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Re:The Universe Is Not a Simulation, but We Can Now Simulate It by nothis on Wednesday June 27, 2018 @03:29PM (#17411047)
Is the "Universe is a Simulation" more than a dreamy internet theory, though? Like, are astronomers and physicists taking it seriously? I don't know either way, I just assumed the headline was basically saying "no, this isn't some sensational new post about how we're all in a simulation, this is hard data leading to realistic results". Kinda defensive more so than click-bait-y.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by beefield on Wednesday June 27, 2018 @03:41PM (#17411147)
> Is the "Universe is a Simulation" more than a dreamy internet theory, though? Like, are astronomers and physicists taking it seriously?

There is no practical way to falsify that so yes, it is just a dreamy theory.

Unlike some other dreamy theories (creationism and astrology come to my mind) nobody has come up with any practical uses for the dreamy theory either, so that would be a second reason why nobody takes this dreamy theory that seriously.

But if this is a simulated game, I would be keen to know how this is scored and how many lifes I have left before game over...

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by ghostbrainalpha on Wednesday June 27, 2018 @04:14PM (#17411446)
Considering that you don't know this already... if the Universe is a Simulated Video Game its very unlikely that it was created for you to play.

It's much more likely that you are just an NPC waiting to be harvested for some aliens experience points.

The most you can hope for is that you are destroyed in an interesting way, and perhaps your memory lives on in a highlight reel on that aliens stream.

I've often wondered if God existed at one point and we were just his video game. But now God found a more interesting game to play and we are just a forgotten game in chugging along in his steam account. I don't think there is a better explanation for the miracle of the pyramids, or the invention of magnets.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by beefield on Wednesday June 27, 2018 @04:28PM (#17411563)
> Considering that you don't know this already... if the Universe is a Simulated Video Game its very unlikely that it was created for you to play.

Well, if I think from bayesian point of view, given that only creature here that I personally can be somewhat confident actually having any sentience happens to be me, then it would feel quite likely me being a player. Especially as this can be single player game as well...

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by ghostbrainalpha on Wednesday June 27, 2018 @06:01PM (#17412216)
I think you are saying that it would be cruel to create a game where the scenery has real consciousness or sentience.

But just because something could be cruel doesn't make it less likely. I think we are basically talking about the plot of West World. And pointing out that it doesn't make sense to give an active inner life to characters that exist only to fill out someone else's designed game experience.

But just think about it. If Sims 2099 is capable of giving consciousness to its characters, or at least something so much like it that the characters believe the are conscious, don't you think its very likely players will ask for it? Regardless of the ethical implications.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by rf15 on Wednesday June 27, 2018 @04:17PM (#17411469)
I guess that last paragraph shows the temptation, our wish for meaning and some meta mechanism around us beyond a couple of rocks we can see flying around. We are unable to deal with the concrete mundanity of reality. (learning how things work is fascinating, but watching most processes for a prolonged amount of time is... not)
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by cortic on Wednesday June 27, 2018 @04:28PM (#17411562)
There are a few scientific reasons to believe that the universe is simulated;

One has something to do with the information in black-holes, i can't remember the details but it suggested to me that '3d space' was fundamentally artificial.

Another has to do with quantum entanglement, the explanation for spooky action at a distance could be that the two particles are still in the same 'bit of memory'.

And lastly the Uncertainty principle is thought to act a lot like an on-the-fly loading frame in an RPG.. As silly as that sounds there is not really a satisfying explanation of why things are less certain when we are not interacting with them.

Its worth noting that even if the universe is simulated, it might not be simulated by intelligence, we don't know enough to say its not 'naturally simulated', that might seem paradoxical but 'simulated' and 'artificial' are very loaded words; A reflection of the moon in a pond is in some way an artificial simulation of a moon..

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Wednesday June 27, 2018 @03:37PM (#17411124)
I don't think any scientist should take it seriously. It is at the level of "maybe this is all just a dream". Well perhaps, but we have no way of knowing. It is an unfalsifiable hypothesis so it is outside the scope of science.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by strange_quark on Wednesday June 27, 2018 @04:17PM (#17411467)
It's basically religion but with none of the morality attached to it. No wonder so many SV billionaires like the idea.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Thursday June 28, 2018 @09:43AM (#17416761)
So like "the singularity" and "transhumanism" - millennia-old religious ideas, repackaged for a technological age.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by jerf on Wednesday June 27, 2018 @03:41PM (#17411149)
Yes, it is a serious theory, taken seriously by serious scientists, and seriously investigated by them.

