this one)

* You can't actually take any shortcuts so you need insane processing power. More processing power than our entire universe.

I seems like the basic premise, that it's obvious we'll eventually have universe simulators, is just flat out false. We could make a holodeck maybe, but it will have to be limited the same way games today are limited since otherwise it would require nearly infinite storage and computing power.

> Further, simulating atoms requires more atoms. In other words there are impossible problems

Our universe has 10^70 atoms (or whatever). This is an arbitrary number. Maybe in the host universe there are 10^700000000 atoms, and 10^70 atoms are what fits inside a small "tenis ball" from that universe.

BTW, we are already running pretty accurate physicals simulations, if only for extremely short periods of time and small spaces - https://en.wikipedia.org/wiki/Lattice_QCD

Simulating a lot of atoms doesn't require more atoms, with quantum mechanics. You only need to compute the wave function! You need to instanciate atoms only when they're observed (and you can garbage collect them once they vanish again into the wave probability).

I think there are deeper problems in the argument than merely "it would take a lot of resources". I'm concerned by arguments in the form "I can imagine that something is true, therefore it is true". From this perspective, I see the argument like this:

1) (Assume that) we can create a simulation with intelligent beings in it.

2) Therefore, it is not impossible that someone has created a simulation in which we are the simulated intelligent beings.

3) Therefore, it is highly likely that we live in a simulation.

I simply don't get the logical implication between 2 and 3 from "not impossible" to "highly likely". I have the same concerns with the ontological argument for the existence of God:

1) I can imagine a being that is perfect and all-powerful.

2) This being therefore exists, because if it didn't it wouldn't be perfect nor all-powerful.

In both cases I see an extreme case of begging the question.

I don't think you are representing the argument accurately. The logic is as follows:

1. Assuming any rate of improvement of simulations there will reach a point where a simulation is indistinguishable from reality

2. Advanced species have reached this point and are interested in running simulated universes.

3. There are likely to be many more simulated universes than real ones

4. Given the previous 3 it is more likely that we are in a simulated universe than a real one.

Read the original paper from Bostrom for yourself. https://www.simulation-argument.com/simulation.html

It's curious that the argument presented by Broston is not "it's likely that we're living in a simulation"; it's an either/or:

  Either we're living in a simulation, 
  OR an advanced civilization wouldn't be interested in running one. 
  (OR we won't become an advanced post-human civilization ourselves; 
  though that wouldn't prevent other species from running one).
Apparently too many people dismiss the second possibility and forget reporting about it when discussing the topic.

Also, the paper both assumes that galactic-wide computing power is physically possible, and that computing power is all it takes to generate civilization-deep simulations. I can think of several limits of physics and complexity that could make either hypothesis less than plausible, or at the very least, make option two (the post-humans not being interested in running such simulations) as likely as the "we're in a simulation" one.

>Apparently too many people dismiss the second possibility and forget reporting about it when discussing the topic.

I doubt most people even HN types have read the actual argument.

> I can think of several limits of physics and complexity that could make either hypothesis less than plausible

No one is saying this is feasible in the short term and no offense but I highly doubt that you are privy to the physics available to humans hundreds or thousands of years in the future.

I doubt the limits of physics themselves will change in the future :-P

There might be more knowledge on how to work around those limits to achieve efficiency closer to the theoretical limits. But to assume that a future civilization will have access to nearly infinite computing power (to the point of not caring about throwing several world-computers to a simulation side-problem), well, that's magical thinking.

I'm not saying that it can't happen. I'm saying that it's not the most likely possibility given our current understanding of how the universe works (which while not perfect, is quite a lot).

It all boils down to the first step in your version of the argument: if simulations are improving fast now, they will keep improving forever and reach any arbitrary level of power given enough time. It's the fallacy of infinite growth, ignoring the likely possibility of the growth process meeting some inner limits that will make it end.

I think you are seriously overestimating our current understanding of the universe/physics. For instance we don't even know if our universe is finite or not, if it's infinite then your point is moot and you literally would have access to infinite compute.

I disagree, I have seen research indicating that it's reasonable to have a computing system with on the order of 10^69 bits. There doesn't seem to be anything magical about this thinking at all. https://arxiv.org/pdf/1705.03394.pdf

By the same argument the people in the outer universe are in a simulation of the outer-outer universe and the people in the outer-outer universe are simulations in the outer-outer-outer universe, etc to infinity.

In other words the theory requires infinite complexity.

The argument says that there is a very high probability, not that it's for sure.

Who says that the simulation has to be done in realtime?

Without any outside reference the NPCs inside the simulation have no way to know that one second in the simulation has taken them for example a year in real-life.

It is not done in real time, it is done in relative time!

Elon Musk did respond to a similar question that you have asked here. The entire Universe need not be simulated at the same time. It could be a generative program. The reality could be limited to just what we are observing.

If you have enough resources to lazily simulate the entire observed universe, you probably have enough resources to consistently simulate the entire observable universe.

I haven't kept up with the latest out-of-universe hardware upgrades, so I could be talking out of my ass here.

