Between modern physics suggesting time and space may be illusions, leading technologists agreeing that we're almost certainly in a simulated reality, and many ancient traditions being certain that this is all an illusion, I may have to have to go ahead and take this seriously....
The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it.
Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed").
The speed of light seems like a hack to prevent an n squared problem of everything in the universe effecting everything at the same time.
In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wave function. A CCD detector of a camera or a simple wall is enough to force that the "wave" collapse into a "particle" and the detector or wall gets a small spot where the "particle" hits it.
A similar experiment is possible with spin, and you can use that to get a qbit. In a classical word, a qbit is simply a bit and you only have to chose between the 0 or 1 state and simulate it. In a quantum word, you must simulate both.
But it's worst with many qbits. Let's say you have a 10 qbits computer. In a classical word you pick a value for each of them and simulate each one, so the total computation is ~10. In a quantum word, you can combine any of the states of the 10 qbits and you must simulate the 1024 states.
So the idea that a quantum computers is better than the classical computer is opposed to the idea that quantum physics is some hack to reduce computational resources.
I think that the main problem is the quantum mechanics is weird, use a lot of linear algebra, but the calculations are somewhat straightforward and well defined. But the popularization explanations try to avoid the algebra and make some simplifications, so the explanation only keeps the weird part.
I've been watching a few video series by mathematicians on quantum computers and they're pretty interesting. I wish they could hook up with some animators to make it a little easier to understand.
There's a lot of complex maths and polar notation. There are a couple of good simulators out there that lets you play with qubits and their probabilistic coefficients.
I'll be honest that I was never all that great at the higher maths and a lot of this taxes my brain or goes way above my head. But all these quantum computers are deterministic. The simulators can fully simulate them.
It's just that simulating several qubits requires gigs and gigs of ram. A real quantum computer can't do anything you can't do with a traditional computer, it can just do it in a more computational faster time and fewer resources.
You can run small quantum programs yourself on the IBM cloud quantum platform. They allow people to queue up programs to run, similar to old punch card systems:
> In a classical word, a qbit is simply a bit and you only have to chose between the 0 or 1 state and simulate it. In a quantum word, you must simulate both.
Not just "both", you have to consider all quantum states.
It is more like adding an imaginary component to a real probability making it a complex probability. It is possible to calculate with the complex probabilities and only collapse to the field of R in the end.
> In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wave function. A CCD detector of a camera or a simple wall is enough to force that the "wave" collapse into a "particle" and the detector or wall gets a small spot where the "particle" hits it.
While the alternative seems a little too far out to be true, I have to ask, how do you know?
> So the idea that a quantum computers is better than the classical computer is opposed to the idea that quantum physics is some hack to reduce computational resources.
Keep in mind, not all operations in a computer take the same amount of time. If those qubits are entangled, you are going to get the state of all of them from a single "operation". Finally, we assume deterministic and stochastic computation take the same time, but that's only true for us because we perform stochastic computations deterministically - I'm pretty sure we could squeeze a lot more performance out of our silicon if we relaxed our accuracy constraints.
Additionally, if the universe is a computing system, the probabilistic nature of quantum mechanics may be a way to work around paradoxes, i.e. Godel's incompleteness theorem.
Absolutely not. The uncertainty in Heisenberg's uncertainty principle stems from the fact that you can not have a signal simultaneously well localized in both time and frequency. If you want a signal that is very well localized in time, then you need a short signal, a single spike. But the frequency of a single spike is not well defined, if you want a signal with a well defined frequency, you need something like a sine wave. And to make the frequency of a sine wave well defined, you need a long piece of it which of course means that the signal is no longer well localized in time. That is the heart of Heisenberg's uncertainty principle, you can not have signals that are simultaneously well localized in time and frequency.
Gödel's incompleteness theorems have in some sense much deeper reasons, they are based on the logical consistency of the entire construction. Maybe you can look at it in a similar way, a theory is an object like a signal above and the properties of being consistent and complete can not be realized at the same time. But I have a hard time imagining that this could really be similar to signals where you can trade localization in time for localization in frequency and vice versa, but how would you trade a bit of consistency for a bit of completeness?
EDIT: To be a bit more concrete, in classical mechanics you have to specify position and momentum (velocity) of a particle to specify its state, those are two independent properties that can have specific and independent values. That is not true in quantum mechanics, there position or momentum alone fully specify the state of the system. The wave function (in position space) tells you where the particle is with what probability, the frequencies of the wave function tell you what the momenta are with what probability.
And from here it is the same as above, if you force a particle into a very well localized position, i.e. make the wave function a narrow spike at some place, then the frequencies and therefore the momenta are no longer well defined. If, on the other hand, you make the wave function of the particle like a sine wave, then you get a well defined frequency and therefore momentum but the wave function becomes spread out across space and the position is therefore no longer well localized.
>In 1927 Heisenberg discovered that the ``more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa''. Four years later G\"odel showed that a finitely specified, consistent formal system which is large enough to include arithmetic is incomplete. As both results express some kind of impossibility it is natural to ask whether there is any relation between them, and, indeed, this question has been repeatedly asked for a long time. The main interest seems to have been in possible implications of incompleteness to physics. In this note we will take interest in the {\it converse} implication and will offer a positive answer to the question: Does uncertainty imply incompleteness? We will show that algorithmic randomness is equivalent to a ``formal uncertainty principle'' which implies Chaitin's information-theoretic incompleteness. We also show that the derived uncertainty relation, for many computers, is physical. In fact, the formal uncertainty principle applies to {\it all} systems governed by the wave equation, not just quantum waves. This fact supports the conjecture that uncertainty implies randomness not only in mathematics, but also in physics.
That sounds ridiculous. The double slit experiment is a small system. The detector apparatus is much larger. The world outside of that, even more so. If your view is how the universe works, the number of superpositions of states that must exist between the "magical human observer" and the experimental result must be huge. Every particle in contact with every other particle. It seems ridiculous that the entire universe must be in superposition to give humans this special property.
The "observer" here is simply an outside system.
(FWIW, we only covered the basics of quantum mechanics in my chemistry undergrad. Perhaps a physicist can explain better.)
> In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wave function. A CCD detector of a camera or a simple wall is enough to force that the "wave" collapse into a "particle" and the detector or wall gets a small spot where the "particle" hits it.
This is a common misconception (among programmers). There's zero experimental evidence for the effect you mention, and zero theoretical derivation. Circumstances under which wave function collapses is the greatest mystery of QM.
> Circumstances under which wave function collapses is the greatest mystery of QM.
I agree with that.
Anyway, if you have an optical system, you can assume that coherence is present while the light hits mirrors, lens and similar optical equipment. (If the difference in the optical paths are smaller than the coherence length of your laser or light source.) But as soon as the light hits a white screen or a brick wall, all the further calculations must use only the intensity of the light at each spot in the screen, forgetting about the phase angle. And all the spots are not coherent.
