None seems not at all relevant? So all seems relevant? — EugeneW

Thx. Double negative fixed.

It depends how you view the wavefunction. In the standard Copenhagen view it's a mathematical aid.

True. Copenhagen is/was an epistemological interpretation, and as such, the only way anybody is going to learn about the state of some system (like the existence of Napoleon and TutCommon, the latter being the more ordinary brother of Tutankhamun) is to take a measurement (like read a history book) which collapses your knowledge from <maybe either> to <yes Napoleon, no TutCommon>.
As such, an act (reading a book, getting a sunburn) is required to change your knowledge.
It's like the shell game: the ball is under one of three shells and you don't know which until you life the shells. But not knowing where the ball is is absolutely not the same thing as the ball being in superposition of those three places. That's a metaphysical state which means (for the purpose of this discussion) that a real possibility exists for it to be anywhere instead of in fact under the left shell, unbeknownst to you. Superposition (QM definition this time) means that those three states can be made to interfere with each other in some way, which would be a metaphysically different state.

I am admittedly, in my posts, talking about metaphysical wavefunction collapse (or lack thereof) which narrows the interpretation choices to the metaphysical ones (which includes a metaphysical version of Copenhagen in which humans once again play no role).

The other approach, which I use here, is that there is a layer of determination beneath the chance: hidden variables. These are real features.

You've been speaking of locality before, and now there's hidden variables, used only by interpretations which abandon locality.

For the most part, and for purposes of this topic, I don't care. My observation was that RQM is an elegant solution to the origin problem. I really don't care that the other interpretations don't solve the problem the same way, or don't solve it at all. There are no hidden variables in RQM, and humans do not play any preferred role.

I don't recall much mention of any philosophical aspects/consequences of his theories, that he discussed in his YouTube offerings but I was too busy trying to gain some understanding of his scientific musings. — universeness

Then the videos are likely to be of little use to me since it is precisely the philosophical implications that have a direct bearing on the OP question. I'm not going to disagree with the physics of those guys. I'm in the wrong league for that.
I have had direct communication with Tegmark and don't disagree with any of his physics, but there are some metaphysical points on which we disagree. The quantum suicide thing for instance makes some serious errors, and does not in fact constitute evidence of his favored interpretation.

My time is limited, and I've yet to get to the videos.

I have no idea what you mean by this? A rock can take a measurement? in what sense? I assume you don't mean this literally

I mean it very literally. It is the effect end of a cause-effect relationship. Any superposition of the measured system is lost relative to the rock. Some molecule of Napoleon's dying breath interacts with the rock, changing the state (the momentum perhaps) of at least one particle of the rock. The rock is now different than it would have been without that measurement, thus Napoleon exists relative to that rock (as if he didn't already, but it's this particular measurement we're using in the example). The world cannot be measured to be in the state of that rock's exact state, but with Napoleon never having been.

I don't know how EugeneW would have expressed that since he seems to assert the necessity of a two-way 'virtual' interaction, which implies that Napoleon cannot exist relative to me (I cannot have measured Napoleon) unless I also exist relative to him (Napoleon has measured me, which violates locality).

That you have no idea about this means you need to spend more time learning physics from reviewed textbooks and not pop videos and articles, which almost always focus on the more relatable humans, their actions, and the epistemological aspects of knowledge of a system instead of the actual metaphysical state of a system.

Well, a wave function will produce a waveform, will it not?

It is a description of a system (somewhere) from a point of view. It doesn't necessarily 'produce' anything, but the future state of the system in question, if closed, can be described by evolving the wavefunction over time using Schrodinger's equation. Not sure if you'd consider that the production of a waveform. So maybe it's an atom with a half-life, and the wavefunction will give the state of the unmeasured system at any time. Upon measurement, the wavefunction collapses into a simpler state (typically decayed or not) instead of the superposition of all possible states of <decayed maybe>.

and all waveforms moving in 3D space will produce a worldline as it traverses space from its origin.

No. Wavefunctions are not objects that move around. They're descriptions.

Like a drop of water in an ocean that will cause only a localised disturbance and then settle as it dissipates its energy. It does not affect the entire ocean. I don't know what you mean by the wavefunction of a distant system relative to 'here' is nevertheless 'here'.

EugeneW worded it that way, giving a wavefunction the location of the point-of-view in question, hence measurements here collapse the local wavefunction here that describes the non-local system elsewhere. This makes sense in a local interpretation (of which RQM is one). If I measure one particle of an entangled pair, it doesn't physically make any change to the other particle elsewhere. No local interpretation supports 'spooky action at a distance' the way that non-local interpretations do. No reverse causality, with actions now having effects billions of years ago. There are very much interpretations that suggest otherwise.

light waves from a distant star still have to traverse the distance between here and its origin, which is why we see what was, not what is. maybe I am being a bit dense here but I am not following your logic very well.

Agree with this. Say the star is a light year away (impossible of course). To word it differently, only the state of the distant star a year ago is in our past light cone, and thus the wavefunction of that star from the point of view of Earth is collapsed only to its year-old state, and its present state is not in any way fact, relative to us. Likewise, a star sufficiently distant (say 50 GLY) doesn't meaningfully exist at all relative to Earth. Unmeasured state is not meaningful to a local interpretation. That's a very hard pill to swallow, but I find it an even harder pill to abandon locality, that information can travel backwards in time or anywhere else outside its future light cone.

I think I understand your words but then how do particles 'interact.' Perhaps ↪EugeneW can explain to me what you mean more clearly. I often turn to him, regarding cosmology stuff that I dont fully grasp.

I cannot understand EugeneW, so I don't think an explanation of what I mean is going to come from him.

You stated that observers cant fully understand a system that they are a part of so it's that which I disagree with.

I don't think I disagreed with that either. I said a system cannot collapse its own wavefunction. Superposition would be nonexistent if it were otherwise.

Act' makes it sound like some action or intent is required, and 'act of observation' makes it sound like a human is required to be involved in the act.
— noAxioms

In standard QM this is actually the case. — EugeneW

Are you agreeing with me or disagreeing?

An event in physics is not actually an event. It's the time and position of a particle. If particles were devoid of charge all individualities of partìcles would be lost and the universe would spread out into a uniform mass in which nothing could be defined or have outlines. All would be one. When particles interact, by their charges coupling to the omnipresent field of virtual particles, their evolving wavefunctions (which are, loosely speaking, the temporal cross sections of quantum fields, collapse every time upon an interaction. The standard view doesn't speak of collapse but the objective collapse approach does.

So particles tract characteristics and identity because a relation with other particles. Their condensation in spacetime are relational.

None of this seems at all relevant to my comment quoted above.

I'm not trying to convey Rovelli's views. I've not read the work you name. But the view is at least loosely based on his concept, but driven to its logical conclusion.
— noAxioms

I think we have been mostly talking past each other. I thought you were narrating Rovelli's views — universeness

It says 'loosely based'. Rovelli certainly has the physics part down, but not having read his works, I don't know if he's explored the philosophical implications of his ontology, such as that of identity for example.

your first response to me stated:
The collapse of the wave function due to the act of observation?
— universeness
That's a poor representation of Rovelli's interpretation
— noAxioms

I restored some of the context. That reply of mine referred to your usage of "act of observation" which sounds like a pop wording at best, and not how a physicist might have put it.
'Act' makes it sound like some action or intent is required, and 'act of observation' makes it sound like a human is required to be involved in the act. There's never been evidence of this. A rock can take a measurement and collapse the wave function of some non-rock system just fine, all without actually observing or knowing anything. So it was the pop-representation that I meant to label a poor representation of the science, and not of Rovelli's view in particular.