It can be hard to tell through the popular science stories, where the author is typically unable to relay anything about this research without adding "woo woo" sounds and wiggling their fingers, but it's a real theory.

One thing that may be worth remembering is that in the real theory, the "simulation" is not necessarily running on "a supercomputer just like what we have, only way bigger", which is actually a silly idea for various reasons, and we also do not know that the simulation is literally simulating every particle and every cubic inch of space in the most accurate possible way (i.e., for all we know, far away galaxies could just be a few megabytes in size, rather than fully simulated to the nth degree). The "Great Simulator" is not required to run anything remotely resembling our physics. What seems an absurdly large computation may be smaller than it appears, and may not be an absurdly large amount of a universe running on fundamentally different physics.

(Occasionally when I'm bored, I noodle around with a theory of cellular automata in which the universe has infinite computation power by virtue of being able to split a cell in half or quarters, that then runs at double-speed relative to the outside. If this is done recursively the universe has arbitrary computation abilities relative to the "top level". I've never worked it into anything usable, but I think it can give a flavor of why we should not be sure that our simulation host is necessarily as staggered by the computation as we would be. We are not even capable of saying that they aren't running an exponentially-expensive quantum approximation algorithm with the entire universe actually arbitrary-precision integers under the hood. The staggering amount of computation that represents may not bother them at all.)

It is not a theory that is, strictly speaking, falsifiable thanks to Church-Turing equivalence, but there are ways in which it could potentially (to any arbitrary degree of confidence you may want) be confirmed if it is true. To take one degenerate case, if the Great Simulator broke silence and starting wildly breaking the laws of physics to get our attention, that would certainly put a lot of probability mass on the "we're a simulation" theory. There are less extreme cases we could conceivably pick up on, that just fits into an HN comment nicely.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by whatshisface on Wednesday June 27, 2018 @03:49PM (#17411231)
>It is not a theory that is, strictly speaking, falsifiable, but there are ways in which it could potentially be confirmed if it is true.

It's worth noting that most religions are in exactly the same situation.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by madaxe_again on Wednesday June 27, 2018 @04:00PM (#17411319)
The great simulator doesn’t even need to be great. It only needs to be good enough to simulate heavily time-dilated reality for one individual. A highly detailed, highly realistic first person game only needs to simulate the immediate draw of the player character to be useful - you don’t have to draw every NPC’s worldview - they just need basic path finding, at best.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by perl4ever on Thursday June 28, 2018 @08:45AM (#17416372)
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by om3n on Wednesday June 27, 2018 @04:11PM (#17411414)
You are referencing solipsism: https://en.wikipedia.org/wiki/Solipsism
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by madaxe_again on Wednesday June 27, 2018 @05:29PM (#17412004)
I’m well aware of solipsism, but there’s nothing to say that a convincing simulation couldn’t be purely solipsistic.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by thraway180306 on Wednesday June 27, 2018 @04:41PM (#17411674)
Of course it is falsifiable. If you can't specify in what way you recover physics from your simulation and what computation actually occurs in your simulation then, apart from the word "simulation" making no sense, you don't have any theory to either formulate or test at all. There, falsified for you. In particular cellular automata fit that description. It has been beaten to death since the 80's and leads nowhere, unless of course anybody counts Wolfram a (new kind of) scientist.

Same problem we have in quantum gravity. We just can't recover known physics from anything at all, any combination of theories at all it seems. That includes all known instances of computation, it just blows up.

Also, Church-Turing has nothing to do with basic problems here, in particular because eventual simulating computation would be unlike computation we know (which again, makes the word lose any meaning here).

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Wednesday June 27, 2018 @05:04PM (#17411856)
That is not what falsifiable means. Falsifiable means that an experiment can be devised which could result in observations which contradict the predictions of the theory.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by thraway180306 on Wednesday June 27, 2018 @05:37PM (#17412039)
Falsification is a philosophical issue. Some say it's important. Some could live without. See Feyerabend.