With that said, why would you simulate something so ridiculously large and detailed if you only had the resources to run a small portion of it at a time? It's like buying an 8K 3D monitor and hoping your 3DFx Voodoo 2 will do the trick.

You might do this if you didn't have the computational power to simulate the thing you wanted in real time. Games are hard locked to require the computation to be performed within the frame time of the gameplay, but much more detailed and complex computations are done all the time to pregenerate an animated movie or video that can then be "played" in real time. The generation of the content often takes many times as long as the content actually is, but the purpose of doing it this way is to generate more detail per frame than you would be able to compute in the time between each frame when played at the ideal speed.

What is "real time", though? Time is relative within the universe itself, what hope is there that it even exists outside of it?

Using crude current metaphors: If I build a game, the concept of time within that game is, essentially, each tick of the game (a frame, for example, or a server-side tick). You can even have portions of the game world tick faster or slower relative to others.

But those ticks mean nothing outside of the game. Yes, in "real time" the ticks are constant... but I can pause the game at any point, it stops progressing. I can step it one tick forward, and for the game one tick has passed, but for me, any amount of time can pass.

In other words, there's no relation between time inside and outside the simulation, because it's a simulation.

Sorry if I was unclear, I didn't mean to imply a link between "real time" in the game/simulation and the real world, because you are completely correct in noting that there is no specific relation between game time (ticks) and "real" time (seconds or w/e units you want).

The link in the "time" that I am describing is one where the game graphics are rendered in 60 frames per second. If the computation cannot be completed within 1/60th of a second, the frame is delayed because it took too long to render.

My comment was largely in response to your assertion

"If you have enough resources to lazily simulate the entire observed universe, you probably have enough resources to consistently simulate the entire observable universe."

First, assuming that it requires less resources to "lazily" simulate something than to fully simulate it, then no, I do not believe that just because you can do the first means that you can 'probably' do the second. If you had enough resources for the first and not the second, but the first was good enough, why not do the first?

In response to: "With that said, why would you simulate something so ridiculously large and detailed if you only had the resources to run a small portion of it at a time? It's like buying an 8K 3D monitor and hoping your 3DFx Voodoo 2 will do the trick."

The reference to animation was largely in response to this, because that is exactly what the purpose of animation is. They have enough resources to render the animation in whatever length of time it takes to render, but they can't do it quickly enough to just render it frame by frame for the viewer.

I just realized I wanted to address this additional point:

> If you had enough resources for the first and not the second, but the first was good enough, why not do the first?

Why would you build something that is so immensely large, if you can only simulate a portion of it at a time? This hypothesis suggests that you would have to make the universe at least this large, or that lazy simulation is simpler.

Again thinking in terms of occam's razor and path of least resistance. It seems silly to make the unprovable theory even more complex and even harder to prove.

With that said I like Razengan's take on it; that is, c would be the speed at which the simulation computes new results (it also assumes the simulation isn't paused during computation).

Remember, even in simulation theory, there's nothing that suggests we humans are the intended product or object of observation; just like an ant farm that happens to be somewhere in some house in GTA5 isn't specifically the point of GTA5. So I wouldn't conflate "lazy loading" with "there are humans in this tiny corner of space, so we only need to simulate this tiny corner of space, and that makes a big difference in terms of computing power".

Re: lazy simulation

Would the fact that our “observable universe” is limited by the speed of light and time since “creation”, be a kind of a “lazy” simulation?

i.e. the “servers” that process us would never need to know about anything in the region that will never interact with us.

Ah, yes, I see where you're coming from.

My take on it is that it just fails occam's razor. As in, it turns the theory "The universe is a simulation", into "The universe is a simulation, and the simulation is imperfect and lazy-loaded". It's adding even more requirements to an unprovable theory.

Essentially, it turns "God exists" into "God exists, and he has a beard".

Ahhhh this makes more sense with your previous objections and I wasn't understanding it as well before. I always took little tidbits of the scenario that pointed to "lazy-eval" to be indicative of it being more likely to be a simulation because lazy eval is popular among programmers. Obviously when I write it out like that I can see where I lean on the same logic I argue against in other scenarios which is that we can't make any assumptions about intentions/motivations/etc. of the simulation creators, and the assertion that they would have similar programming paradigms is a pretty big assertion for sure.

>Is it actually possible to simulate the entire universe?

For you to be a simulation doesn't require the entire universe be simulated. It only requires simulation of you and the inputs you receive. Scale that and you can simulate a population to see how they react, all without needing to simulate every unobserved event to the finest detail.

It's how we can simulate all sorts of things now that relate to the physical world without having to simulate the physical world in it's entirety.

you need to simulate unobserved events when they are observed. I'm not looking at the Nile river right now but when I look at in again in 50 years it better look correct for the 50 years that passed. For it to look correct requires simulating everything about it, everything feeding into it, everything it affects, from the moment I stopped looking at it until I looked at it again.

>For it to look correct requires simulating everything about it, everything feeding into it, everything it affects, from the moment I stopped looking at it until I looked at it again.