I think Rovelli's posit that the measurement problem and waveform collapse is a localised phenomena which only occurs between interacting systems X and Y and is not a 'Universal/objective effect,' is very interesting. The waveform does not collapse from the reference point of the whole Universe.

With that we seem to both agree. It implies that a wavefunction has a location (which I would not have intuitively suggested), and that a wavefunction of a distant system relative to 'here' is nevertheless 'here'.

I would not have said that spatially systems can 'interact' since I consider a system to be essentially an event and not say a worldline like Rovelli implies. We obviously differ on this point, but I can drive the worldline view to contradiction, a philosophical problem which seems not to concern Rovelli, being a physicist mostly interested in empirical consistency.
Two events cannot 'interact' since that would require each to be in the other's past light cone.

I don't think Rovelli has ever suggested that the structure and fundamental workings of the Universe are unknowable

Did I suggest anything along those lines?

I have WATCHED his youtube videos, his lectures and his discussions with Sean Carroll etc.
I haven't READ any of his publishings.

Perhaps you can recommend some Rovelli vids, even though I don't usually get my science from videos. Then I can point out places where I might not agree with Rovelli.

Superposition is collapsed by a virtual photon. An interaction is involved. — EugeneW

That might be one way, especially for a realist interpretation.

You seem to envision poking the cat with a stick, but measurement of the moon does not seem to involve virtual photons, so collapse does not necessarily involve such a virtual interaction.

A state of superposition remains superimposed without interaction. A superposition of spin up and down won't collapse by emission of a photon carrying info to the observer. Measuring the spin means placing the superposition in an external field. — EugeneW

You have a reference for any of this? This seems to violate locality for one thing.

The universe (as a whole) doesn't need an origin story, lacking anything that measures the universe. That would require an external observer.
— noAxioms

I took this to mean that only an external observer of the Universe could make measurements/perform experiments on the Universe (as a whole) and by doing so, discover its structure and workings. — universeness

I didn't mean that with that comment, which was specific to the relational interpretation.
I don't see how 'experiments' could be performed by an external observer given definitions and models where such an observer is meaningful.

A model could in principle be simulated by something not part of the universe modeled, and experiments might consist of different initial conditions or something.

I took it that you were basing this view on your other view that internal measurers (human or electronic sensor) cannot gain the necessary data as they are part of the Universe.

I forget the context of when I said that. Data necessary for what again?

By definition, there can be no such observer. Any such observer would be part of the universe.
I grant that similar to a simple quantum system in a thought experiment, the structure of the entire universe can be considered from 'outside', but that's different than measuring. No wave function collapse results from objective analysis of a wavefunction of some closed system.
— noAxioms

Are you using the argument that no observer can exist 'outside' of our Universe?

By definition, given the relational (or any non-counterfactual) interpretation, nothing external (or even sufficiently distant) can exist since it cannot be measured. But given a different definition of 'exists', the rules might be different.

are you saying we can never know the origin story of the universe based on the points you make that an outside observer would be needed ...

There is no origin story. Only a realist interpretation requires an origin story to explain the reality of whatever is asserted to be real. Positing an 'outside observer' doesn't change that.

If an observer can be conceived as 'outside' of the Universe then how would they be part of it?
That makes no sense to me.

Totally agree. So if it interacts, it is not outside. If it's outside, it can't interact.

What evidence are you calling upon that demonstrates that objective analysis of a waveform is a closed system?

I'm not suggesting it necessarily is. The wavefunction of the universe is supposedly by definition closed, and thus an analysis of 'the universe' (defined as that wavefunction) would be an analysis of a closed system, but open systems can also be objectively analyzed.

hat are you defining as 'objective' and 'closed'?

Objective is an adjective which I am using in opposition to 'relative'. Objective existence is realism: The ontological property of existence even in the absence of observation. Relative existence is a relation: A exists to B, but A might not exist to C.

I am trying to follow a smooth line of logic in your narration of 'The structure and workings of the Universe,' as suggested by Carlo Rovelli.

I'm not trying to convey Rovelli's views. I've not read the work you name. But the view is at least loosely based on his concept, but driven to its logical conclusion.

I have tried to narrate the basics of his viewpoint as I conceive it, based on the youtube videos he offers. You may have a better understanding of his viewpoint than I do.

Or not... Not sure if I'd score better than you on a test of his works.

The bottle with poison breaks and kills the cat or not. If the superposition of, say, spin (thumb,) up and down interacts with a photon from outside, the photon can make it collapse to up (cat lives) or down (cat dies). Before the photon hits the superposition, the cat is just alive. — EugeneW

None of this is expressed as a relation, so the assertions of state are according to different interpretations. 'The superposition' is not an object which a photon can hit. If a measurement of the spin of some particle is taken, it usually involves information (photon?) traveling from the state being measured to the measurer, not the other way around.

It could well be that I was not attentive enough when watching Rovelli on YouTube. — universeness

YouTube almost always uses human observers in their examples, and yet in real experiments, the human is often not present during any of the measurements, all of which are taken and recorded by inanimate equipment, say a screen upon which an interference pattern appears.

So, I assume you are saying that according to Rovelli, it's not the observer that's causing the waveform collapse it's the local interaction between x and y.

According to quantum mechanics theory (rather than any metaphysical interpretation of that theory), there is no evidence that humans play a special role in physical waveform collapse. Humans do play a role in epistemological collapse: Even if somebody else watched, one particular lab guy isn't going to know where the photon was detected without at some point measuring the result, however indirectly. That doesn't mean that the photon didn't in fact get measured at a particular location.

An observer can measure, whether it's human or sensor, I think you are making an unimportant distinction here.

I'm balking at the connotations of using human verbs (like 'looking') when describing an interaction of any kind between two arbitrary systems. It is precisely that language usage that caused the naive readers back in the day to conclude that QM somehow provided evidence that humans were special. And, the 'oberver' need not be a sensor at all. It need not be anything designed with the purpose of specifically measuring the system. A photon can hit, instead of a photo-sensitive screen, just a black wall and be lost forever. The wavefunction is still collapsed relative to the system containing that wall.

Humans desire an origin story for themselves and therefore for the Universe. I think that desire is significant even though I agree with all of Carl Sagan's great demotions.

Totally agree. Humans want this. How to explain the reality of whatever it is that you must assert to be objectively real to satisfy your desire for warm fuzziness. But the explanations always require dancing around an inevitable contradiction, and it seemed far simpler to not assert the objective reality in the first place.

I understand your narration of Rovelli's view of Schrodinger's cat from the reference frame of the cat but you said earlier that only an observer from outside of the Universe can make measurements on the Universe that would reveal its true structure (is that what you are saying?).

By definition, there can be no such observer. Any such observer would be part of the universe.
I grant that similar to a simple quantum system in a thought experiment, the structure of the entire universe can be considered from 'outside', but that's different than measuring. No wave function collapse results from objective analysis of a wavefunction of some closed system.