None of that matter if there is no theory in the first place. Much was tried. 't Hooft got as far as holographic principle. And there's still no theory at all.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Wednesday June 27, 2018 @03:49PM (#17411223)
> It is not a theory that is, strictly speaking, falsifiable,

So in what ways is it a "serious theory"?

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by jerf on Wednesday June 27, 2018 @03:56PM (#17411291)
Well, along with the religion case that whatshisface points out, there's also the problem that any theory of the nature of the universe has this problem. The problem here is not with the theory of the universe per se, but the fundamental limits of science itself.

Despite what seems to be a popular opinion, we are not actually obligated to curl up into a ball on the floor and cry about our inability to know anything just because science can't be definitive on some point. We just need to be aware of the limits of our knowledge. We have no choice; even in just our day-to-day lives, we are required to make all kinds of decisions for which science is either quiet, insufficiently informative, or (and this one may really hurt to think about too much) simply wrong.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Wednesday June 27, 2018 @04:39PM (#17411647)
> Despite what seems to be a popular opinion, we are not actually obligated to curl up into a ball on the floor and cry about our inability to know anything

I have no idea what you are referring to here. Can you be bit more specific about what viewpoint or philosophy you are satirizing?

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by da_chicken on Wednesday June 27, 2018 @04:31PM (#17411588)
Well, it's a little more complicated than that. It's only not falsifiable because nobody has devised a test. It's a hypothesis without an experiment. That doesn't mean that people aren't trying [0]. If it is a simulation, you're not going to clip through the wall by running against a corner and jumping for an hour.

The thing is, we don't know where this line of reasoning would even lead. I mean, people used to think that light had to travel in little packets through luminiferous aether [1] and look where that investigation led: Einstein, special relativity, atomic weapons and power, nuclear medicine, etc.

Let's say the universe is fundamentally indistinguishable from a computer simulation. What consequences does that have? What does that say about the types of math that can be used to describe the universe? Or, perhaps better, the types of math that shouldn't be used to describe the universe? What does that say about our ability to model a portion of the universe and therefore predict outcomes? Does it have implications for stochastic processes? Indeed, where is the stochasticism coming from? Is everything predictable or is there some fundamental randomness?

On the other hand, what if we can show that the universe is distinguishable from a computer simulation. What does that mean for our understanding of the universe as it exists? Does it reveal a fundamental aspect of reality that we have missed, or a limitation of our mathematics, or a fault in our computer models or design, etc.? We're dogs learning calculus here, and the universe isn't obligated to make sense.

Even if we can never find a useful test for this hypothesis, the line of thinking itself potentially leads us into new areas of discovery.

[0]: https://gizmodo.com/5950832/how-to-tell-if-the-universe-is-a...

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

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Wednesday June 27, 2018 @04:49PM (#17411738)
The problem is...you can even define what it means for the universe to be a simulation. You might as well argue like George Berkely that all sensations are signs and symbols directly from God - it is not even wrong. It is fundamentally unknowable - unless God or The Simulator choose to reveal themselves directly to us.

The luminiferous ether was a falsifiable theory - indeed it was a breakthrough for physics because it was falsified (experiments failed to detect it) so new theories had to be developed. So this is completely different from unfalsifiable metaphysics.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by da_chicken on Friday June 29, 2018 @02:32PM (#17426549)
> The luminiferous ether was a falsifiable theory

But it effectively wasn't for the first 150 years of it's existence. The theory originated in 1720 and it wasn't disproven until 1887. It took that long for someone to come up with a conclusive experiment. Nevertheless, for those 150 years the luminiferous ether theory was widely held, shaped the field of physics, and the research had to go into finding an experiment to test the theory.

Similarly, the idea that atoms might do things when high energy particles hit them was all theory until Wilson's cloud chamber became the first particle detector and suddenly physicists could see what these particles were doing when they hit things.

> The problem is...you can even define what it means for the universe to be a simulation.

You're confusing something that hasn't been done with something that can't be done. Indeed, what they're trying to do is exactly trying to define criteria to test that the universe is a simulation. It's the first day of school and you're complaining that Newton doesn't have his Principia and Gilbert doesn't have his De Magnete.