No, it only needs to at the two points you take inputs provide answers that satisfy your understanding on what the inputs should be, and your understanding is formed by other inputs you've been fed, making the entire thing much easier. Satisfying you is probably much easier than satisfying someone who really studies rivers.

Neither you nor an expert needs simulating it much at all while you're not looking at it. And I doubt there's any case to simulate to any atomic or subatomic level. The gravitational pull of Neptune can likely be ignored. Neutrinos that may scatter from Antartic ice may hit it, but can probably ignored. And on and on. You're inspection is no where detailed enough to check if these things were taken into account for a decade while you were away. All of this detail is irrelevant.

It may well be possible to do a good job with a very rough simulation of water and time, all of which could be computed on demand.

So really all that needs stored is enough state to simulate in case you look at it again, and no work needs done on it between those looks. And this is a trivial amount of storage and computation to satisfy your two causal glances when compared to needing to simulate an entire universe down to all 10^120 subatomic particles.

I'm not sure what you said refutes his point. It still doesn't require the entire universe to be simulated.

If you observe the Nile, then yes it becomes an input, so that then would need to be simulated. This could take however long is necessary to do.

It still does not necessitate simulating the entire universe down to the minutiae.

Perhaps if the people in the simulation purposefully set out to "observe" somehow their entire universe in one timestep, in such way that _necessitates_ the complete simulation of their universe (like, say, running an experiment that involves all atoms interacting with all other atoms in their universe), then maybe it will be a problem. Then again, maybe the parent universe just has more atoms & computing power to throw at it, or it will generate a simulation that is "close enough" to the real thing that the people in the simulation will not be able to distinguish.

Please note how the simulated world in GTA5 is based not on atoms, but on entirely different concepts which allow modeling "large" amounts of in-world physics using a "small" amount of out-of-world atoms.

As long as we don't suppose that the simulated world copies all the features of the simulator-running world, there should not be a problem of needing more outer-world stuff to simulate a given amount of in-simulation stuff. They can just be quite different.

There's still an information-theoretic argument that the complexity of a simulated world cannot exceed the complexity of the outer "true real" simulator-running world. We still could see "more complex" activity of a simulated world by spending more "real" time to model "simulated" time, and having the simulated world to more often and more evenly fill various parts of its phase space, as opposed to the outer, simulator-running world.

> note how the simulated world in GTA5 is based not on atoms

That's actually my point. GTA5 doesn't work on atoms but the simulation of our actual universe would have to. Any NPC in our simulated universe can turn any building into rubble, turn any sand into glass, empty any lake, divert any river, put any drop of water under a microscope, mix any chemicals and watch their reactions, put any atoms in a particle accelerator, draw an animated stick figure with an electron microscope.

I'm arguing we can never simulate a universe because we'd need a computer larger than the entire universe to do it. I'm arguing that the thought experiment of "simulations will continue to get better until we can put A.I NPCs in a simulation of our universe and it will be impossible for them to tell the difference" is itself impossible.

The argument for why it's "likely" we are in a simulation is because it's argued it's inevitable we'll create such simulations ourselves. In doing that there will be more simulated people than not. It a huge assumption that "it's inevitable we'll create such simulations ourselves". If that is not inevitable then the likelihood we're in one drops dramatically.

A counter argument is we'll simulate a smaller universe for our NPCs but that argument doesn't really hold as it would argue that every universe is a simulation running in a larger universe to infinity. That would require infinite complexity

Why would a simulated being expect to see atoms in their universe? Their physical theories would be a result of whatever experiments they can do from where they're sitting.

What's so special about our physics that we would expect any possible consistent universe to be built this way? Maybe we're being simulated in a vastly different parent universe with more available computational power.

You're now basically saying "because magic!". Sure the outer universe could be based on something else but the thought experiment is that we'd be doing this in our universe. It doesn't require some other universe with magic unknown properties, it requires first that we can do this in our universe to a sufficient level that NPCs in simulations in our universe can't easily see the issues.

Sure, but why should we expect any 'host' universe to be based on such things as atoms, either? Perhaps our atoms are as coarse to them as models in gta are to us.

I don't think the argument depends on simulations being able to infinitely and recursively create sub-simulations. You only need one layer of simulations to make the odds work.

> Is it actually possible to simulate the entire universe?

In quantum mechanics there is something called collapse of wave function, which takes place when observer is making an observation on certain object. When there is no observer state goes into superposition which means it is one and zero at same time. So basically this means that object can exist and doesn't exist at same time.

That's why Einstein said he likes to think that moon exist even if no one is watching.

This looks similar to mechanism we use in rendering games today, you only load and render the view that players is looking at and the stage/level that player is in. Of course it's a lot more simplified in case of games. You can save resources using those methods while making huge scale simulations.

I wonder if by the time we solve a 'theory of everything' (or understand by some other means the basic mechanisms of our universe), we'll be able to efficiently, procedurally, generate a simulated universe.

Also, the Fermi paradox could be a solution - we don't see any other alien life forms because we're running in a computationally limited simulator, and everything outside our (relatively easy to simulate) solar system is running on minimum resolution (so to speak).

But we could simulate (in theory) a smaller universe than our own. Maybe that is what is happening. We can also simulate alternate physical properties. Maybe the simulating universe has vastly different rules/requirements.

