bunchberry

joined 2 months ago
[–] bunchberry@lemmy.world 2 points 1 month ago

Reading books on natural philosophy. By that I mean, not mathematics of the physics itself, but what do the mathematics actually tell us about the natural world, how to interpret it and think about it, on a more philosophical level. Not a topic I really talk to many people irl on because most people don't even know what the philosophical problems around this topic. I mean, I'd need a whole whiteboard just to walk someone through Bell's theorem to even give them an explanation to why it is interesting in the first place. There is too much of a barrier of entry for casual conversation.

You would think since natural philosophy involves physics that it would not be niche because there are a lot of physicists, but most don't care about the topic either. If you can plug in the numbers and get the right predictions, then surely that's sufficient, right? Who cares about what the mathematics actually means? It's a fair mindset to have, perfectly understandable and valid, but not part of my niche interests, so I just read tons and tons and tons of books and papers regarding a topic which hardly anyone cares. It is very interesting to read like the Einstein-Bohr debates, or Schrodinger for example trying to salvage continuity viewing a loss of continuity as a breakdown in classical notion of causality, or some of the contemporary discussions on the subject such as Carlo Rovelli's relational quantum mechanics or Francois-Igor Pris' contextual realist interpretation. Things like that.

It doesn't even seem to be that popular of a topic among philosophers, because most don't want to take the time to learn the math behind something like Bell's theorem (it's honestly not that hard, just a bit of linear algebra). So as a topic it's pretty niche but I have a weird autistic obsession over it for some reason. Reading books and papers on these debates contributes nothing at all practically beneficial to my life and there isn't a single person I know outside of online contacts who even knows wtf I'm talking about but I still find it fascinating for some reason.

[–] bunchberry@lemmy.world 1 points 2 months ago* (last edited 2 months ago) (2 children)

Why do you think consciousness remains known as the “hard problem”, and still a considered contentious mystery to modern science, if your simplistic ideas can so easily explain it?

You people really need to stop pretending like because one guy published a paper calling it the "hard problem" that it's somehow a deep impossible to solve scientific question. It's just intellectual dishonesty, trying to paint it as if it's equivalent to solving the problem of making nuclear fusion work or something.

It's not. And yes, philosophy is full of idiots who never justify any of their premises. David Chalmers in his paper where he calls it the "hard problem" quotes Thomas Nagel's paper as "proof" that experience is something subjective, and then just goes forward with his argument as if it's "proven," but Nagel's paper is complete garbage, and so nothing Chalmers argues beyond that holds any water, but is just something a lot of philosophers blindly accept even though it is nonsensical.

Nagel claims that the physical sciences don't incorporate point-of-view, and that therefore point-of-view must be a unique property of mammals, and that experience is point-of-view dependent, so experience too must come from mammals, and therefore science has to explain the origin of experience.

But his paper was wildly outdated when he wrote it. By then, we already had general relativity for decades, which is a heavily point-of-view dependent theory as there is no absolute space or time but its properties depend upon your point of view. Relational quantum mechanics also interprets quantum mechanics in a way that gets rid of all the weirdness and makes it incredibly intuitive and simple just with the singular assumption that the properties of particles depends upon point-of-view not that much different than general relativity with the nature of space and time, and so there is no absolute state of a system anymore.

Both general relativity and relational quantum mechanics not only treat reality as point-of-view dependent but tie itself back directly to experience: they tell you what you actually expect to observe in measurements. In quantum mechanics they are literally called observables, entities identifiable by their experiential properties.

Nagel is just an example of am armchair philosopher who does not engage with the sciences so he thinks they are all still Newtonian with some sort of absolute world independent of point-of-view. If the natural world is point-of-view dependent all the way down, then none of Nagel's arguments follow. There is no reason to believe point-of-view is unique to mammals, and then there is further no reason to think the point-of-view dependence of experience makes it inherently mammalian, and thus there is no reason to call experience "subjective."

Although I prefer the term "context" rather than "point-of-view" as it is more clear what it means, but it means the same thing. The physical world is just point-of-view dependent all the way down, or that is to say, context-dependent. We just so happen to be objects and thus like any other, exist in a particular context, and thus experience reality from that context. Our experiences are not created by our brains, experience is just objective reality from the context we occupy. What our brain does is think about and reflect upon experience (reality). It formulates experience into concepts like "red," "tree," "atom," etc. But it does not create experience.

The entire "hard" problem is based on a faulty premise based on science that was outdated when it was written.

If experience just is reality from a particular context then it makes no sense to ask to "derive" it as Chalmers and Nagel have done. You cannot derive reality, you describe it. Reality just is what it is, it just exists. Humans describe reality with their scientific theories, but their theories cannot create reality. That doesn't even make sense. All modern "theories of consciousness" are just nonsense as they all are based on the false premise that experience is not reality but some illusion created by the mammalian brain and that "true" reality is some invisible metaphysical entity that lies beyond all possible experience, and thus they demand we somehow need a scientific theory to show how this invisible reality gives rise to the visible realm of experience. The premise is just silly. Reality is not invisible. That is the nonsensical point of view.

[–] bunchberry@lemmy.world 2 points 2 months ago* (last edited 2 months ago)

You should look into contextual realism. You might find it interesting. It is a philosophical school from the philosopher Jocelyn Benoist that basically argues that the best way to solve most of the major philosophical problems and paradoxes (i.e. mind-body problem) is to presume the natural world is context variant all the way down, i.e. there simply is no reality independent of specifying some sort of context under which it is described (kind of like a reference frame).

The physicist Francois-Igor Pris points out that if you apply this thinking to quantum mechanics, then the confusion around interpreting it entirely disappears, because the wave function clearly just becomes a way of accounting for the context under which an observer is observing a system, and that value definiteness is just a context variant property, i.e. two people occupying two different contexts will not always describe the system as having the same definite values, but may describe some as indefinite which the other person describes as definite.