It's not clear what cause the wave function collapse, but if you are using photons in the visible spectrum probably a mirror will not collapse it, and a brick wall will collapse it. [Or your preferred rewrite with the multiple word interpretation, or the abstract Hilbert space calculations.) I'm guessing decoherence is the correct explanation, there is a nice comment in a reply.
For other particles, the abstract calculation is equivalent, but it's necessary to choose another system to do the experiments.
If you follow the equations of the wave packet of the particle arriving to the wall (or CCD) detector, you then need to solve the equation of the interaction of the particle + all the particles in the wall or the CCD. The challenge of the collapse is that simulating anything beyond a few dozen quantum particles is too demanding. Mathematical models that simulate millions of particles need to make assumptions (typically they are too hot, too cold, too strongly bound, so you can ignore most effects - think 1D Ising model, Bose-Einstein Condensates, Photon gases, etc). But the full description of a particle + all particles in a detector still escapes us.
Therefore the transition between: superposition of paths -> particle lands at specific points has never been truly explored. The best description currently involves decoherence. Many theorems have been proven (and experiments done) in that area. The gist is that as you add particles to a system (2, 3, 4, 5, 10, ...) the superposition effects slowly cancel each other out. Another angle is the monogamy of entanglement (the more particles are entangled, the weaker the entanglement between any 2 particles). The idea of decoherence is that as things get larger, the weird effects of quantum physics become more "dilute". However, going from double slit to macroscopic reading still has many assumptions along the way.
Take the above explanation with a grain of salt (as I have tried to make it accessible).
The appearance that quantum effects might be attributed to 'hacks' probably has more to do with the hackish nature of the Copenhagen interpretation. For instance, there is no stated physical explanation for the collapse of a wavefunction--it is only an extremely convenient way of explaining many experiments. A crude analogy--you can describe the flipping of coins with simple probability, but this is a non-physical yet very convenient explanation.
Nothing changes at the time of "wave function collapse". When you measure one particle of an entangled pair, nothing actually happens to the other one. But you don't need to listen to me, check this out:
The wave function collapse and "spooky action at distance" for entangled particles are somewhat different concepts. The collapse idea arises as a part of Copenhagen interpretation, which states that particle always exists in a superposition state (aka wave function of probabilities). So when audience asks, "well why is it that my measurement device showing particle exists/doesn't exist in one place"? The interpretation then says, "That, my dear fried, is because the wave function collapsed to a single state just when you did the measurement". People have been trying to explain and figure out what/why/when this collapse occurs to make sense of Copenhagen interpretation.
That's true, but such proposed extensions or alternate interpretations are then filling in the gaps that would lead people down the path of the simulated universe in the first place.
Bohm's interpretation is just many worlds with a "world particle" tacked on. That particle doesn't affect anything and it's only purpose is to get rid of those pesky other worlds.
Not only is it superfluous structure it makes the theory non-local, which is hard to reconcile with relativity.
If you have no a priori reason to reject a multiverse Bohm's theory is quite uninteresting.
It's the most obvious counter-interpretation. I think it's become remarkably successful, but also suffers in its embrace of causality. While the Copenhagen interpretation can skirt the issue completely, Bohm's must wrangle with the implications of both relativity and non-locality and no one has been completely successful as such. Also, if it were the leading view, I don't think discussions of a simulated universe would be as popular.
> While the Copenhagen interpretation can skirt the issue completely, Bohm's must wrangle with the implications of both relativity and non-locality and no one has been completely successful as such.
Some might consider that a feature. John Bell of Bell's theorem thought QM's non-locality was the most important unresolved issue, so placing it front and center where it couldn't be ignored was a great idea. Interpretations like Copenhagen simply let you paper over the problems which will inevitably just arise elsewhere.
Finally, I think there's been some promising work in deriving covariant Bohmian mechanics. For instance, a preferred foliation of spacetime can be derived from the wave function itself [1], which means a preferred reference frame is actually a part of every interpretation of QM. This is the kind of result that probably would have never been found without research into Bohmian mechanics.
> Also, if it were the leading view, I don't think discussions of a simulated universe would be as popular.
I don't see why. Simulated reality is a purely logical argument [2].
You're right that simulation arguments generally don't rely on QM interpretations. I mention it as potentially detracting from simulation because a common argument includes the need for computational shortcuts. QM as it is popularized now simply fits the shortcut narrative better than it would under the Bohmian approach.
Yes. Many worlds is the single obvious solution. It seems some people don't understand many worlds though. Or maybe there is some other definition I am not aware. I want to describe my understanding here for people's benefit.
The idea is that when you make an observation nothing special happens at all. For one, there is no wave function collapse. This is more an idea about how the observer experiences making a measurement. The salient feature is that the observer is not external to the system. He is a part of the system. His belief that the result was heads or tails is coincident in the wave function with the coin being heads or tails. In other words, the user becomes entangled with the system.
A toy wave function would look like this (I am leaving off normalization since I can't write a square root of 2):
Coin flip result, no observer:
|heads> + |tails>
Coin flip with observer, "Tom":
|heads>|Tom: it was heads> + |tails>|Tom: it was tails>
There is no collapse here. However, to Tom it appears as if the world did collapse. For the "version" of him that thinks the coin flip came up heads, his entire world is consistent with the measurement coming up heads.
I assumed most people who really understand quantum mechanics believe this (but I may be wrong). And that among them, there is no effort to say "There is no collapse" because indeed the effective result of the measurement is a collapse. I also use the language "wave function collapse" to describe what happens. This not because it is an objective reality of the universe but because it is the way we observe the universe.
That was my understanding too. It's disappointing that it keeps getting explained along the lines of "every time there's a decision point at the quantum level, the universe splits in two", when it doesn't say anything of the sort (at least, not if I've understood it correctly).
This is the same confident, facile declaration by may technologists who blather on about how we are on the cusp (a decade or two away) of being able to "download" the state of a person's brain and so let them live forever, in a virtual simulation.
Such people are entirely ignorant of biology. The analogy to programming, the thing they do know something about, is and irresistible analogy because they don't know enough to see the massive flaws in the analogy.
To be more concrete, by using the computerese term of art "hack" you are begging the question.
His post gave concrete examples of how things look a little like hacks, while yours can literally be summarized as "technologists are ignorant of biology," which is a non-sequitur.
I think it's hubris to suggest that just because something is surprising to us that we explain it based on our experience with our own limited technology.
>The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it.
Err, while this might be used to support the hypothesis, the popularized and most discussed version of the simulation argument doesn't even really mention this [0].