Does this not suggest that an observer outside of the box containing Schrodinger's cat should be able to know if the cat is dead or alive or is it merely the fact that the observer outside the box cannot see through the box?

I have no idea what I wrote that might suggest the outside observer could acquire knowledge concerning the state of the unmeasured cat.

If so, then surely you are assuming that anything outside of the Universe would have an ability to interact with the Universe.

Again, that would make the observer part of the universe, and not outside it.

As I have said before, my expertise is computing not cosmology but cosmology is of great interest to me.

Cool. I'm a software engineer myself, hardly a cosmologist.

What I meant is, why can't the Schrödinger cat actually collapse without someone looking, observing. — EugeneW

First of all, I balk at the word 'looking', since it makes it appear that humans or life forms play a preferred role. I can think of only one interpretation that suggests that, and even it was abandoned by its author (Wigner) due to it being driven to solipsism.
Secondly, I am not offering a falsification of objective collapse interpretations, but the relational interpretation isn't one of them. Relative to what system would the cat collapse without said system measuring the cat?

↪noAxioms
Why shouldn't a system be able to measure itself? — EugeneW

That was explained in my post. It would be akin to the cat (or any system) collapsing its own wavefunction, preventing it from being in a state of superposition relative to some other system. Superposition state would then never be observed.

Secondly and a bit more formally, a system at a time is not local, and it takes time to measure something non-local, so no non-local thing can measure itself:
A system at a given time (Y) can measure its past state (X), but its past state cannot measure the later state, so while X exists in relation to Y, Y does not exist in relation to X. If X and Y were the same thing, that would be a violation of law of non-contradiction, so X and Y are not the same thing, and thus no self-measurement has been done by any system.

If an observer measures Schrödinger's cat, it is said that the whole of the observer and cat is still in a superposition and that a second observer collapses that superimposed state.

Yes. That seems to be a statement that X might be measured by Y, but Z may not have measured either, so the state of X and Y is not collapsed in relation to Z. So no objective state for anything. The state of any (X say) is a relation with some other system Y or Z, and not necessarily the same state, as your example illustrates. Hence it being meaningless to say something like 'X exists' without a relation, similar to saying that events 1 and 2 are simultaneous without specification of a reference frame.

So the last observer will always remain in a superposition.

Which means the whole universe stays in one. Weird. But it logically follows. So time for a change.[/quote]Unintuitive maybe, but you seem to be able to follow it. Most don't get that far, balking when it rubs the intuitions/biases the wrong way.

Point is, the universe is not in need of existence if there's no external observer relative to which it is need of being.

I take more of a relational view, like RQM (Rovelli).
X exists relative to Y iff Y measures X. But there is no meaning to X exists or Y exists since it isn't expressed as a relation.
— noAxioms
I'm not sure I fully understand your algebraic/relational argument here but are you talking about Rovelli's proposal regarding the measurement problem?
The collapse of the wave function due to the act of observation? — universeness

That's a poor representation of Rovelli's interpretation. It makes it sound like humans or things that 'observe' make any difference, which couldn't be further from what he says.
Any interaction between two causally separated systems results in a collapse of the wave function of the 'cause' system in relation to the 'effect' system.

The view, driven to its logical conclusion results in an ontology that doesn't suggest an 'existence' in need of being brought into existence, hence being an elegant solution to the problem posed in the OP. That was my point.

I think he suggests that this affect is only local, between the two systems X and Y involved.
The waveform only collapses from the standpoint of the observer not from the standpoint of the Universe.

Exactly, except I'd not have used the word 'observer'. Measurer maybe.

do you mean you cannot find out the origin story of the Universe by the act of experimental measurement?

The universe (as a whole) doesn't need an origin story, lacking anything that measures the universe. That would require an external observer. Internal interaction only results in self-consistent state.
Rovelli says no system can measure itself, which doesn't mean I can't see my arms, but it means the cat in the box cannot collapse its own wave function relative to the observer outside the box. The live cat cannot measure dead parts despite being in superposition of being dead and alive.

There are some options with problems, and I see that nobody has voted for any of them yet.
Most do not solve the problem of original cause of existence. I mean, my parents are my original cause of existence, but they don't solve the problem since their cause also needs explaining.

So for instance, "Some form of fundamental consciousness or god created the universe" lacks an explanation for the creator's existence. It is usually hand-waved away with the always-existed reply, but that just reduces that choice to the eternal model without a beginning, listed as a different choice.

Multiverse - universes “give birth to eachother” or all possibilities must exist. — Benj96

While a level 2 multiverse has this sort of property, as do some theories about black holes being those other universes, in both cases, there must still be a first cause, left unexplained.

Nothing is real. We live in some form of simulated universe

Living in a simulation would very much constitute being real, and it doesn't explain the origin of the simulation.

Big Bang - some singularity was the original cause. Physics once complete fulfills an explanation

The big bang theory is a theory of how the universe evolved from the dense singularity. It offers no explanation of the origin of that singularity.

Other options - please elaborate.

I take more of a relational view, like RQM (Rovelli). The question in the OP is meaningless as worded. Existence is a relation, not a property/predicate. Nice thing about that view is the problem you're pondering isn't a problem anymore. X exists relative to Y iff Y measures X. But there is no meaning to X exists or Y exists since it isn't expressed as a relation.

I've not read the whole thread, but responders are not always in accordance with physics. Mostly I see Tegmark's works countered with argument from incredulity, especially in the other thread that actually discusses MWI and level-4 universes. My interpretation of choice is probably RQM, not MWI.

MWI is unrelated to a level-1 multiverse. The argument that there are infinite copies of yourself seems to presume counterfactuals, which MWI does not, so right there Tegmark's stated preferences precludes the existence of an identical copy of yourself out there. So I will proceed under the premise of 1) a universe of infinite spatial extent, and 2) a quantum interpretation that supports counterfactuals, such as Bohmian mechanics.

I want to discuss his first type (I won't give my opinion about the other three as this probably gets me in trouble...). In an infinite universe, so Tegmark conjectures, there are infinite Hubble volumes and in this infinity an infinite of exact copies of you and me exist. — Cornwell1

Funny that it's worded that way. Hubble volumes have nothing to do with it. We can see objects that are currently outside our Hubble volume, so clearly those objects have a causal influence on us.

This can't be true because all Hubble volumes interact with their surroundings.

Fallicious reasoning. A given state (say current state of Earth) has a finite set of events in its past light cone, which was (as measured in proper distance) was merely the size of a grapefruit at the end of the inflation epoch, grew to a maximum proper size of nearly 6 billion light years around 7 billion years ago, and is today the size of Earth. By definition (and assuming cause and effect cannot happen faster than light), no event inside that past light cone can interact with an event inside that light cone.

So all we need for an identical Earth is for some finite volume of space (a similar light cone) out there with identical state. There are only a finite number of possible states for this finite volume, which Tegmark computes, hence there must be infinite copies given an infinite number of rolls of this finite sided die.

Suppose there is such a copy in a Hubble volume identical to the one we live in. How can this be? Near the border of our volume, there is interaction with stuff outside of the volume

Yes, which is why Hubble volume is useless. It affect the thing at the edge of the Hubble volume, but it doesn't effect you, so it matters not. Use past light cone instead of Hubble volume, and the logic works.