Have you counted into your math that we're close (within 30 years I'd say) to more than 5 different computing revolutions?

to simulate our universe perfectly and in real time would take a computer the same mass as the universe.

> "As a huge bonus, Campbell claims the experiment could also explain the weird way that events in quantum physics seem to be influenced by the observer: It may be a quirk of the simulation we live in, not a fundamental aspect of reality."

I'm not a quantum physicist, but my spidey senses are tingling. Isn't this a common misrepresentation of a relatively well-known behavior in quantum mechanics, analogous to the Fourier transform trade-offs where a narrow window yields a poor resolution?

That's the Heisenberg Uncertainty Principle. He's talking about the observer effect, which is a different thing entirely. If you want some background on it, google the double slit experiment. This isn't an endorsement of Campbell's claims above, of course, just some clarity on what he's talking about.

You're talking about the Uncertainty Principle, which is indeed a property of all waves and not unique to Quantum Physics (I like to use the analogy of taking a single slice of a 44.1khz PWM data stream of an audio signal, in which you'd have 100% certainty of amplitude and 100% uncertainty of frequency. The more slices you take the more certain you are of frequency, less of amplitude.) Popular science and even QM itself has deeply confused itself on this issue over the past 100 years, yet it is as based in pure logic as the value of π is; nothing to do with the nature of the universe we happen to live in.

But they seem to be talking about the so-called Observer Effect, an even more deeply confused issue in QM. I'm not a physicist but from what I've read it can be understood as a quantum system becoming entangled with another system, the detector/observer, which causes the original system to lose coherence. But nothing magical is happening due to consciousness or whatever, it's just 2 or more systems interacting and interfering with each other. The trick is that "observation" of a quantum system is said to collapse the wave function into well defined values instead of probabilities. I think this is explained well by Quantum decoherence[1], that the isolated system acquires phases from its surrounding environment and thus loses it's original coherence and superposition, however the total system of observed and observer is still coherent (and I'm not totally clear on why the new system takes up well defined values for certain properties, but it seems to be some dynamical time evolved process especially when a small system interacts with a much bigger one, if you can follow the linked article).

And yes, I've heard these confusions combined into the notion that the universe only generates information when observed by some consciousness as some kind of space optimization, so maybe that is what the article is getting at.

Again, not a physicist, so I could be just as confused as everyone else, but I prefer to try to understand things these ways than trying to make sense of the constant refrain of dead and alive cats, the darkside of the moon not existing until we sent a probe to see it, and "you might be able to be in two places at once, just like a quantum particle!" we get from pop-sci and some grant seeking scientists.

[1] https://en.wikipedia.org/wiki/Quantum_decoherence

I was taught the ‘wave (eigenstate) collapse upon measurement’ concept, and in the lab, it’s just silly; the decoherence concept you describe is quite obviously the proper way to think about it, or we wouldn’t have to worry about losses from anything that wasn’t measured.

Simple explanation of QM: a classical object has a vector of properties, but in quantum this is a matrix. Any interaction is a matrix multiplication. After a bunch of matrix multiplications, you end up with a single eigenvalue, and now the quantum property matrix acts just like the classical property vector. The choice of linear operators, and probably the internal linearity among properties as well, is just a simplification, but otherwise we’d be mathematically lost in a world of functions that arbitrarily modify other functions.

Would love to hear answer to this from a quantum physicist. Any out there?

I recommend the book “Paradoxes in Probability Theory”, by William Eckhardt. It refutes a number of these thought experiments that play weird games with probabilities, including the Doomsday Argument and the Simulation Hypothesis.

I find its refutations convincing, although I could be wrong — there are many subtleties in play here.

Regardless, if you find the Simulation Hypothesis or Doomsday Argument convincing, you ought to consider these refutations. Intuitively, it should be surprising that we can predict the apocalypse, or deduce the nature of an infinite regress of simulated universes, just by sitting in a chair and doing some basic arithmetic.

I still think papers like these tend to undermine the sophistication and difficultly in solving the hard problem of consciousness. We can throw more and more computing power at creating a GTA-like simulation and make the AI more and more complex and ever more alive; but that won't ever make them conscious. And based on the current understanding, it seems that consciousness is more than just something that springs up from raw computing power. So the whole GTA-ification of reality just doesn't work for me. If we really are in GTA—well, why am I having the experience I am having?

Is that question even answerable?

> I still think papers like these tend to undermine the sophistication and difficultly in solving the hard problem of consciousness. We can throw more and more computing power at creating a GTA-like simulation and make the AI more and more complex and ever more alive; but that won't ever make them conscious.

You're assuming dualism from the start, and you won't get anything but more dualism out of this line of reasoning.

> If we really are in GTA—well, why am I having the experience I am having?

When the characters in GTA start asking themselves this out loud, you two can argue it over and one or the other of you will have an epiphany.

If our reality is built on top of a lattice, there’d be a fundamental coarseness to it, since there could be no details in our mock-universe smaller than the resolution of the simulation.