To me, it seems like evolution. Because when you get down "to the metal" of the universe, it's really just a bunch of dirty hacks that are thrown together and give off the illusion of uniformity and grace. The way things work at a macroscopic level seem so grand and ultimate, but on the microscopic level of all that it's utter chaos. Random acts of chemical bonding happened to create the life forms we interact with every day, including each other.
The universe is a giant hack job, and I think it evolved that way. I'm a big believer in the "multiple nested universes" theory that our universe began as an offshoot of another, parent universe, and that some of the larger/heavier black holes in our universe could be gateways to other child universes.
I'm curious, how can you be a "big believer" in something that is entirely made up with absolutely no evidence of any sort to back it up?
And how do you mean, dirty hacks. Our fundamental physics nowadays is quite elegant, I'd say, and still we have many questions still to be answered and much deeper to delve till we hit the "bare metal". We've only been in the universe-figuring-out business for real for about 200 years after all!
> I'm a big believer in the "multiple nested universes" theory that our universe began as an offshoot of another, parent universe, and that some of the larger/heavier black holes in our universe could be gateways to other child universes.
but then there's the question of what came before the universe(s) ours originated from and what came before that and so on, since, following our current understanding, everything has an origin
even if we were to argue our universe is a simulation, who/what's running the simulation and where did that originate from? how did it come about?
Don't they only seem like hacks through our understanding, though? Once it's starts looking like a hack isn't it just as likely we're missing something that isn't necessarily a simulation issue?
The simulation argument comes from the fact that our brains are a simulation of our environment. And since they are a simulation we seem to feel as if this world is not real. The world is out there, but our world is in here. Some other people below get down to some of this stuff. We want things to be like this. But they are out there not in here.
We do not observe states, we observe (measure) "observables"; both exist independently from any observers; while state evolves deterministically, an observable, when measured, takes a value, subject to a probability distribution on a set of values, which depends on both the state and the observable in question. (That's basically QM in a nutshell.)
I haven't heard the 'dirty hack' argument before. Perhaps we only see those things as 'dirty hacks' because of the incompleteness and inelegance of our own theories.
Try this physics paper[1] explaining how pretty much every model we have of physics is broken in fundamental ways. Things you take for granted because of what you've read in popular media (eg., heat death of the universe) are simply speculation based on stretching an incomplete mathematical model to its limits. The simulated reality nonsense is the same bad logic in a different guise.
Oh I've read it. It's a fun game to read through it and write down all the unfounded assumptions the author makes. It also doesn't help that his ideas about the complexity of the human brain are sorely outdated.
If you cannot convincingly argue the opposing side, then you have not thought hard enough about it. If you have no room for doubt, then there is no point discussing it. You have reduced science to zealotry. Don't waste my time.
You have already made it clear that you think his argument is undeniable. But since you insist on trolling, let me start with the obvious one.
In order to simulate a human brain, you need to simulate physics. Not a mathematical model of physics, but the actual true process that governs nature. In order to do that, you need to (1) understand the true laws of physics and (2) the process needs to be simulatable in polynomial time (at the very least). Where in the essay does he give you a convincing argument that these are true? Or is it just the lack of impossibility enough to convince you that they are possible?
The other poster is correct to say that simulating physics isn't actually needed, because Bostrom's argument depends only on ancestor simulations, not ancestor universe simulations. So simulating people doesn't require a) simulating physics, b) simulating the minutiae of brains.
Since these are post-humans, they understand the subtle interconnected algorithms implemented by human brains, and so can in principle bypass the need for low-level simulation. But even if that were not so:
> In order to simulate a human brain, you need to simulate physics. Not a mathematical model of physics, but the actual true process that governs nature.
You seem to be drawing some implicit distinction you find meaningful between "real" and "simulated", but this distinction isn't explained, and doesn't seem meaningful in any case.
> In order to do that, you need to (1) understand the true laws of physics and
The laws of physics needed for such simulations are sufficiently understood by post-humans, ie. for all physical observations simulated ancestors might make, posthumans understand physics far beyond that. So even without a perfect understanding of physics, they merely need to replicate the physics understood by their simulated ancestors.
> (2) the process needs to be simulatable in polynomial time (at the very least).
I don't see why. We already run non-polynomial simulations all the time (such as to solve fluid dynamics for aerodynamics, or climate models). As long as the results are expected to be useful, we will run them. This is actually a core premise driving Bostrom's argument: that ancestor simulations will be useful to future social sciences and such.
But all of this is neither here nor there, because Bostrom's argument is exhaustive. If there are legit reasons why post-humans cannot run such simulations, and there very well might be, he already covers this possibility as "we will go extinct before reaching the posthuman stage".
Like I said, Bostrom's argument is solid and there is no wiggle room. You get to choose one of the possibilities, for properly articulated reasons, and no more.
Bostrom does not define posthuman (so saying "no wiggle room" is ridiculous), so these conclusions about what posthumans understand and do not understand are unjustified and moot. But let me continue:
Bostrom assumes all simulated minds will be "of a similar sort." Another assumption that "minds" are well understood.
Bostrom assumes we will never have the means to glean any information related to whether or not we are in a simulation. Indeed, compared to the unprecedented assumptions needed to admit posthumanity (computers the size of planets, for one!), the assumption that we can determine whether we are in a simulation seems paltry by comparison.
Bostrom's indifference argument is unfounded. In particular, say I only give his proof a 1/N chance of being correct for a very large N. Then by his indifference principle I _still_ must assign an overwhelming probability that I am in a simulation. This doesn't help in that I cannot be 100% certain his argument is wrong since he does not define things rigorously enough for a proof, nor can he possibly do so because of our lack of understanding about human minds or the future of computation. So to be a "rational" being (I hate this term, because it's also undefined), I can't disagree with his argument and conclude the opposite of what he concludes.
You're making the unfounded assumption that it is necessary to simulate "the actual true process that governs nature"; Bostrom's argument does not require this, it only requires a simulation of people with our kind of experiences.
I don't think there is any requirement for a simulated universe to have any fully consistent laws of physics, let alone the 'true' laws (whatever they are - the laws imputed to hold in the universe in which the simulation is actually run?)
The whole idea that Universe is a simulation vs real is absurd to me. What if the Universe is a simulation running in a computer no one actually built but just fluctuated into existence. Does that make it more real or still a simulation?
See, I'm with you in the primary portion of this statement- if we're in a simulation, it doesn't make us any less 'real' - it doesn't matter whether I'm made of atoms or the stray thoughts of a passing horsefly. It is nevertheless important and interesting to know what the underlying medium in which I exist is, especially because there's no especially compelling reason why many kinds of simulated being could not create effects outside of their simulating media, like a bit of malware breaking out of a sandboxes virtual machine.