Tegmark's argument does not proceed along these my lines at all, and nor the one you describe. He does use a Hubble volume (like that matters. Only Earth matters). He computes that any finite volume can, at any given time, be only in some finite number of states. It's causal past is not considered. Since it is a current state, influence from the outside of the arbitrary volume is similarly moot. Infinite volumes divided by finite states makes for a vanishingly small probability of each state not appearing elsewhere.

which creates a difference between our volume and the identical volume somewhere else.

No it doesn't. It might mean that the identical (arbitrary) volume evolves subsequently differently, but that has no effect on the existence of the copy of you already at the center.

Am I right or am I left?
Worth a poll?

Polls get you opinions. The above is logic, not opinion.

Extra credit: Tegmark's argument (finite state possibilities of a given volume) is stronger than mine (worded from a causality standpoint). Can you point out why?

Personally (opinion here) I don't think there's an exact copy of me out there, but only because I don't accept all the premises I list above, not because the logic is faulty. I do accept the infinite spatial extent premise, without which the argument is meaningless. If it's finite at all, it's probably smaller than the insane large number that Tegmark computed for the nearest copy.

Been reading most of this thread without interfering, but this comment struck me wrong.

My intuitive sense is that people have no feel for what might be beyond the physical because they're instinctively oriented around the world of sensory detection - that only what can be sensed, weighed, measured by the senses or by scientific instruments is real. — Wayfarer

Only by physical instruments. Any physical instrument can serve as a scientific one, so maybe the distinction is unnecessary, but your choice of words seems to limit your thinking only to 'gadgetry', so to speak, as illustrated by your following comment:

Obviously today's scientific instruments are unthinkably powerful but people still have trouble understanding the sense that there might be some dimension or domain that is not available to apprehension by those means.

But the human body (among other things perhaps) is such a physical instrument, hardly 'unthinkably powerful' and yet you assert this other domain is available to it. That means a physical device (your body) is measuring this domain somewhere. All you have to do is investigate where, which is after all a scientific endeavor. Perhaps we can build a simple device that measures the same thing.

It is irrefutable that only a consciousness brings the wave function to collapse. — SolarWind

It is even more irrefutable that wave function collapse does not require consciousness. It seems that others are pointing this out. Wigner himself abandoned this interpretation when it was shown to logically lead to solipsism. Solipsism is another irrefutable thing.

Almost all quantum experiments take place without a human observer, except to gather the data afterwards.

What counts as an observer? — TiredThinker

Metaphysically, it is one system interacting with another, in any way.
Epistemologically, it seems to be a function of awareness, be it human or otherwise.

Can they use an electronic eye to see and record where the photon actually goes

You can't watch a photon. If you measure its path, any interference disappears.

and half the time delete the results before a human becomes aware of it

Human awareness does not play a metaphysical role (except in the Wigner interpretation). A result can be kept in superposition, but I know of no way to 'delete' a measured result.

I want to know if the electronic eye is interfering with the experiment and collapsing the wave function, or if it is awareness by a conscious human being.

The E-eye is not necessary either. Any interaction (the photon hitting the far wall in a room with no people or sensory devices) is enough to collapse the wave function, in interpretations with wave function collapse.

The guy didn't behave the same afterwards, whereas the zombie behaves indistinguishably from a 'human' in the same situation, so it doesn't really fit the definition.

Nice example though. Be interesting to have the dualists give their explanation of it. Somehow the surgery seems to have cut off the 'uplink' for 'mal-data' to wherever it gets 'processed' in a way that could be interpreted as pain. The data still gets through to say the rational area, but not to the area which causes distress. How might a dualist explain the 'mind' still getting the data for pain, but not feeling it? It's not like the mind was modified, only some connection in the brain.

Just for info, I do notice that there's multiple 'minds' in me. They hold different (contradictory even) beliefs, and one of the two is clearly in charge, but the other isn't epiphenomenal. But both of them seem physical. No funny external magic thingy.

User whatever terms you like, but your first person experiences of warmth, pain, color, etc. are not part of the physical descriptions of the world. — Marchesk

Your opinion is noted, but it provides negligible evidence falsifying an alternate one.

I find the p-zombie description not only possible, but a more accurate description of what's going on. A biological being such as you describe (with agency) would have evolved differently than what we see. Everybody tends to selection-bias that away. I did an old thread on the subject on the defunct PF. Can't reference it anymore. :sad:

Is the thermostat biologically equivalent to you? — Marchesk

Most thermostats are not biological, and are thus not the biological equivalent of anything.
I am, however, presenting one as a crude mechanical equivalent of "processing data which could be interpreted as 'feeling warmth'", which is what I claim noAx does.
Sorry for the 3rd person reference, but some of the prior posts have been getting a bit undefined as to what exactly 'I' refers. noAx is the physical biological human.

But this isn't about what words you can and can't use if you subscribe to this or that.

Yes it is. Chalmers forbids the usage of 'feels warmth' for the zombie, and the thermostat is a zombie, lacking the added bit that is the difference between zombies and humans. So the word is forbidden, despite the fact that the thermostat measures (via physics!) temperature and reacts to it, exactly as the zombie does. The vocabulary is reserved (by proponents of the existence of the ';additional bit') for objects that have that additional supernatural bit, as evidenced by assertions of 'lies' when the zombie claims that he also feels warmth.
I chose the thermostat since it is the ultimate in trivial data processing. A sensor and a single mercury switch is enough, the opposite end of the complexity spectrum compared to noAx, but fundamentally doing the same thing.
A rock also reacts to warmth, possibly by breaking, but it lacks both explicit sensor and an information processor, at least of the sort with which we're typically familiar.

It's about the fact that you do feel warmth.

Chalmers claims that the feeling of warmth can only be had by some supernatural experiencer, and since noAx is not one of those, noAx no more can feel warmth than can the thermostat. I refuse to be placed in a privileged category over it, unearned.

I tend to think [thermostats] are incapable of feeling warmth, although I wouldn't rule some form of panpsychism completely out.

Oooh, magic sauce!

I simply don't believe you when you claim skepticism about feeling warmth just because you can't say the same for thermostats in this discussion.

I'm merely skeptical of this immaterial experiencer/possessor, or of the magic sauce, or however it's presented. Surely I'm not the first person on these forums skeptical of dualism.

Of course they are. This is why they tend to say we have these properties, but these things over here, they don't. — InPitzotl

Don't or can't? This seems awfully begging to me.

if you had your name scratched onto the toaster when I stole it, it will tend to still be scratched on there unless I scratched it off.

Would it make it not the same toaster if the name got scratched off, or was never there in the first place? Despite my calling it a 'legal identity' (an old habit), I'm not talking about being able to prove the fact to a court of law. I'm talking about it actually being the toaster in question or not.
Perhaps 'pragmatic identity' fits better.

We might could even say certain arrangements of physical objects have privileged status, raising them above other arrangements.

That's not the story being pushed:

A zombie is physically identical to a normal human being, but completely lacks conscious experience.
— consc.net/zombies-on-the-web — InPitzotl

Per this assertion, the lack of privilege does not come from a defect or other difference in the physical arrangement.