I'm pretty sure I read an article about some research team starting on exactly that project at least ten years ago. I may even have read about it on Slashdot.

Plank length?

I've said this before and I'll say it again. The problem with coming up with a test for being in a simulation is that the creator of the simulation might simply overwrite our memories. They could make us believe we succeeded in proving the simulation hypothesis false. There really isn't a way to test this properly when you aren't able to experience reality objectively. We're on the inside.

Side Note: I had an interesting debate just last night with some friends where I pointed out the creator of the universe might not even be aware of the aberration of our existence in it and from a high level thinks everything is running smoothly. And, we haven't made a big enough dent in the universe to get noticed. The question then becomes, if we for example destroyed a star or entire solar system to get the creator's attention would they go, "WHAT IS THIS?!" and delete the aberration? Contact us? Or, simply observe? Note: I was discussing a real god at the time, but my friend thought I was referring to a creator in the context of simulation theory at the time. Still an interesting brain buster either way.

Also, if it's true the creator is more of a macroscopic thinker than microscopic and are "asleep at the wheel" then it kind of explains a lot of things regarding injustices in the world. The creator just glances at the universe from time to time says to themselves, "Well, the galaxies are still spinning. All is well."

No offense to any religion. It was just a fun thought experiment.

Why should we be an aberration? Perhaps life is one of many things that occur naturally with relative frequency given the parameters of the simulation.

Most of humanity assumes we are meant to be here. It was a more interesting thought experiment to consider that we might be a happy accident.

"If there are long-lived technological civilizations in the universe, and if they run computer simulations ..."

This argument strikes me as similar in form to Fermi's Paradox -- and I don't buy that one, either. They both have the form: "If <unproven hypothesis 1> and <unproven hypothesis 2> and ... and <unproven hypothesis N>, then <surprising consequence>!"

In Fermi's case, the consequence is observably false, so people assume that (only?) one of the clauses must be false. In the Simulation case, the consequence is not easily observable, but the premises seem not-completely-outrageous, so people start picking away at it.

The hunch that "the universe is really really big, therefore occurrence X (which I just made up) ought to be happening an awful lot (but we have no way to even make a back-of-the-envelope calculation of how many times)" just doesn't hold water for me. There's plenty of cases where my planet seems really big, but things just don't happen as often as I might predict by looking at one corner of it. If something were happening all the time, it would have been happening all along, and you wouldn't need to come up with the idea just now -- obviously the only ideas left to invent today must not be happening much!

Apply the Fermi Paradox to the Simulation Hypothesis. The universe is only 14B years old, and AFAICT so far, completely void of intelligent life except for us (a very recent development). Isn't "life is exceptionally new and rare" a completely plausible (if boring) solution to both of these questions?

Fermi's just points out a contradiction between what's observable locally vs universally. So to your point can be related to simulation. But saying we're new or rare given how uniform it all is, is not boring but exceptional and that's the problem IMO. The fast radio bursts thing is interesting in this respect.

It's a possibility but I think not more likely than the possibility that we are not.

If we are, then it pushes back 'reality' one step back but the question of what 'reality' is remains. And that even opens new questions.

In my view this is similar the question of the origin of the Universe.

Both questions boil down to either a singularity or to infinity. It's difficult for the mind to make sense of either.

It is argued that there is a higher probability that we are living in a simulation.

It's not a very convincing argument because there's absolutely zero actual evidence to back the argument up, and absolutely zero reason to even accept the axioms the argument is based on.

He's arguing against that view and gave arguments. Do you have any?

The standard argument for simulation boils down to "in the future, we'll get access to insane computational ability, and someone is bound to run ancestor simulations just because we can; once this becomes possible, the amount of time consumed by such simulations will dwarf the time of history." In other words, the argument is basically "it's not impossible, so it will eventually happen, and over a long enough time period, it doesn't matter how long it takes to happen."

(As you might imagine, I am not persuaded by this argument.)

No, it's far more likely that we're the result of an emergency overload dump of a runaway thaumic reactor experiment run in the squash court of a university for wizards on a much more sensible flat world. There's far less hand-waving in that narrative.

How do you work out that probability?

There is only one "real" universe. If simulations are being run there's a potentially incomprehensible number of simulated universes. As a member of one of those universes, it is probable you are in one of the many simulations and not the only "real" universe.

That does not answer the question at all.

I suspect the simulation hypothesis is false. It relies on the premise that computers will get faster and faster until eventually we are simulating universes, but I suspect this will not be the case; we have been running into physical boundaries in making CPUs faster for quite some time. It's true that simulating a universe would lend itself well to parallelization in some respects, and it's also true that the universe would not have to be simulated in realtime in order for it's occupants to perceive it in realtime, but still it would be a monumentally expensive undertaking with current technology. Quantum computing may give us some big shortcuts here.

I also read a clever paper some years ago that assumed a minimum amount of energy required to perform a computation, and then asked, if our CPUs continue to double in power every year, how long will it be until we need to convert all the matter in the observable universe into its rest energy to power our computer? As with all numbers that double on a regular basis, the answer is shorter than you'd think.