Knowing what kind of simulation we're taking part in, assuming such knowledge is possible and processable in the simulated world, that's incredibly important and interesting knowledge! :)
> like a bit of malware breaking out of a sandboxes virtual machine
Since you're trying to demonstrate the impossibility of the situation, I think the analogy you're looking for is ransomware breaking out of your computer and kidnapping you.
The data/code/simulation can't suddenly escape the sandbox and materialize into whatever the "reality" is made of. For that reason, it is trivial if we are in a simulation.
>The data/code/simulation can't suddenly escape the sandbox and materialize into whatever the "reality" is made of. For that reason, it is trivial if we are in a simulation.
But that requires there to be 3D printers in place; designed, manufactured and connected to the universe simulator, by whomever it is that created this infrastructure, with the intention of allowing "real" objects to be created from within the simulator and provided (in a way) a public API for it.
There is also the fact that we can't use 3D printers to create "perfect" or generic objects.
Oh now, what nonsense. We're not talking about spontaneously manifesting outside of the "sandbox," we're talking about simulated objects/intelligences comprehending the medium in which they are simulated and then learning to create effects in that medium as if they were working from the outside in.
For example, if you were simulated as a series of electrical signals in a computer, and if you were simulated as having some decision-making capacity, you could decide to take certain actions inside he simulation that might, for example, contextually outside the simulation, change one electrical signal from 'on' to 'off'. Like, "this is the 0 1 switch that represents the aliveness/deadness of SpriteActor32605." If you knew you were in a simulation of this type and you learned how to locate memory addresses, you might be able to execute a rowhammer attack, for example, and gain some sort of user access and more straightforward method to interact with the signals out of which you were made.
I'm not indicating that it would be easy or even that it would be necessarily useful, but particularly if there isn't someone 'monitoring' the simulation (as in, the simulation is the result of randomness and there's nobody trying to eliminate unexpected behavior from the simulated beings), there's every reason to imagine that we could begin to understand and learn to manipulate the medium out of which we were made.
If, you know, we are actually in a simulation and dependent on outside information for continued existence. Which is not settled at all, merely proposed as an explanation for some of the peculiarities we note here.
apparently computers spring up from nothing into miraculous existence quite often
Abiogenesis, the existence of physics, every "discovery" that results in new-found understanding of what is, the universe itself.. life is a boltzmann brain, physics is a boltzmann brain, discoveries are boltzmann brains, the universe itself, a boltzmann brain?
That's not the kind of simulation being discussed. "Simulation" means an intentionally constructed simulation of the universe. Random fluctuations don't count:
There is no serious evidence for the simulation theory. It is more of a religious belief than a scientific theory since it poses more problems than it answers (who is running the simulation? How did they come to exist? What is their reality like? Etc.)
I don't think it's religious. It's more like a conjecture in mathematics, an idea meant to inspire questions. The fact that it poses more problems than it answers is the whole point!
We know that systems can be nested. Do we know that the systems we perceive and can test directly compose the most fundamental layer? How can we tell? If we want to have any faith in science and testing our direct experiences, we need to keep those questions in mind.
"There is no serious evidence for the simulation theory."
Well, there are weird effects that would make sense in a simulated world (like superposition until observed). But the argument is a statistical one.
Can a world be simulated in a computer?
If yes, how many worlds and individuals are simulated at the same time? (And it may make sense for example market research, science etc. Of cause the simulation will run much faster then the real world).
Then there is a problem. If the world CAN be simulated and MUCH MORE simulated individuals exists than real persons it is more likely for you to live in a simulation than in the real world. A point worth thinking about.
It's not a theory in the scientific sense as it is not substantiated, that is not the point. It is a very limited hypothesis.
So in the event that someone holds a firm an unwavering belief that we're in a simulation unrelated to availability of facts, then their belief would be akin to a religious belief, sure, but the intent of the simulation argument is not to claim that there is evidence we live in a simulation.
Specifically, it does not argue that we live in a simulation at all.
It presents the hypothesis that at least one of the three given propositions must be true (paraphrased):
1. Either very few human-level civilizations reach a stage where they can run ancestor simulations, OR
2. Very few such civilizations have any interest in running such simulations, OR
3. Most people live in a simulation.
Basically it boils down to an argument that if many civilizations reach a stage where they can and do run such simulations, then our odds of living in simulation by pure chance will be high.
But the argument says nothing about whether or not we live in a simulation in isolation, because the argument does not quantify the odds of 1 or 2, and even if it happens that the chances of living in a simulation are astronomically high chance, that is still not evidence that we are, it would just be an indication that we probably are.
But let's say it turns out we have something akin to a "soul" that can't be simulated. In that case the number of civilizations in #1 is 0, and we're not in a sinulation under any circumstances. Or the odds of hitting a Great Filter and die out before we reach the technological level necessary might simply be insanely high, in which case the number in #1 might very well be very close to 0.
It may also be that any civilization that reach such a stage first will hit a singularity or other event that changes its priorities such that nobody are interested in such a simulation, or can justify the effort or expense. In which case the number of civilizations interested in running such simulations even if possible may be close to 0 (these options may also affect #1 - it may be we opt to change our future in ways that sends us off in a different technological direction).
The point of the argument is exactly the questions it raises, first and foremost by making people think about the possibility, and secondly to make people think about what may prevent us from being able to (which is tangentially related to the Fermi paradox), and what might make us want to or not want to, and lastly the questions it raises about whether there are ways for us to quantify or investigate each of the propositions. E.g. if #3 holds, are there any ways we can determine if we are in a simulation or not?
It is a philosophical argument, put forth to present the possibility that we live in a simulation that similar to e.g. the Drake equation seeks to define a set of parameters to focus a discussion around. It is not the intent that we should just assert the 3rd proposition is true, as even if it is true, it does not resolve all the questions around the 1st and 2nd, and it would just raise new question (the hypothesis can apply recursively - if it is possible to run such a simulation, then if it is posible to also run such a simulation within a simulation, then how that does affect the propabilities? it might seem as it creates a rather large subset of possible solutions that would make the probability of being in an infinitely nested simulation approach infinity; is there something that would prevent that?)
So it's not a bad scientific theory - it's a good philosophical hypothesis. It might in the future give rise to scientific theories. E.g. attempts to define falsifiable bounds to the probabilities, or falsifiable predictions about properties the world must have if we are in a simulation or not in one. But for the moment, it is a philosophical argument, and attacking it for not being a scientific theory is aiming in the wrong direction.
Yeah, it seems to be a rehash of the old "maybe this is all a dream" idea. Which I suppose can be a fun thought experiment in highschool, but it's a little unsettling to see people to take it so seriously.
What is ironic is the amount of blind faith required to accept some of these things that are so completely against everything we experience. It's very nearly a religion.
I'd argue it is a religion. The word religion means to "bind back" or "yoke" [edited], i.e. to seek an understanding of the universe and our place in it.