The "I" I accused you of having is simply a unit of theory of mind as it applies to the linguistic aspect of your posts.

Not how I'm using it when I make a distinction. The "I" refers to the non-physical experiencer, the thing that gives the privilege.

You, OTOH, meet the requirements to apply theory of mind to as humans above the age of five regularly do.

Age of five eh? Does that imply you were a zombie until some sufficient age? What do you experience before then?

A computer can't tell you it's conscious? — frank

Only if someone conscious programs it to. — Janus

While there are plenty of computers running fixed algorithms that just play pre-recorded messages (a typical phone tree for instance), a true AI isn't programmed to say any specific words. It learns them, same as you do. Its programming may have been done by another computer, probably better than would have said 'conscious programer'. Your assertions are rapidly going to be demonstrated false as capabilties improve.

The "I" on the other hand refers to the experiencer of a conscious thing, something which gives it a true identity that doesn't supervene on the physical.
— noAxioms
I cry foul here. Imagine a believer of the classical elements telling you that he just fetched a pail of water from the well. When you ask the guy what water is, he explains that it is the element that is cold and wet. Analogously, you object... there is no "water"; for "water" refers to an element that is cold and wet, and we don't have such things. The problem is, the guy did in fact fetch the stuff from the well. This I believe is your error. — InPitzotl

This comment would perhaps at least make sense to me had it been attached to a comment of mine about pain and "data which could be interpreted as pain", but you've chosen to reference a comment about different kinds of identity for two very different things (a car and its driver say).
The only way I can parse it, it is the followers of Chalmers that are making the error you point out, where a human is privileged in being allowed to call something water/cold/wet, but anything else (a sump pump moving the stuff) doing the exact same thing is not allowed to use such privileged language (the pump moves a substance which could be interpreted as water). A mechanical device with damage sensors to which it reacts lacks the privilege to say it feels pain. I didn't make those privilege rules, so cry foul to the ones that make those rules. I decline to use the word because I don't consider myself to be in the privileged class.

Slightly more analytical, the guy has a bad theory of water. When asked to describe what water is, the guy would give you an intensional definition of water that is based on the bad theory. It's proper to correct the guy and to say that there is no such thing as he described in this case; however, the guy is also ostensively using the term... the stuff in the well is an example of what he means by water.

Bad analogy. In the case in question, nobody is ostensively using a term. You can't point to your subjective feeling of warmth and assert the toaster with thermostat doesn't feel anything analogous. Sure, it's a different mechanism, but not demonstrably fundamentally different.

So the guy is in a sense wrong about what water is, but is not wrong to have the concept of water.

No, wrong to have the concept of water since the term 'water' is not in fact being ostensively used. Perhaps not wrong, since there may be water in his well, but I detect none in mine and he cannot show me the water in his.

You're objecting to an intensional definition of "I".

I think so.

No, that's the legal 'me' doing that. Any toaster has one of those. Any automaton can type a similar response in a thread such as this.
— noAxioms
I've no idea what you mean by legal me

Legal identtiy: There is a rock placed at X, and you move it to a new location Y. Is it the same rock, or merely a different arrangement of matter in the universe with only language suggesting a binding between the prior arrangement and the later one? Is that toaster under your arm the same toaster as was stolen from me a moment ago, or a different one to which I have no claim? I shake a rope sending a wave down its length. Is the wave I created the same wave that reaches the other end despite not involving motion of a single bit of the original perturbed material? That's what I call legal identity, and has nothing to do specifically with life forms. It seems mostly language based, not based on anything physical, and it doesn't always work. A cell divides by mitosis. Which is the original cell? Language has no obvious answer and physics doesn't care.

but the ostensive I to which humans refer is not something a toaster has.

This seems to be an example of the privileged language mentioned above. What I see as the 'bad theory' asserts privileged status to humans, raising them above a mere physical arrangement of matter, and assigns language reserved only for objects with this privileged status. I'm denying the status, and thus sit in the group with the toaster, forbidden to use the sacred language. My son has one of those 'hey google' devices sitting on its table, and it might reply to a query with "I cannot find that song" or some such. But such usage seems to refer to the legal identity (something I don't deny) and not to "I, the experiencer of the device" which neither the toaster nor the physical arrangement of matter referred to as 'noAxioms'.

How far does you skepticism go? Do you think there's a strong possibility you're the only mind in existence? — RogueAI

I don't consider my position on this to be abnormally skeptical. I simply deny the non-physical experiencer, which is a fairly standard monist position. I differ from the mainstream position in that I'm willing for others to have the dual relationship (and hence all the talk about it), thus forcing me to use alternate terms to describe how I work. Most monists probably believe that every mind supervenes on the physical, not just some of them. My position explains why the zombies talk about pain when they don't actually 'feel' (privileged definition) it. They are not lying, merely drawing from the limited vocabulary available to them.

I any case, I'm confident you do feel pain, and trying to argue that you don't via some objective comparison or description doesn't change the fact that you do in fact feel pain. — Marchesk

Not if a mechanical device is forbidden from using the word. If a thermostat doesn't feel warmth, then neither do I. I admit to pain being a rare one, with few devices having sensors to provide it.

If the zombie can think it is conscious (which itself is an act of consciousness) , and this thinking is the result of brain activity, then why would consciousnesses not also be a result of brain activity? — Janus

:up:
Or not even necessarily brain activity, but any information-processing activity.

Thanks for all the feedback everyone. I actually appreciate it.

My brain hurts now. I'll admit to having difficulties with the p-zombie argument when it comes time for the zombies to talk about consciousness.
— Marchesk
Yeah, that's the real problem here. If qualia are epiphenomenal, how can we talk about them? — InPitzotl

Indeed, if one with qualia can talk about it, it isn't epiphenomenal. Those of us without the qualia might talk about it because we hear the rest of you talking about it and know no better.

Are you pretending for the thread, or do you actually think you're a p-zombie? — RogueAI

Well, not pretending anything. Chalmers claims a conscious experience that does not supervene logically on the physical. I don't have that since what I do isn't a logical contradiction like that. So I can only presume Chalmers (and the rest of you non-zombies) has a conscious experience that is fundamentally different than me just "receiving data that could be interpreted as pain", as it was put in T2. I might use the word pain, not because I (like the other zombies) am lying, but because we've been provided with no other vocabulary to describe it.

So you don't feel pain? — Marchesk

'Pain' seems to be a word reserved to describe the experience of had by the experiencer of a human. It would be a lie to say that I feel pain, in the context of this topic, so lacking an experiencer, I cannot by definition feel pain any more than can a robot with damage sensors. Again, I may use the word in casual conversation (outside the context of this topic) not because I'm lying, but because I lack alternative vocabulary to describe what the pure physical automaton does, something which by your definition cannot feel pain since it lacks this experiencer of it.

There's no 'I' (a thing with an identity say) that's being me.
— noAxioms
This phrase sounds suspicious. There's a me, but there's no I being me? — InPitzotl

This is a better question. The 'me' is like the robot, the thermostat', the automaton. These things, in common language, have a sort of legal identity, but not an identity which holds up to close scrutiny such as Parfit demonstrates. The "I" on the other hand refers to the experiencer of a conscious thing, something which gives it a true identity that doesn't supervene on the physical. My 'me' doesn't appear to have that. It seems inconsistent that something with an identity can be paired with something without one. The bijunction between the two doesn't work without a series of premises which I find totally implausible.