Theories often predate the knowledge of how to test them. This isn't weird.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Wednesday July 04, 2018 @05:58AM (#17456251)
In order for a theory to be falsifiable it first have to be a theory! The simulation hypothesis is not even a theory (i.e. it makes no verifiable predictions), so it is not even falsifiable in principle.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by freeloop10 on Wednesday June 27, 2018 @09:57PM (#17413494)
It is falsifiable if you consider that a simulation would have limited resources allocated to it. The null hypothesis would be the universe runs in a way where a simulation couldn't cheat by performing a rough calculation at the hard parts, thereby spending a tiny fraction of what would be needed and produce the same observable result.

The idea that quantum fields exist in multiple states simultaneously until observed become evidence for a simulation, since a simulator could be deferring calculations on things not observed.

Also, the very program this article is referring to could be considered as evidence for it, since if a rough simulation can be made where the observable result is indistinguishable from a result where every atomic element in the entire universe was simulated, then, again, a simulator with limited resources would make do.

The law of conservation of energy is built the same way. There is no way we can test ways that energy is transferred that we don't yet know about, but this law is still considered true, because we have so many examples of it working.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Thursday June 28, 2018 @01:39AM (#17414350)
Well I guess you can disprove particular forms of simulation - e.g. since a computer with 16GB RAM can be adequately simulated, we can reject the notion that the current universe is simulated on a computer with 16GB RAM or less.

> The idea that quantum fields exist in multiple states simultaneously until observed become evidence for a simulation,

How is that evidence? Current physics can model that without relying on a simulation hypothesis. Adding a simulation hypothesis does not simplify the model, and it is unfalsifiable.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by freeloop10 on Thursday June 28, 2018 @03:45AM (#17414860)
Why did you quote half my sentence, leaving out the part where I explain why, and then ask why?

> Adding a simulation hypothesis does not simplify the model, and it is unfalsifiable.

I explain this. It's falsifiable if it can be shown there is some extremely large and complicated process that be observed to be different than any possible rough calculation that could be accomplished by a simulator with very constrained resources (constrained in comparison to all the supposed atomic particles in the universe)

The notion that all forms of energy must be conserved, even undiscovered ones, has been used as the basis for the theory of Hawking radiation, isn't it? Yet claiming that undiscovered forms of energy are conserved, just as known ones, is unfalsifiable, too.

The law of conservation of energy, including undiscovered ones, is in the same boat as the theory that the universe is a simulation.

Until we find a form of energy that isn't conserved, it is simpler to assume all types of energy are conserved.

Similarly, until we find a process that is of large enough scale that it couldn't be simulated on a computer with resources much more limited than the size of the universe, and be observable identical to a process taking much more resources, it is simpler to assume it all is being simulated in such a way.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Thursday June 28, 2018 @04:39AM (#17415105)
> Why did you quote half my sentence, leaving out the part where I explain why, and then ask why?

Sorry I just didn't want to quote the whole comment, didn't mean to imply I was only responding to the first part of the sentence.

I understand you can hypothetically prove that a simulation of the universe would require a simulation engine of at least a certain complexity. But since the simulation engine does not exist in this universe, we have no idea about what limitations or laws of nature (if any) it is subject to. You will never be able to prove or disprove the existence if this hypothetical simulator.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by freeloop10 on Thursday June 28, 2018 @08:16AM (#17416222)
Well, a Turing complete computer is about as abstract as you can get, and so is the concept of memory, regardless of the natural laws of some outer universe, it'd probably be a good starting point to consider a turing computer except with limited memory.

The point is not to prove one way or another whether the universe is a simulation, just like there is no point trying to prove the law of conservation of energy as universal for all forms of phenomena, discovered and undiscovered.

It's just if we can show that all known phenomena can be the result of a very limited simulation, then when analyzing new phenomena, we can also expect it to be runnable on a very limited simulation, too.

It's the same as assuming that the law of conservation of energy would apply to any new phenomena we discover. There is no proof, but it's a good starting point.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Friday June 29, 2018 @01:49AM (#17422662)
You cannot through experiments prove that the law of conservation of energy holds in all cases. Indeed you cannot through observation prove that any law of nature holds in all cases. But you only need a single counterexample to show that a law doesn't hold in all cases. This is exactly the rationale behind the principle of falsification. You cannot prove through observation that all swans are white. But you can prove that not all swans are white by a single observation of a black swan.