That's what physicists and cosmologists do. These disciplines also fulfill the needs of scientists for meaning and community and ritual, not unlike Christianity or Islam or whatever.
Just because you might happen to believe something doesn't make it not a religion.
> The word religion means to "bind back" or "yolk",
No, it doesn't. Less importantly, you mean "yoke" and not "yolk", and more importantly you are confusing the definition of a the Latin word religare from which it is believed the Latin word religio may have been derived (from which, in turn, the Middle English "religion" meaning "life under monastic vows" may have been derived) with the definition of the Modern English word "religion".
The Modern English word religion doesn't mean the same thing as Latin religare, or even Latin religio, or even the original Middle English sense of religion.
> The Modern English word religion doesn't mean the same thing as Latin religare, or even Latin religio, or even the original Middle English sense of religion.
If you look at these lists of 'modern' definitions of religion, the plurality (if not the majority) of the ones from academia seem roughly aligned with the (disputed) etymology.
E.g. the William James quote: "[Religion is] the feelings, acts, and experiences of individual men in their solitude, so far as they apprehend themselves to stand in relation to whatever they may consider the divine."
That's basically another way of saying what I said, and I don't see any reason not to include scientists under that umbrella. I mean even the phrase from the paper "a quantum state eternally evolving in an infinite-dimensional Hilbert space" sounds an awful lot like a conception of "the divine".
The etymology wasn't disputed. What was disputed is the way you are playing with etymology in order to get it to fit your desired narrative.
The word religion means to "bind back" or "yoke" [edited], i.e. to seek an understanding of the universe and our place in it.
Here you are retconing. The religio or bond/obligation refers to a monastic vow. It has nothing to do with seeking an understanding of the universe or our place in it. Therefore, the etymology of the word religion is completely irrelevant to the conversation.
> Here you are retconing. The religio or bond/obligation refers to a monastic vow.
I didn't realize the etymology was in dispute, so my bad. But regardless of whether religare or relegare is the etymological origin of religio, wouldn't either predate the concept of a monastic bond by centuries?
> E.g. the William James quote: "[Religion is] the feelings, acts, and experiences of individual men in their solitude, so far as they apprehend themselves to stand in relation to whatever they may consider the divine."
I would say his quote refers to spirituality rather than religion.
In this case, as I've documented, the way many modern religious studies people use the word is closely aligned with the etymology I gave. Whether that etymology is historically accurate has been disputed, but the fact that people use the word to mean basically the same thing as the purported etymology is not.
Anyone with any knowledge of linguistics? Even when the etymologies are correct (and they rarely are) they're entirely orthogonal to what words actually mean in practice today because language is only defined by its use (and is highly contextual).
Well if you look at the question of why religion is such a prominent trait of the human species, we seem to have an innate bias in favor of the idea that the universe was created to allow for our existence. And it requires a certain amount of mental effort to resist that bias.
There probably is some utility in the belief of an Inscrutable Creator. We are curious, rational beings and we like to understand causal chains. There is intrinsic value in this understanding, and also extrinsic value, as this sort of understanding is the basis for human innovation in society. God is a pleasant enough non-terminating terminus to all causal chains, and His Inscrutability allows us to not worry too much about difficult questions. Of course, the entire Universe is a single physical process moving through spacetime, an unchanging sculpture embedded in 4 dimensions.
Each of us are carving an eternal (if minuscule) shape during our lives. All we ever do, all we ever can do, is move atoms and electrons around (intentional motion of our body against the resisting world) yet we arise from moving atoms (unintentional motion of our body, e.g. at the cellular and atomic level).
BTW our self awareness has only one possible good purpose: to do what no other life could do, could ever do, which is escape the bonds of gravity, and spread life beyond earth. If that is not possible, then our species, and all life we know of, will perish on this planet, in the long run if we're smart, in the short run if we're stupid. But space travel, even trips that are very close, are incredibly difficult and expensive. The solar system is likely out of human reach. Interstellar travel is likely out of reach even for hardy, intelligent robots.
So you have to come back, once again, to the value of the Inscrutable First Cause, which is: relax. You're gonna die someday, your sculpture will be closed off, but your carving it every day, including right now. Enjoy it! Make fun shapes!
If you believe that the leaves were rustled by a predator and you're wrong, you only waste some energy.
If you believe that the leaves were rustled by something inanimate and you're wrong, you get eaten by the predator.
There's an evolutionary advantage in expecting agency where there is none. Whether it's rustling leaves, the weather, celestial bodies or life itself.
To put it another way: if you see Jesus in your soup doesn't mean there's some divine truth in soup, it's just an artifact of your brain having evolved to recognise faces in a way that encourages false positives over false negatives.
Understand the fallibility of every aspect of yourself and a lot of supernaturalist arguments go out of the window.
Yup. Science has become somewhat like a religion for those who like to think logically. In the end, they can no more step out of their logical thinking than the zealots can step out of their faith based thinking. Both become dogmatic and a crutch...
This is wrong, very wrong. There is a big fundamental difference between science and religion: Scientist can invent new theories and change their mind when new evidence is discovered. Religious people stick to their beliefs no matter what.
Both are not inherently true. Just commonly the case. In my experience (with Eastern polytheistic religions) a lot of "religious" people are perfectly fine with science, while conversely many people who swear by science and logic seem viscerally contemptuous of anything not falling within the bounds of their worldview. No doubt religion by and large is detrimental (at least at this point in human evolution) and it has a huge amount of blood on its hands, but the spiritual/mystical core of most religions (admittedly almost completely ignored by the vast majority of its adherents since it is obtuse, ethereal and hard to pursue; not as easy as following orders and conforming) seems to be just as much a way of seeking after the ultimately nature of reality as is science. Just because it is not testable and repeateable like the scientific method doesn't mean it is false, since we still don't know the ultimate nature of reality. So it is good if both sides keep an open mind.
But, limiting debates to the observable, testable (falsifiable) and repeatable subset has helped us improve our understanding of the nature of physical reality.
It's a mistake to conclude science is a weak tool just because it produces less certain results in the social sciences. "Weak" is a relative measure, so science is only a weak tool if you can actually demonstrate the existence of a much better tool.
I wouldn't be so sure about that. Max Planck himself said:
"A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it." [1]
As a human institution, science won't ever be perfect. The fundamental notions of science (reduction, documentation, reproducibility, etc) are drastically different from the fundamental notions of religion.
I think the word "science" is too general for this discussion. You're talking about the scientific method, which is a rigorous process for building consistent models of our shared experience. Godel's theorem suggests that we might never be able to complete any of these models, but the method has still lead to amazing new ways of understanding the universe.
If we're talking about the hand-wavey mysticism of Michio Kaku or Deepak Chopra, or researchers who have decided to believe a particular unfalsifiable interpretation of QM, and will not be convinced otherwise, that stuff is closer to what I would call religion.