Also, there's definitely an "I" there. Something typed an entire grammatically correct, if not coherent, response in this thread with a unified theme conveying some particular form of skepticism to zombies.

No, that's the legal 'me' doing that. Any toaster has one of those. Any automaton can type a similar response in a thread such as this.

A self-driving car can't feel pain. I assume you can. — RogueAI

I don't feel pain. I'm a zombie, remember? I merely process the data received from my nerve endings and make the appropriate facial expressions and such.

Some cars don't have damage sensors. They're still awfully primitive. Ones that do have the sensors process the data, which can be interpreted as pain or not depending on your choice to characterize it with such language or not, a choice which doesn't alter what's actually going on one way or the other. But I assert there is no evidence of any fundamental difference between myself and the car. Our mutual refusal to use the word pain to describe the respective systems isn't evidence of anything.

What's that like? — Marchesk

To what? There isn't anything to which it is like something. That's the thing I deny. There's no 'I' (a thing with an identity say) that's being me.

So you see zombie colors, hear zombie sounds, think zombie thoughts, dream zombie dreams? — Marchesk

No, I see colors, hear sounds, think thoughts, and dream dreams, but I do it the zombie way without help from the outside, just like the self-driving car does. OK, the car probably doesn't dream, but it does the other things, however reluctant you might be to ascribe such terms to such a device.

There's nothing it's like to be a zombie. — Marchesk

I sort of agree, but see bold below. I have no evidence that anything is being me. But that doesn't mean that the zombie cannot function, perceive, etc. like any other automaton.

So for us humans switching places

I didn't really have in mind 'switching places' since lacking something being me, there's nothing to switch. Perhaps the zombie (Phil) can be possessed by something (Bob) being it for a short while. But this only lets Bob know what its like to be Phil (who is for a short while not a zombie), but Phil might not necessarily be aware of it.

the same thing experientially as being unconscious.

I think I follow this, but disagree. A self-driving car, with driver in it, has something 'being' it and the car is 'conscious'. The car is an extension (an avatar) of the driver. Not sure how you're using 'experience' here. A self-driving car is capable of being aware of its surroundings and function on its own. That's 'experience' in my book, as distinct from 'conscious' which is the experience and control of the driver. If you use the word differently, then I need one to describe what a mechanical device does to measure the world.

Point is, the car can cede control to a conscious entity (driver) and become a car/driver system, and if you ask the system if it has phenomenal experience, it would be the driver that answers 'yes'. Perhaps the car still has its own experience and notes that it would have done that lane change better, but it's not in control.
If the same car is driving itself with the same person now acting epiphenomenally as passenger, then there's still something 'being' it, but it's the car in control, and thus the car that answers when asked if it has phenomenal experience. The car is unaware of the passenger, so it truthfully answers yes since it is quite aware of the vehicles around it and such and has no driver-phenomenal experience with which to compare.
There may be no passenger at all, and thus nothing 'being' the system, and the experience of the car is the same. So as long as it is in control, the car is going to answer the same way. If it's under control of an external driver agent, then it is the agent that answers, not the car, and the car cannot convey what that experience is like.

I claim to be the zombie car, not the driver/car system because i have no evidence to the contrary and it seems more plausible than the physics-defying system otherwise posited.

a liar, ill educated, or mad person. — bert1

I am neither mad nor ill-educated.
Neither party is lying. For it to be a lie, each being (the zombie using nothing but physics, and the 'human', as y'all put it) need to spend a moment in each other's shoes to compare. This is what the one is like, and this is the other. Now given that, one can select which most closely matches his experience (or choose to lie about it and claim the other). Until then, there's no lie about it since both have only one experience to compare, and each has learned the vocabulary to describe it from places like this forum. I certainly would never have used the word 'qualia' for instance had I not heard it from others.
So in the interest of not lying, I assert that the experience that I have is just the result of doing it the same way as would any physical device with sensory input and an information processor to make sense of it. There's nothing seemingly inexplicable about it, and hence I conclude that I'm one of the zombies and that I'm missing out on the full inexplicable-by-physics experience.

Generically different entities have different evolutionary histories — InPitzotl

But at some point, there'd be a common ancestor, which means that a non-conscious entity bred a conscious one with this new relationship with the external entity.
In other words, what had functioned just fine in the parent (a mind that was self-contained and fit despite the lack of relationship with the 2nd entity) gave birth to one where all those advantages were cast aside, letting the choices be made by the external entity rather than itself as has been done by its parent.

This is probably unfair, since it paints a picture of a very binary, abrupt transition from one way of doing things to a complete new one. The child simply wasn't evolved to take advantage of the external entity, at least not in full, and so I imagine the process to take many generations, with a slow ceding of control to the external choices which for some reason made the phenomenal being more fit.

To me, this sounds like slow possession by a demon, however benevolent.

This also leaves the price paid by the parent (the extra metabolism to support an exceptionally large brain) still being paid by the child despite all the function of that expensive brain having been contracted out to a 3rd party. If the 3rd party is doing all the work, why still cart around a brain whose function can obviously be accomplished by one a 10th the metabolism as is done by other creatures our size.

If a machine with a ghost thinks it is not a machine with no ghost, it is correct. — bongo fury

In that case, it's probably the ghost thinking it's not a machine with no ghost, and the ghost is correct. The opinion of the machine is not given.

But anyone who takes this view will likely be an eliminativist — Pantagruel

Well, I've pretty much eliminated the immaterial mind as described by Chalmers, but the stanford page on eliminative materialism describes a 'radical position' which basic monism is not. I think my mental states supervene on physics, making me sort of materialist of sorts, hardly a radical position to take.
Functionalist about consciousness seems closer to the mark, but they don't call themselves zombies, and neither do I except in the context of discussions such as this one.

If one accepts that our immediate evidence does not rule out the possibility that we are zombies, then one should embrace the conclusion that we are zombies

The OP says they're functionally identical, so by definition, immediate evidence does not rule out the possibility.

But the reason there is a problem about consciousness is that our immediate evidence does rule out that possibility.

How is that a problem? It simply leaves it open to interpretation (as does any position without empirical differences).

If zombie-consciousness is devoid of phenomenality, what possible set of conditions could give rise to the zombie asserting phenomenality? — Pantagruel

I've always claimed to be the zombie, without lying about it. I don't think I'm conscious, at least not by Chalmers' definition, so no, they don't necessarily lie about it. Sure, I can detect red, but so can the simple mechanical device.

Sorry, I lack clarification here. I meant belief as in your belief of validity. Function as in, to invalidate another belief by using some evidence provided. — FlaccidDoor

OK, I see what you're saying. Some used to believe that light moved at a fixed speed through a medium, just as does sound. That was eventually shown to be false by experiment, so the theory was no longer valid, and thus any belief in it was not valid, at least not without some serious modifications.

It isn't? You have an example of something that contradicts neither itself nor empirical evidence that is nevertheless invalid?
— noAxioms

Let me start by clarifying that I don't intend to criticize your beliefs in particular at all.