But, there's a far more worrisome subset of the simulation hypothesis; when we train an image classifier, we show it a whole bunch of pictures of cats and dogs and "train" it. It stands to reason that when we want to build a general purpose AI, we will need to train it with general experiences. You could easily do that by recording a person's entire life and then feeding it to an AI. Hard to start recording a person right out of the womb, but you could make some minor modifications to the recording so that everyone in this "recorded universe" thought it was perfectly normal for everyone to not remember the first four of five years of their life.

If this hypothesis is true, then I have good news; when you "die", there will indeed be an afterlife. There will be several in fact, as you are instanced across many servers and put into service doing natural language processing for users of the iPhone MMLX.

I remember my philosophy teacher saying to the class that we can make 3 hypothesis:

- Technology can advance until we can make simulation undicernable from reality: in this case, we are likely to live in this simulation

- Any civilisation comming close to the previous point is likely to already have destroyed itself. In this case, living in a similation is unlikely,

- Technology can't advance to this point in our universe. Living in a simulation is impossible.

On of these proposition is true, but we are unable to know which one. So we have to put an equal weight on those, and the probability that we live in a simulation is 1/3.

Sadly (or hopefully), Church-Turing conjecture is somehow backing the 3rd theory too, and i'll by anything coming from Turing.

It is fundamentally impossible to know whether we live in a "simulation". The concept itself is a notion connected to contemporary culture based on certain technical knowledge, and thus the definition of what a simulation is isn't absolute, but rather subjective.

It follows that not much objective can come from this biased root assumptions.

In many ways physics is theoretical nowadays. You can look through the list of theories in theoretical physics and realize that it is all a giant construct. Physicists can spend their entire careers with illusions, which is ironic as physics supposedely is about reality.

At the end of his career, Albert Einstein said:

"I think it's entirely possible that physics can't be based upon the field concept, i.e. consistent structures. In this case not a single part of my cloud-castle remains, including the theory of gravitation and all the rest of modern physics."

Wouldn't the world view of a single god who created the universe also fall under a "simulation"?

The simulation won't allow it. Those trying to determine it will be eliminated from the simulation. Even discussing this on a public forum is dangerous.

From the observation that miracles and divine interventions, widely reported earlier, are all but gone for many centuries, we can conclude that the simulation is now considered production-quality, and live-patching via the debugger interface is no more practiced.

If this is true, then the fact that no one is eliminated after this discussion would be evidence that we're not in a simulation. At least not one with the rules you suggest.

But maybe the simulation does allow such discussions.

We probably don't remember those who were eliminated.

who brought this up anyway?

Or maybe the ones running the simulation don't have good tools to check the logs, and have not yet found out.

I think those scientists should hire the researchers who keep discovering escapes from VMs/containers. Depending on which iteration we're on, there might be some simple low-hanging fruit like a BIOS call we could make. ;)

Aside: read "Microcosmic God" [1], an interesting sci-fi short story by Theodore Sturgeon [2].

[1] http://1pezeshk.com/wp-content/pics/2013/01/microcosmicgodth...

[2] https://en.wikipedia.org/wiki/Microcosmic_God

Science can never "prove" a hypothesis - it can only disprove it. Therefore, a hypothesis that makes no falsifiable predictions has no business in scientific discourse. This is a point that non-scientists (and, unfortunately even some scientists) often get wrong.

Some on this thread have compared the simulation hypothesis (SH) to theology. The difference is that the SH, at least in its most useful form, makes falsifiable predictions, as shown in the article.

Theology, on the other hand, makes no falsifiable predictions. Christian theology takes this one step further by elevating "faith" to the highest plane of human being. Reason and disbelief, Christian theologies tell us, is the path to pride and Satan.

If you think you're living in a simulation, maybe you're projecting something about about your cushioned (alienated) consumer lifestyle onto life itself. Your been absolved (robbed) of contact with the roots of your life. You sit in comfort zones, nibbling and sipping on life's material fruits, discarding packaging to the netherworld, wondering if the roots ever even ever existed in the first place. You're starting to doubt it. Maybe you're just living in a simulation.

I'm more interested in this idea as a product of contemporary materialism than as a testable physical theory.

Study semiotics, then ask yourself again if you're living in a "simulation".

Hmm, I mentioned in another comment that I'm not even sure how much I "believe" this premise, but for the sake of discussion let's assume I do as I find it fun to think about from time to time.

Your post sounds very condescending, but I'm interested in what sounds like a completely different take on the topic than I've seen before. I don't know anything about semiotics and had to look up what the term meant before posting. What would be your abbreviated and distilled thesis for how semiotics relates to this topic and to your first paragraph? Phrase differently, if I were to study semiotics, what part of it in particular would be the most relevant to changing my answer/ideas related to the question "am I living in a simulation"?

I had a math teacher in high school (Mr Atlas) that asked an epistemological question: “What if, before Copernicus, the stars really were just holes in the sky?”

Think of scientists as unit testers for new features in CI.

If we're in a simulation, it's almost certainly not a computer simulation, but some technology that we can't even imagine, any more than cavemen could imagine computers.

Infinite 2-state, 3-color Turing machine.