In that reduced way science becomes a study of theory within theory, derived logical connections. Once you assume a logical framework you're out of the hypothesis/test routine completely. I don't think that's a fair thing to do in comparison. Where things start out matters.
I might not understand your point, but are you basically saying that not all science requires math? To be fair, I've been thinking of physics in particular here.
Science isn't a religion but scientists can be zealots. The scientific principle is the antithesis of religion but scientists can be irrational like any other human.
The good thing about the modern era is that even when institutional biases may momentarily prevent a theory from gaining mainstream recognition at least it will be preserved as part of the body of scientific knowledge so future generations can rediscover it.
Scientism is just a catchy phrase for blind faith.
Most "scientism" I see in the wild is just people who were already indoctrinated into magical thinking treating "science" the same way they previously treated religious dogma.
It's irrelevant to science the same way astrology is irrelevant to astronomy. It's cargo cult "science"-iness.
Science becomes religion when scientists ignore empirical evidence in front of them because their textbooks or theories point out that that evidence cannot possibly exist, and then proceed to call those presenting that evidence as unscientific or irreligious.
I wonder, why so you think so? Why do you call an endeavor that seeks to provide an explanation and a model of reality consistent with empirical observatkons a religion, when it's precisely the opposite? Just because we are reaching strange and difficult conclusions that you may not like, that's no reason to dismiss it as zealotry.
Physicist here. I'd be very careful.. one of the major problems with modern physics, the field and people practicing it, is that they layer explanations with metaphors, and are too quick to embrace mysterious explanations. Much of this stems from the history of quantum mechanics, which was mathematically formalized a generation before intuitive interpretations were worked out by Everett, DeWitt, Bohm, etc. Still to this day physics students are taught "Don't try to make sense of it; humans aren't meant to understand. Just shut up and calculate." by teachers who followed the same advice and knew nothing else.
This is unfortunate as embracing mysteries keeps one from seeking out more fundamental interpretations that actually provide real insight into how things work.
Time and space being an illusion are similar. These notions come from the mathematics which can be formulated in such a way that time and/or space (depending on the theory) are not axiomatic assumptions but rather emergent artifacts of a more fundamental timeless (or rather, time-arrow-less) or spaceless (rather, non-local) formulations. But that's just math. Time and space are as real as anything else. If you doubt that, I have a 23-story window you can walk out of.
As real as anything else, sure. Of course, if the _whole show_ is a sham, it's interesting to ponder what the ways out might be. As a recent article suggested, perhaps don't look in the game, but look at the player. Which also turns out to be the advice of much of Eastern philosophy. I already have an interest there, and several signs seem to be hinting that it's worth digging deeper.
I wonder, which physics claims that space and time don't exist (how could it, "exists" is a metaphysical concept, physics only cares about mathematically describing the world and making predictions), and how do ancient traditions making claims work as an argument to anything (seeing as ancient traditions have made every claim form the world being in the back of a turtle to a middle-eastern bronze age carpenter being the son of the creator of the universe)?
> I wonder, which physics claims that space and time don't exist (how could it, "exists" is a metaphysical concept, physics only cares about mathematically describing the world and making predictions)
I think this is a common misconception. Scientific theories provide predictive power, but they also provide explanatory power. The latter has fallen out of favour due to quantum mechanics, despite plenty of good interpretations of QM that provide good explanations, but it has always featured prominently every other scientific theory.
And given explanatory power is important, every scientific theory also therefore defines an ontology (your metaphysical concepts). This too has always been part of science.
> "String theory, loop quantum gravity, causal-set theory: these are just a few of the approaches that theorists have taken. ... But when you take a step back from the dispute, you notice all agree on one essential lesson: the space-time that we inhabit is a construction. It is not fundamental to nature, but emerges from a deeper level of reality."
I think quantum physics and 'simulated reality' are one in the same. What's the difference between a reality which is only real when observed, and a reality which is only real when switched-on? What is the difference between a reality in which such reality is deterministic (ie. no free will (at the microlevel)), and a reality based on a pre-progammed algorithm?
>leading technologists agreeing that we're almost certainly in a simulated reality
Just to elaborate, this is really easy to show. Just take two pieces of paper, and scribble all over one of them for 10-15 minutes.
Then crumple them up and throw them to the ground.
The blank one will fall to the ground smoothly. But the one that has a lot of image information will tax the Universe's GPU, because it isn't able to compress it easily, so it'll fall slowly and in a jerky motion. it's really easy to see.
OH WAIT NO IT ISN'T. There's absolutely zero evidence of any kind whatsoever, not even a whisper of an indication, that we're living in a simulated reality, and the suggestion that leading technologists state we "almost certainly" in a simulated reality is absurd.
If you're talking about a VR-type simulation where observable reality is simulated, but our consciousness resides in a 'higher' level, then yes, something like what you describe could be an example of falsifiable evidence of simulated reality.
But in the case where we, ourselves reside entirely within a simulation (or whatever) then we're tied, lock-step, with the universe's time, and any jitters or pauses (even outright simulation termination) would be completely unobservable to observers within: the ants in SimAnt don't recognise when I pause the process in Task Manager.
your second paragraph is exactly my point: which is why it's an absurd claim that anyone is saying "we're almost certainly" living in a simulated environment. there's no way to know.
> The blank one will fall to the ground smoothly. But the one that has a lot of image information will tax the Universe's GPU, because it isn't able to compress it easily, so it'll fall slowly and in a jerky motion. it's really easy to see. OH WAIT NO IT ISN'T.
What an absurd "test". A trivial counterargument: your sense of time is also computed by the simulation, so no matter how much "real world time" might pass to compute some outcome, "logical world time" can march on at the same pace.
But this has nothing to do with the simulation argument anyway. I suggest you read it:
Very few are arguing that we're almost certainly in one. Philosphers like Nicholas Bostrom are arguing that either something will prevent most simulations from reaching a stage where we can or will simulate the past, or we most likely live in a simulation, but you'll note it's very possible that the answer is that we can't or won't too.
The problem is that we don't have the faintest clue what the probabilities of each of the propositions are.
Another big problem for these theories is the amount of memory needed to represent our simulation. We can easily estimate the lower bound on the number of bytes needed for this simulation, being the number of atoms in the Earth (assuming they can "fake" the rest of the universe by exploiting the low speed of light), which you would need to all know a number of properties off (at the very least position and momentum). That's at least 10^50, i.e. "frickin enormous". Where would they even put a computer of this size? How would they power it?
There's no reason to assume they'd need to retain all this data. You'd "only" need to be able to reconstitute representations of details that are actually observed. Other than that you only need to be able to reconstitute a believable representation.