Have you? I didn't really post to much of my actual beliefs, and I detected no criticism.

My example was to describe a scenario in which a person lives in a logically righteous world because they do not have the same strenuous validation process as you might. They can invalidate other beliefs because validation requires the belief to be his own. All other beliefs are invalid inherently according to this belief.

I didn't understand those last lines. How is the other person's belief (presumably in contradiction with the first person's) invalidated? What does "validation requires the belief to be his own" mean? I just don't see how my own beliefs can have any effect at all on the validity of somebody else's differing beliefs. I might believe they are wrong, but that belief doesn't invalidate theirs.

What do you think it means for a statement to be valid? I gave my definition above, but you seem to have a non-standard definition going on here.

I suspect that the reason you say this specific belief is invalid is because you are working on the belief that validation requires non-self-contradiction and supporting empirical evidence. While many people here will agree with you, including me, the unreasonable individual, as in the example given above, believes otherwise.

Umm.... What specific belief? Does this specific belief (perhaps by said unreasonable person) fail to meet my criteria?

Sorry, but maybe if I figured out what those phrases meant above, I'd figure out what you're trying to get at here.

the basis for invalidating a belief for you is that the belief must be self contradictory. — FlaccidDoor

or falsified by empirical evidence.

Additionally and also as you said, this belief has a weakness in that it needs evidence in order for it to function.

A belief seems not to require evidence, but evidence nevertheless helps.

I believe that is a reason why you struggle now. You believe that a non-self-contradicting perspective is a valid one.

It isn't? You have an example of something that contradicts neither itself nor empirical evidence that is nevertheless invalid?

A belief that invalidates all other beliefs inherently allows for a logically sound environment in which that person can reject all other beliefs without lying to themselves, regardless of whether that belief is based on truth or falsehoods.

I don't see how any belief can invalidate a different belief. I spelled out what does invalidate it, and alternate beliefs are not on the list.

I agree with your reasoning but there's a simple solution to it. That your belief includes believing that other beliefs are invalid. — FlaccidDoor

Doesn't follow. Say I believe in eternalism (block universe, time is a dimension) which is opposed to presentism (that there is a preferred moment in time). I have no reason to believe that the presentist stance is invalid. It is only invalid if it is self inconsistent or inconsistent with actual measurements somewhere, which it isn't (although I might choose to argue otherwise).
Maybe your point is that I have no grounds for my eternalist belief because I have no evidence that alternate views are unsound, but all beliefs are of that nature.

I do hold some beliefs (including some that I'm fairly certain are falsehoods), but I as far as I can manage, I don't claim these beliefs to be true knowledge since there seems to be no access to such knowledge.

Why is believing in falsehoods not the equivalent of interpreting it as truths? If you believe it is real, convince yourself it is real, then to that person it is as if that is a truth. — FlaccidDoor

Truth seems to not be something relative to a person or a belief, so despite the fact that I hold what I would label as 'beliefs', I'm not so naive to assert that those beliefs correspond to truth.

In my case, the things probably closest to truth are probably what I'd label as 'suspicions' rather than beliefs, and my strongest beliefs probably correspond to falsehoods. I find those beliefs useful to me. They make me fit for instance.

Maybe you define truth differently:

truth is a statement or idea describing reality as is.

With this definition, would there be falsehoods that are more useful than truths? — FlaccidDoor

What about belief in specific god X? There's a lot of mutually contradictory X's from which to choose, and some of them must be falsehoods, yet belief in them leads the believer into leading a better life (sometimes) and leads them to fit better into their local community, which is definitely beneficial.

Think of all the people with contradictory philosophies who are nevertheless completely convinced that they're the ones in the right, with everybody else being wrong. They're all lying to themselves, and believing the lies. Not lying that their view is the correct one, but lying that it must be the correct one. — noAxioms

Wouldn't lying necessitate that you "know" something else is true? — FlaccidDoor

You use the word 'know' like 'believe' here. One can believe something (be certain about it even, which is the lying to which I refer), but true knowledge is seemingly out of reach because there is not enough data. The existence of alternate valid interpretations of things means there is no way to know which interpretation (if any) is the true one. No, such lying is due not to knowing something else is true, but to realizing that something else could be true.

I can relate pretty heavily to that. My family is Christian and growing up I could never swallow the ideas they threw at me ...

Oh I swallowed it completely at first, and was put in a Christian school that taught that science (evolution in particular) didn't contradict the teachings of the church. But then other churches began to deny science and force a choice, so I looked at both as objectively as I could, and the choice was pretty obvious to me. I've been on a search ever since to identify the biases I never thought to question and it has led to some less than mainstream conclusions, but not conclusions so strong that I'll make the mistake of asserting them as truth. Just higher on the probability scale (fewest unanswerd problems) than any other interpretation I've considered.

I've come to terms with it recently with pragmatism, in that believing in those Christian things have usefulness to them.

My example above, yes. I wrote that before seeing this.
My first answer was more controversial and I abandoned it for this simpler case.

Aren't there believable lies and unbelievable truths? I guess my question is: can we know that we aren't believing in falsehoods? Can the liars you mention, be believing in falsehoods that they misinterpret as truths? — FlaccidDoor

Yes to all of these. Much of human nature (and certainly not limited to humans) is the preference to rationalize the truth we find convenient rather than rationally seek actual truth. Think of all the people with contradictory philosophies who are nevertheless completely convinced that they're the ones in the right, with everybody else being wrong. They're all lying to themselves, and believing the lies. Not lying that their view is the correct one, but lying that it must be the correct one.

I personally hold contradictory beliefs. I thus know that some of my beliefs cannot be correct, but one cannot simply will ones self to unbelieve something.

As for lies I tell others, I've never told my Mother that I've abandoned belief in God the way I was raised. What's the purpose in telling her that? She just doesn't need to worry that her child is going to hell, although I admit to having been at several funerals of vocal atheists where the mourners (and even the pastor) still comfort each other with words like "he's in a better place now", which is exactly a lie told for a purpose.

Can I then prove that I know this? — Cidat

Prove to who/what? Would not you need to know that I exist in order to prove your knowledge of something to me?

Sorry for long delay. I guess I sometimes go for quite some time without visiting the site.

What would the phrases, "living under a rock", or "living in a bubble" mean for an anti-realist? — Harry Hindu

Not claiming to be one, so I'll let them answer that. I make no claims of the unreality of anything.

Are there other minds, or other bodies?

I favor a relational stance (Rovelli), so I'd say that other people exist to me, and I to them. We measure each other, so each exists relative to the other. This has nothing at all to do with people, mind, consciousness or epistemology. I exist relative to my keyboard because it measures me (I have a causal effect on it). I do not exist relative to the current state of Betelgeuse since that 'system' has not measured me. I suppose I exist to some future state of Betelgeuse, but not necessarily any future state.

Per Rovelli, I do not exist relative to myself, which makes sense, and is essentially why Schrodinger's cat, perfectly capable of sensing its various parts, cannot collapse its own wave function relative to the outside of the closed box.