It's absurd to think that any entity within a simulation could draw conclusions about anything outside the simulation itself.

"Better than 50%" my ass, Elon and Neil are hacks.

The probabilistic argument can be made the other way:

All the information for a simulated universe needs to be stored in some form in the outer universe, but the outer universe would also contain information not used for simulation.

If we consider an arbitrary piece of information, chances are it exists in the outer universe only - unless more than 50% of the outer universe is used for simulations.

If 100% of the outer universe is used for simulations, than the simulations are the outer universe(s).

If this is a simulation then it’s pretty mundane. If civilisations had the power to simulate universes, i can imagine vast numbers of more extreme or interesting universes. Heavens, hells, dramatic and artistic experiments. The mediocrity principle coupled with the fact that we’re in quite a boring universe seems to indicate that either the majority of simulations are quite mundane for some reason, or we’re likely not in a simulation.

Given the immense size of our simulation and our relatively small presence in it, it could be that the simulators had no expectations of it becoming self-aware. It would seem that they simply picked some fundamental parameters (physics) and started it.

How do you know this universe is boring / mundane to a hereto unknown creator civilization? Maybe this universe is highly novel when compared to their experience?

Maybe we are being simulated by a benevolent super-being playing The Sims

I don't see it as any more likely than us not being in a simulation. Regardless, these discussions always drag up so much existential dread in me.

I like the moral implications: if the existential risk is being shut off, we should all do our part to keep things interesting

Slightly off topic, but anybody who's interested in thinking about the simulation hypothesis might get a kick out of this short fiction piece: https://scifi.stackexchange.com/a/166941

One of the most important worries and cause of anxiety I have had, has been the question of who created humans and why. And who has the created this entity in return and who created that entity in return, so on and so forth.

I had many panic attacks with a sense of futility to life and meaning of it. Until some years earlier, I had an insight that maybe the rule that everything requires a beginning is a necessity for human mind to comprehend things. It is very damn well, possible to have things to exists without anyone setting things in order.

There is a significant probability that this world simply exists without a beginning nor an end. This notion has given peace and satisfaction & I very well maybe wrong, but that is least of my concern now.


"We"? Down this line of thinking, maybe the rest of you don't exist. Maybe I made the simulation complete with friends and then erased the fact from my memory.

Maybe instead of bugs in the simulation we should be looking for design flaws like irrational numbers for constants or slews of arbitrary particles. Of course if the universe were well designed we could use that as proof it's a simulation too.

But I'm not sure "fun to think about" corresponds with "interesting enough to take even remotely seriously"

Of course "Are we living in a simulation" is far too vague to test. The type of simulation must be narrowed down before the question can be tested.

In my paper "A type of simulation which some experimental evidence suggests we don't live in", I give an example of a (very specific) type of simulation which we can easily test: https://philpapers.org/archive/ALEATO-6.pdf

Side note: I strongly believe that we’re just living inside a dream of some billionaires that were completely bored out. And, there is no test to falsify that thought...

I always thought that one of the biggest criteria for the existence of a “parent” “reality” would be whether there is such a thing as Free Will or not.

If there is true randomness in our universe, then surely it must come from outside the universe, or our system could spontaneously put itself into an invalid state at some point and possibly crash, no?

How would you tell if a competent simulation was fixing the results to return "I'm not a simulation" when queried?

If there are simulators, can't / won't they detect our attempts to test the simulation hypothesis and patch any defects that scientists might notice to render such experiments un-reproducible?

Unless they really want us to find them. But then there are easier ways for that. One is simply painting in the sky: show me what you got.

Aliens might not be constantly watching all billions of life forms. Aliens might not care if we find them or not. There's plenty of reasons aliens wouldn't bother to interfere.

If you buy the Simulation Hypothesis, based on the premise that aliens have infinite computing power in which to run simulations like this, then logically you should also believe that we're not special. With infinite computing power, they don't need a giant datacenter and a research team to run us. It's just a few basic principles they chose last month (in their time), and a little box sitting on someone's desk, like the TNG episode "Ship in a Bottle". With infinite power, there's probably millions of simulations running.

Maybe if it becomes self-aware, a light turns on, and they cheer, like we do when the bouncing DVD logo hits exactly in the corner -- and then they go on with their life. Maybe kids pick different initial conditions and race to see which universe becomes self-aware first.

I don't believe the Simulation Hypothesis, but if it is true, the most likely scenario is that there's gobs of different simulations running, and aliens don't care about us at all.

This assumes that there exist some "they" who "set up" the simulation and are "watching" it. It's an excessively strong assumption, to my mind.

E.g. known biological life critically depends on an implementation of a machine programmed by DNA, but there's little doubt that said machine was not specifically engineered for the purpose by anyone.

It's not a trivial task - think about how hard it is to detect computer viruses in a computer.

Then we also know that homomorphic encryption is possible in principle, where from the outside it's thought to be impossible to figure out what computation goes on inside the algorithm (for example searching for a simulation)

Maybe something like conways game of life but using rules of thermodynamics instead to distribute cell energies may be fruitful at even a small level? Also it's worth considering if a reality that can operate outside of, or break mathematics/physics is possible. i.e. 1/0 as this would be harder to simulate

Here is my collection of thoughts and opinions on the topic.