Some have floated the idea that this could be behind some of the peculiarities of physics. E.g. quantum effects, wave/particle duality etc. Of course that is purse speculation.
> That's at least 10^50, i.e. "frickin enormous". Where would they even put a computer of this size? How would they power it?
It's "frickin enormous" by our standards. If we are in a simulation we don't know the properties of the outside universe. E.g. for what we know it fits in some kids PDA.
The problem with even thinking about this is that we don't have any kind of references to go by at all for what is or could be possible.
> Philosphers like Nicholas Bostrom are arguing that either something will prevent most simulations from reaching a stage where we can or will simulate the past, or we most likely live in a simulation
What do they mean by "simulate the past"? If we're talking actual true-to-history simulations, that is going to require an unprecedented amount of inital data on how the world was in the past. An there's no way for the system to collect all that data, seeing as it's in the past before the omnipotent simulator was created.
On the other hand, if they mean "simulations of some hypothetical past with loose connections to the actual past, Matrix-style", i.e. "they" have the freedom to generate the scenario we're in, why on earth would they choose this one with all the troubles and suffering in the world? Why not make one where everyone's a pony and we all eat rainbows and poop butterflies?
They are running into exactly the same debates that Christian philosophers have been struggling with for millenniae - why is there evil in the world created by God / our hyperintelligent great^{n}grandchildren? Which indicates to me they are much closer to religion than science.
It's a simplification of the argument for the sake of making the first two prepositions easier to swallow as possibilities.
Consider that if we can simulate consciousness, then we could conceivably simulate a near infinite set of variations of consciousness.
This would still affect our likelihood of being in a simulation, as we don't have any outside knowledge that lets us know which type of entities we "should" be. It doesn't need to be human-type civilizations simulating their ancestors, it could just as well be some aliens playing a hyper-advanced version of Spore and making disgusting aliens to creep out their friends.
But it is easier to get people to picture e.g. Sim2,000,000 simulating full brains based on actual humans, set in a world based on "our" earth as having relevance to our existence, and it makes it more relevant to speculate on proposition #1 and #2. E.g. is there anything in human type society that will prevent us from getting there or wanting to do it?
> On the other hand, if they mean "simulations of some hypothetical past with loose connections to the actual past, Matrix-style", i.e. "they" have the freedom to generate the scenario we're in, why on earth would they choose this one with all the troubles and suffering in the world? Why not make one where everyone's a pony and we all eat rainbows and poop butterflies?
I don't know about you, but most of my Civilization/FreeCiv/Civ:CTP games ends up with things like nuclear war or brutal conquest - it's a lot more interesting to play the games in extreme directions. It's a good question, and one reason to explore this problem space.
Even so, in some sense it's not quite the right question: The point is that with high values for propositions #1 and #2, we could just happen to be in one of a potentially nearly infinite number of simulated realities. Perhaps they're running vast quantities of them to figure out of different choices would have different outcomes, for example. Or perhaps we're some kids afternoon entertainment.
We don't have a way of telling.
Unless we know that the possible set of "realities" is low, however, it makes little sense to speculate in whether there is anything "special" about "just this" simulation, because we have no basis for determining whether or not there is anything special or if the number of simulations is just so great that "ours" is just one tiny variation in a near endless sequence.
> They are running into exactly the same debates that Christian philosophers have been struggling with for millenniae - why is there evil in the world created by God / our hyperintelligent great^{n}grandchildren? Which indicates to me they are much closer to religion than science.
I'll repeat myself: It's not meant to be science. It's a philosophical argument. Nicholas Bostrom is a philosopher. It's his job to be a philosopher, not to set out scientific theories. Scientific theories could arise from speculation around the choices in question, such as e.g. whether or not there could be possible ways of determining if we're in a simulation, that might yield hypotheses that could be tested and potentially falsified.
But until that time, what separates this argument from religion is that the argument is not making any claims for either possible outcome - it is setting out a set of possibilities and asking questions around what we can learn from it.
As I've said elsewhere, if someone picks one on belief and sticks to it in the face of contradictory evidence, that'd be akin to religion. But asking questions and seeking ways of refining those into testable hypotheses is not religion.
Drop two pieces of paper towards two high information constructs (massive bodies), and time will pass more slowly for the one approaching the more massive body. Oh, and for someone flying with the rotation of the earth, time passes more quickly than flying against it.
Science is by definition incomplete. It only provides a means for proposing theories to test observed phenomenon, test them, and use them to extrapolate and make future predictions, which can invalidate or strengthen the theory.
e.g. we don't even know if the physics we have is universal or local to our observable corner, the only evidence we have is we haven't seen any evidence to disprove it, but that's not proof.
String theory could be considered dogma. But it at least provides means to test its predictions, its just that we are very very far off from ever getting close to that capability.
If we live in an illusion, its entirely possible and in fact likely that it is beyond our ability to even detect that. In fact that would be one of the first requirements of such a 'program'. You can should 'computer, end program!' all you like but the holodeck will just ignore you :)
There really is no point to wondering about the reality of time if it doesn't lead to anything we can test/influence or use to advance our understanding and so far there is none.
You could just say the entire universe is but one of infinite multiverses which are being continuously spawned in the cosmic sea, but that doesn't change anything.
> There really is no point to wondering about the reality of time if it doesn't lead to anything we can test/influence or use to advance our understanding and so far there is none.
I think this is wrong. There are some (possibly many) such apparently pointless questions that eventually lead to actual experiments. I remember that Einstein's book's about relativity theory starts with such questions. Off the top of my head, questions such as "how could you prove that two events in different places have happened at the same time."
I'd also argue that the whole concept of science came from the Philosophers from ancient Greece trying to answer such unanswerable questions. But this may require a longer dissertation :).
Can you elaborate why the string theory could be considered dogma?
I guess it's somehow related to the way it ways discovered/proposed, but I don't know much about it.
Seems like a lot of the problem with "time" is semantic. Do things change? Yes, and if that's the definition then it certainly exists.
But people don't generally see time like that, they think of it as some medium, or 4th dimension, that can possibly be traveled through. This kind of time does not exist (as much as anything can't exist). There are only particles and their positions. Traveling back in time would require moving every particle in the universe back to the state you want to experience. But this is not "traditional" time travel, just god-like influence over particles. Traveling back in time, in how people fantasize about it, would require copies of the universe being made every plank-time, that you can visit. And even that is just another 3d space that happens to look like one you saw before.
Time is chemical and physical reactions. The minimum amount of time (sorry) a reaction can take to happen is possibly plank-time. Nothing can "happen" faster than plank time. So time is possibly granular. If reactions stopped happening, time would stop.
In relativity we can model time as a dimension, with great success. But even there it is always evident that the time dimension is very different from the spatial ones; for one, we cannot travel in it. I believe GP is only saying this is the problem, ignoring that the time dimension is very special.