I favor such a view because it seems to avoid the general paradox of realism which is its inability to explain the reality of whatever the realist considers to be real.

so anti-realism defeats itself by rejecting it's own existence as a belief? A non-existent nihilist? :lol: — Harry Hindu

That's their claim it seems. They give meaning to the property of existence, but claim nothing has that property. I see little point in positing a property that nothing has, but other than that (and your wonderfully worded argument from incredulity aside), I see no contradiction in the stance, even if it isn't my stance.

What do you mean by, "'existence of an objective reality" to say that it is meaningless?

No relation specified, so the statement is meaningless in my view. For something to exist objectively, it would have to exist in relation to, what?... something more encompassing than the universe at least. The proverbial view from nowhere it seems. Is a member of the set of all that exists, except the set cannot list itself for the reason given above.

I am curious as to how the current density would have any influence on either the physical possibility of expansion, or the degree to which it occurs. In what way then are these two factors correlated, in particular? — Vessuvius

It goes a bit beyond my expertise, but density affects overall gravitational effect to the extent that sufficient density suffices to overcome the effects of dark energy. The gravitational epoch epoch ended some billions of years ago and the expansion reached a minimum. The average density is now low enough that dark energy has the greater effect. The Hubble 'constant' will eventually settle on an actual constant of about 57 km/sec/mpc which corresponds to exponential expansion as opposed to the nearly linear expansion of the last several billion years.

Good thought. Add to that, if you would; What does the vision of "multiple" contractions and expansions do if we focus on the velocity of (light in space) during these periods. — Don Wade

You mean a cyclic model? I'm not familiar with any such model that matches empirical evidence at the level of the accepted FLRW tunings. So I think you can make up any rules you want about what properties are preserved from one bang to the next.

Then the question of; how far does the universe contract before it starts to expand. Lots and lots of questions about the model.

I've never heard of a model that posits contraction that doesn't accelerate to some kind of crunch singularity. Doesn't mean such a model doesn't exist, but I've never heard of it.

unsatisfied in the case of a mass subject to an arbitrarily high-degree of compression — Vessuvius

Unsatisfied in the case of uniform distribution everywhere. The level of compression has nothing to do with it. The current density of the universe (about 6 protons per cubic meter) is enough to prevent expansion if it was that mass expanding into empty space. None of the material would have sufficient recession speed to exceed the escape velocity of the bounded mass that comprised the occupied part of the universe.

I do have one example against a 'bang from a location in otherwise empty space' which is that if such a thing occurred, all the mass of the universe would be compressed into a small space and would form a black hole, preventing any explosion (and shock wave) into said empty space.

On the other hand, an expansion of arbitrarily high compression of mass/energy (as posited by the BBT) would still involve a reasonably uniform distribution of mass and energy over all of spacetime, not at all meeting the stress energy tensor conditions of a black hole.

but as seen from the perspective of a fixed observer, relative to some far off point which is of so large a scale as to make the effects of such expansion dominate, for all intents and purposes it does appear to the observer as though a superluminal velocity is attained. — Vessuvius

The rate of increase in proper separation of a sufficiently distant (and visible) galaxy does indeed increase at a rate greater than c, but this still isn't superluminal since the light emitted by that galaxy in a direction away from us is moving away from us even faster. Nothing is outrunning any local light as you know.
The speeds expressed are relative to a non-inertial coordinate system and relativity theory doesn't forbid object or light from moving at speeds above c relative to a different kind of coordinate system, so none of this is particularly contradictory with anything.

Minkowski spacetime does contradict the geometry of the universe. Given Minkowski spacetime, light will eventually get from any location to any other. There are no event horizons. Not so with our universe, so Minkowski spacetime (typically assumed by any naive description of bang happening at a location and filling pre-existing empty space) cannot describe our universe.

Do notice how I qualified my statement with likening its chosen object only as appearance, rather than an absolute.

I did, but there's not much appearance to it. We see redshift and brightness, both of which approach infinity and zero respecitively with subluminal local motion, and from that glean the speed. If we wait long enough, we see the object get smaller over time, but not so much that it appears to move super fast. Take GN-z11 which at redshift z=11 is the most distant galaxy know. Yet it subtends an angle that places it only about 3 billion light years away, making it appear to move quite slowly actually. Speed from appearances is a calculation relative to a model and a coordinate system, not something that can be directly measured just by looking at it.
I think that under a Minkowski inertial frame, the most distant object visible would appear almost 7 billion light years away. I mapped the universe to such a coordinate system as best I could once. It almost works if expansion is uniform and not accelerating, but there's simply no way to work dark energy into it.

As my argument certainly wasn't that this reference frame is somehow privileged, or the only one of merit.

Good grief, I never caught a suggestion of that in your posts.

The purpose for which I cited it was instead to highlight how ideas of causality are meaningless in these cases because the light-cone of the observer is forever prevented from accessing the image of such distant point-sources, and nothing more.

You're talking about objects outside the visible universe? A few will become visible as that radius expands, but most never will. As a non-realist, I cannot say that any of those objects specifically exist relative to us, but someone positing an objective state of the entire universe would say that these distant objects do exist, any one of which is receding from us at an arbitrarily high rate.

Under all circumstances then, and unless the rate of expansion slows considerably enough to no longer appear superluminal — Vessuvius

Again, the expansion rate is expressed in different units and thus is not a speed and cannot be meaningfully compared using a word like 'superluminal'.

Then what is the universe? That is, something other than it started with a big bang. — Don Wade

A reasonable definition, but still dependent on serveral assumptions such as your chosen interpretation of QM. An MWI guy for instance might say that the universe is the one universal wave function. Any follower of a realist interpretation (MWI being one of them) might say that the universe is all that is. I learn towards the RQM side, but I'm hesitant to say the universe is all that I measure since that confines it to the visible universe, and it needs to be meaningful to talk about more distant things, however much those things don't relate to us.

Does the universe exist in space

No model supports that. It is a naive interpretation that is quickly falsified.

or does space exist in the universe?

Time as well since it is the same thing. Few can get their heads around time being part of the universe rather than the universe existing in time, which reduces its ontology to that of a mere object.

Which came first, space, or the universe?

Great example of trying to think of the universe as being contained by time. The universe is not an object. Spacetime is part of the structure that is the universe.

To the OP

If we first assume the universe started with a Big Bang, then there should have been a shock-wave extending out from the center. — Don Wade

The big bang theory does not posit an explosion into space from some point in that space. Any simple description on the web will tell you this. The expansion of the universe is not a speed, and is measured in different units. Pfhorrest seems to know the physics.

Science tells us that the shock-wave could not move faster than the speed of light. Did it?

Science says no such thing. It makes no mention of a shock wave, which is something you get from say a star exploding in space. The universe isn't an object in space like a star.

the diameter of the universe is about 90 billion light years — T Clark

The diameter of the visible part of the universe is about that. That volume includes all the material that can possibly ever have had a causal effect on us today. It doesn't mean we can see that far. Any light that has ever reached Earth up until the present has never been further from us than a proper distance of under 6 billion light years. Measured that way, the size of the visible universe is under a 6 BLY radius. We can only see these really distant galaxies because they were much closer than that distance back when they emitted the light that we're seeing now.

The title question assumes there is something. While I don't assume the opposite, I don't take it as an axiom that there is something. Thus I don't have to explain it, at least not first. Seems a question for realists. How do you explain the reality of whatever it is you consider real? Not my problem. Not a realist.