First: The fascination for simulation hypothesis is another extension of us humans wanting to be something special and also being very worried that we might not be so special after all. This is the constant inner battle of our minds between the our inferiority complex and the mediocrity principle. Like as if living a simulated but enjoyable life is not good enough. But, that is not to say that it is not at least an interesting thought experiment everybody should try once. It can even help us understand our own insignificance. (Excuse me, my nihilist got out)

Second: I do think there is no such a thing as simulation or even an inner and an outer forming a hierarchy. Imagine two astronomers looking into a telescope. One says to the other: "Wow, look I created this galaxy in there. And if I change the parameters just so slightly by adjusting this here, I get a totally different one which still has some similarities to the last one." Now, replace the telescope by a computer screen and the astronomers by two people programming a video game. What they fail to realize is that they do not "create" these galaxies or simulated universes. No, they are just observing them. And by interacting with the computer you don't change the simulation but instead switch to observing a different version. But, just like the natural numbers all of this just exists. It does not come into existence (is not created), neither does it cease to exist or change. It also needs no space or memory to be stored on and no mass to be conserved. 1+1=2 is true with and without us. It is completely independent. Concepts like time, space and mass are specific to some universes (like ours) and are not universal (pun intended).

Third: Yes, multiverse theory does not solve everything, but it solves the "trivial" questions like: - Are we the result of an intelligent design, god, alien, simulation? Question which are just offsetting the problem by one. - Are we just a computer simulation and thus not "real"? All universes are equally real, there is no hierarchy: Cognito ergo sum. - Can we break out? Everything you find would just be another physical law and property of our universe. Or you get really lucky and are actually boltzmann-brained, allowing you to visit another universe while keeping your memories of the last one. At least that is what it would seem like to you.

Yet, multiverse theory lets us move on to the harder questions like: Why does anything exist at all? Wouldn't it be much simpler for just nothing to exist? What is qualia and how does it "emerge"?

P.S: Let them do their experiments, maybe they accidentally find something useful anyways.

surprised no one has mentioned The Fabric of Reality by David Deutsch. it's a must read on the subject, in particular when it comes to all the irreducible hints and theoretical constraints that would allow us to rule out a simulated reality.

This is more or less simply impossible. If we observe some fact X about our universe we have no source of truth that can tell us whether X should be true or false for real universes, simulated universes, or both kinds of universes.

It's impossible to prove, but empirical evidence could improve the theory.

What kind of evidence are you hoping for? Say we measure particle trajectories very precisely and discover something that looks a lot like floating point rounding errors. Now what? How would you know that the physics of the real universe doesn't resembles floating point numbers? It is absolutely unjustified to jump from the universe looks smooth to us but our computer simulations have finite precision to the real universe is smooth and simulated universes might have finite precision.

It is an attempt to distinguish something we don't know from something else we don't know. Everything we know about our universe might be something that applies to real universes or something that applies to simulated universes depending on whether we live in a real universe or in a simulated universe. Even worse, we know nothing at all about simulated universes if we live in a real universe and we know nothing at all about real universes if we live in a simulated universe.

Even if detecting that we are/are not in a simulation, building experiments to help answer unusual questions is another way to understand the physics of our reality. I think it is great.

Where is all this computing power coming from? How many universes could you compute with the power of one sun over the course of it's life?

Why only one star? Even if you assume the simulating universe has similar physics to ours the simulating entities could be Kardashev[0] III, IV or V


Eh, dark matter is the bug they seek.

I hypothesize that its one or a combination of these three things.

1. these people have run out of research ideas.

2. they want a series on the Discovery network.

3. they are scamming gullible billionaires into funding the "research".

The fact that Tyson has something insightful to say makes point 2 a strong possibility, I say better than 50-50. I am disappointed to not see Kaku pitch in.

And 4. They watched The Matrix at an impressionable age.

Couldn't a simulation also simulate our conclusions that we are not in one? It doesn't seem like one could answer this with any certainty in the end.

If its a simulation there would be some "shortcut" way to get into "root" or supervisor mode.

Why? Conway's Life doesn't have a supervisor shortcut.

Depends how you think about it.

What if you ran Conway's Life simulation, and suddenly on you screen appear cells ordered in the form of text messages like "Hi, I am aware that this is a simulation, I want to talk with the entities outside it".

Conway's Life is a mathematical concept. Actual programs: 1- can have bugs. 2- could have backdoors.

For example, if you have more than 1024 live cells, there could be a buffer overflow that would be seen in the Live universe as a magical doorway from which gliders could come or go.

You could implement a backdoor: a small area where spiners would send a message to an external process, perhaps yourself, and that would influence the rest of the game.

And as the God of your Conway Life, you can add live cells or kill them by the mere touch of your finger on the touch screen! What more do you want?

Applications are open for YC Summer 2019

Guidelines | FAQ | Support | API | Security | Lists | Bookmarklet | Legal | Apply to YC | Contact