That's the sci-fi terminology and view that complicates and confuses the issue. Can reactions happen faster or slower, yes. No need to say "travel", that word has distinct meaning and connotations that lead to incorrect possibilities.
You have unknowingly stumbled into the heart of Special Relativity :) "travel" is the same all dimensions. If you think you are moving from (x1,y1,z1) to (x2,y2,z2) you are actually moving from (x1,y1,z1,t1) to (x2,y2,z2,t2). If you think you are staying put at (x1,y1,z1), then you are continuously moving from (x1,y1,z1,t1) to (x1,y1,z1,t2) to (x1,y1,z1,t3) and so on. The more you move in space, the less you move in time.
Also, when you put General Relativity in the picture, any sort of movement within this 4D space is possible (because the geometry of this space is wrapped) go to past, future, anything.
Your comment perfectly crystalizes everything I'm trying to say. You explain the relationship of time to space very nicely and succinctly and correctly, however you decided to use the word "move", which comes with a lot of 3d baggage, which leads you to start thinking that "any sort of movement within this 4D space is possible". Nothing in relativity shows that freely moving back and forward in the time dimension is possible. The closest semblance is slowing your own time relative to other things you care about, so that, for example, you can have the body of a 30yr-old while earth is at 3000AD, but again that's not "traveling" around time, it's closer to putting food in the fridge so it spoils slower.
I don't know if physicists do it on purpose to get published, or whether they've drank too much of the kool-aid, but "dimension" is another one of those terribly overloaded terms. String theorists say that the universe may have 11 dimensions. So cool! I wonder what's in them!? Maybe my childhood puppy is there! But do you know what they mean? Only that one or more of their equations had an exponent of 11. That's it. There is no correlation or evidence of that translating to physical, or interesting, dimensions that we think of.
+ A discrete, infinite Hilbert space, with (wave) functions defined at each point. Why discrete?
+ An operator across this Hilbert space that describes the evoltion of the universe.
+ A non-recurring property of the overall system that depends on the infinity of the system.
- Question. If the system is really big, can we see if it is recurrent or not?
- Question. Deviations from equilibrium should be "minor". However, minor deviations on a very fundamental level (of quantumgravity) might perhaps result in genesis/destruction of complete universes. If there is some kind of process that goes to low entropy can it be self-inforcing till it big bangs?
- Question. If time is a parameter for the universe's walk in Hilbert space, why is it real?
Another interesting thought experiment: what if time (rather entropy) is the only thing that exists? While highly likely to be untrue, it's an interesting mode of thought: as matter dominated beings we naturally approach conclusions from the perspective of matter.
You could also ask, what if time is the primary thing that exists? That is, it has authority over everything else that exists. This would mean that the laws of physics, for example, could change over time.
According to the theory, "they" just set the initial parameters (big bang one would assume) and let things happen. Intelligence is just one of the many random evolutions of mater states in a vast simulation of the universe.
It will be accelerated if for example we as humans start a similar simulation of our own. And inside that simulation some other intelligent life evolves. So likewise we may be n levels deep ourselves and never know any better.
I would argue that the concept of time is what is used to explain the transition between two states, not the difference between them. Time is not required for either state to exist by itself, but because the speed of light is finite it must take a finite amount of time to change one configuration of matter (state) into another one.
The difficulty is in defining "change" and "transition" without using the concept of time. The circularity is difficult to avoid. This is the classic paper that started it all: https://en.wikipedia.org/wiki/The_Unreality_of_Time
Time is not necessary for change to occur, I would argue.
For example, how long does it take for a thought to disappear? I would argue it disappears in no time, or at least that it can do so. There isn't any transition period where only half a thought exists (what's the half of the thought "apple")?
If we're talking about physical reality/matter, however, it must take time, because of the limits of the speed of light.
Or that there really is only one unchanging state, and what you perceive to be the passage of time is really just a very particular configuration of your 'memory' through which you 'remember' a different state, and that hasn't really changed at all.
Theory of relativity would say that there are many 'nows', which one you're in depends on which frame of reference you're in :)
To a photon traveling at c, the birth, growth, and death of the universe happen simultaneously; so to a photon, there is no now. From its perspective, it dies just as quickly as it comes into existence.
> Is there not just one ever present now in which all thing change?
Sure there may be; but going by the hypothetical possibility I raised, there really isn't a now. The passage of time could be an illusion due to your memory being in a particular unchanging state that has existed 'forever'. Who's to say the 'now' that has just passed wasn't just you remembering it?
Exactly; it's the measurement of change. As long as things are changing, time exists. (The fact that this discussion is taking place proves it's existence!)
The issue with your definition can be shown when thinking about the absolute zero point (that is, 0°K): as per definition in this state, particles lack any kind of energy. Common tongue would say that it is "frozen". Now if this state lasts, let's say, indefinitely, time would be non-existent. As there is absolutely no change in the state of the particle.
PS: Although one could now argue that the act of observation changes its state.
As the universe approaches heat death, quantum mechanics dictates that particles jump between states randomly, such that passage of time cannot be measured meaningfully.
Not just two states but causality. Something causes something else to happen. Although Sean Carroll says causality is an illusion, everything is "pre-defined". This just happen to flow one direction at a macro scale.
>Time exists. It's the observed difference between two states.
For something to be said to exist, must it not be immediately observable in the present?
Since state is perpetually changing, isn't "the observed difference between two states" always an observation of the past and never the present?
Perhaps it is more precise to say that change exists rather than time because "the observed difference between two states" can never include the present state.
Exactly!!! To me this is the obvious consequence. Another thing is Fermat's principle, if time doesn't exist then what is light minimizing as it moves through space?
Aren't you showing necessity? If you transition from state A -> B , then X must hold. Where X is conservation of energy, charge, etc... It doesn't say anything about how long it takes to get from state A to state B. Or time existing per se, rather some relations that must hold between states. They don't actually have to hold, but you don't live in those invalid states. Similar to constructive light perhaps.
I remember the old boost mode on PCs where you could run your game 2x as fast by increasing the CPU clock speed (increasing game transitions relative to brain transitions), and yet the rules of the game still hold despite the game transitioning faster. Also making very hard to see/play (No turbo boost for the brain :)
Chemistry nobel Ilya Prigogine has defended the idea beautifully in his books embedding the hard science in a wider humanistic context, including biology, ecology, urbanism, societal, entomology and other examples. He kindled my interest in dynamics and makes a huge effort to be understandable.
Save me some Googling and time, is this a documentary with information or is it a bunch of people with doctorates in angel therapy like What the bleep do we know?
It is part of an excellent PBS documentary by Brian Greene - the Fabric of Cosmos. It discusses Newtonian View, Relativity revolution, etc. Though it doesn't go to the depth of quantum cosmology levels as in the parent post.