The bottom line is that it is possible to devise experiments or observations which would give different outcome if the theory holds and if the theory doesn't hold.

But you cannot devise an experiment which would give different outcomes if the universe is a simulation versus if it isn't. More specifically, you cannot imagine an observation which would prove that the universe isn't a simulation. Therefore it is not a legitimate scientific theory. At best it is a fun thought experiment.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by freeloop10 on Friday June 29, 2018 @02:43AM (#17422848)
> But you cannot devise an experiment which would give different outcomes if the universe is a simulation versus if it isn't.

I've already mentioned 5 times in this thread that the theory I'm talking about is of a simulation with very limited resources, but you seem to be ignoring this point.

Show that a particular phenomenon can't be simulated using extremely limited hardware (compared to the size of the universe) and you can falsify this theory.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by olavk on Friday June 29, 2018 @08:03AM (#17423985)
I didn't ignore that, I mentionend the "limited resources" scenario with the 16GB example a few posts back.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by freeloop10 on Friday June 29, 2018 @02:56PM (#17426782)
> But you cannot devise an experiment which would give different outcomes if the universe is a simulation versus if it isn't.

Does this or does this not apply to a simulation with very limited resources (compared to what it would take to model all the atoms of the universe) or not, then?

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by rbanffy on Wednesday June 27, 2018 @04:16PM (#17411454)
> So in what ways is it a "serious theory"?

People defend it with a straight face?

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by samirillian on Wednesday June 27, 2018 @04:05PM (#17411347)
Wait, why isn't it falsifiable?

Edit, oh, duh.

Yeah, my main take is that there should be evidence for it being a simulation, and in lieu of said evidence it should be assumed untrue

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by qubax on Wednesday June 27, 2018 @03:58PM (#17411299)
> Is the "Universe is a Simulation" more than a dreamy internet theory, though?

It's a theory that predates the internet. In the expanded view, the theory goes back to antiquity.

The modern version is a thought experiment more in line with the drake equation than a dreamy internet theory. It's an idea born of some assumptions and mathematics.

> Like, are astronomers and physicists taking it seriously?

Some are, most aren't. But then again, most astronomers and physicists don't take SETI seriously as they have their own work to focus on. But it certainly isn't anything to be dismissed just like the drake equation or SETI.

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by sandworm101 on Wednesday June 27, 2018 @03:37PM (#17411121)
It is the internet misinterpreting some perfectly valid scientific investigations. A rational discussion of quanta and quantization, how observable information is coded in our universe, morphs into talk of whether that universe actually exists inside a big computer. To correct such rants one must explain quantum physics, something nobody wants to do anytime soon. It made for a half-decent Doctor Who episode.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by ben509 on Wednesday June 27, 2018 @04:41PM (#17411669)
The one-electron universe[1] was also a dreamy theory, but it inspired some groundbreaking ideas in quantum mechanics.

I think the universe as a simulation is less interesting as it's really just taking the notion of materialism to its logical extent. But in fairness to it, it's now part of culture, so if it's causing us to think in ways we wouldn't be aware of, it's harder to see it influencing someone than if he's Feynman getting a sudden phone call from Wheeler.

Many thought experiments can also be useful insights into nature of things. The idea of a Boltzmann brain[2], for instance, challenges your intuitions of infinity and thermodynamics.

[1]: https://en.wikipedia.org/wiki/One-electron_universe [2]: https://en.wikipedia.org/wiki/Boltzmann_brain

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by colordrops on Wednesday June 27, 2018 @04:08PM (#17411365)
It may or may not be a dreamy internet theory, but "Universe is NOT a simulation" is just as strong and difficult to prove of a statement, perhaps even harder as it's a negative.
Re:The Universe Is Not a Simulation, but We Can Now Simulate It by shawnz on Wednesday June 27, 2018 @03:42PM (#17411165)
> are astronomers and physicists taking it seriously?

What does such a theory have to do with astronomers or physicists? Its a philosophical issue

Re:The Universe Is Not a Simulation, but We Can Now Simulate It by comboy on Wednesday June 27, 2018 @03:58PM (#17411302)
Since nobody posted it yet, here's the paper: https://www.simulation-argument.com/simulation.html