"Observation" is just an interaction, and by interacting with a system you are by definition changing your context, and thus you have to change your accounting for your context (i.e. the wave function) in order to make future predictions. Updating the wave function then just becomes like taring a scale, that is to say, it is like re-centering or "zeroing" your coordinate system, and isn't "collapsing" anything physical. There is no observer-dependence in the sense that observers are somehow fundamental to nature, only that systems depend upon context and so naturally as an observer describing a system you have to take this into account.

[–] bunchberry@lemmy.world 1 points 2 months ago* (last edited 2 months ago) (1 children)

Quantum mechanics is incompatible with general relativity, it is perfectly compatible with special relativity, however. I mean, that is literally what quantum field theory is, the unification of special relativity and quantum mechanics into a single framework. You can indeed integrate all aspects of relativity into quantum mechanics just fine except for gravity. It's more that quantum mechanics is incompatible with gravity and less that it is incompatible with relativity, as all the other aspects we associate with relativity are still part of quantum field theory, like the passage of time being relative, relativity of simultaneity, length contraction, etc.

[–] bunchberry@lemmy.world 1 points 2 months ago

There shouldn’t be a distinction between quantum and non-quantum objects. That’s the mystery. Why can’t large objects exhibit quantum properties?

What makes quantum mechanics distinct from classical mechanics is the fact that not only are there interference effects, but statistically correlated systems (i.e. "entangled") can seem to interfere with one another in a way that cannot be explained classically, at least not without superluminal communication, or introducing something else strange like the existence of negative probabilities.

If it wasn't for these kinds of interference effects, then we could just chalk up quantum randomness to classical randomness, i.e. it would just be the same as any old form of statistical mechanics. The randomness itself isn't really that much of a defining feature of quantum mechanics.

The reason I say all this is because we actually do know why there is a distinction between quantum and non-quantum objects and why large objects do not exhibit quantum properties. It is a mixture of two factors. First, larger systems like big molecules have smaller wavelengths, so interference with other molecules becomes harder and harder to detect. Second, there is decoherence. Even small particles, if they interact with a ton of other particles and you average over these interactions, you will find that the interference terms (the "coherences" in the density matrix) converge to zero, i.e. when you inject noise into a system its average behavior converges to a classical probability distribution.

Hence, we already know why there is a seeming "transition" from quantum to classical. This doesn't get rid of the fact that it is still statistical in nature, it doesn't give you a reason as to why a particle that has a 50% chance of being over there and a 50% chance of being over here, that when you measure it and find it is over here, that it wasn't over there. Decoherence doesn't tell you why you actually get the results you do from a measurement, it's still fundamentally random (which bothers people for some reason?).

But it is well-understood how quantum probabilities converge to classical probabilities. There have even been studies that have reversed the process of decoherence.

[–] bunchberry@lemmy.world 4 points 2 months ago* (last edited 2 months ago)

Yes, the problem with quantum mechanics is it's not just your Deepak Chopras of the world that get sucked into quantum woo, but even a lot of respectable academics with serious credentials, thus giving credence to these ideas. Quantum mechanics is a context-dependent theory, the properties of systems are context variant. It is not observer-dependent. The observer just occupies their own unique context and since it is context-dependent, they have to describe things from their own context.

It is kind of like velocity in Galilean relativity, you have to take into account reference frame. Two observers in Galilean relativity could disagree on certain things, such as the velocity of an object but the disagreement is not "confusing" because if you understand relativity, you'd know it's just a difference in reference frame. Nothing important about "observers" here.

I do not understand what is with so many academics in fully understanding that properties of systems can be variant under different reference frames in special relativity, but when it comes to quantum mechanics their heads explode trying to interpret the contextual nature of it and resort to silly claims like saying it proves some fundamental role for the conscious observer. All it shows is that the properties of systems are context variant. There is nothing else.

Once you accept that, then everything else follows. All of the unintuitive aspects of quantum mechanics disappear, you do not need to posit systems in two places at once, some special role for observers, a multiverse, nonlocality, hidden variables, nothing. All the "paradoxes" disappear if you just accept the context variance of the states of systems.

[–] bunchberry@lemmy.world 2 points 2 months ago* (last edited 2 months ago)

For the first question, I would recommend reading the philosopher and physicist Francois-Igor Pris who not only seems to understand the deep philosophical origins of the problem, but also provides probably the simplest solution to it. Pris points out that we cannot treat the philosophical ramification in isolation, as if the difficulty in understanding quantum physics originates from quantum physics itself. It must originate from a framework in which we are trying to apply to quantum physics that just breaks down, and therefore it must originate from preconceived philosophical notions people have before even learning of quantum physics.

In other words, you have to go back to the drawing board, question very foundational philosophical notions. He believes that it originates from the belief in metaphysical realism in the traditional sense, which is the idea that there is an objective reality but it is purely metaphysical, i.e. entirely invisible because what we perceive is merely an illusion created by the conscious mind, but somehow it is given rise to by equivalent objects that are impossible to see. For example, if you have a concept of a rock in your mind, that concept "reflects" a rock that is impossible to see, what Kant had called the thing-in-itself. How can a reality that is impossible to observe ever "give rise to" what we observe? This is basically the mind-body problem.

Most academics refuse to put forward a coherent answer to this, and in a Newtonian framework it can be ignored. This problem resurfaces in quantum physics, because you have the same kind of problem yet again. What is a measurement if not an observation, and what is an observation if not an experience? You have a whole world of invisible waves floating around in Hilbert space that suddenly transform themselves into something we can observe (i.e. experience) the moment we attempt to look at them, i.e. they transform themselves suddenly into observable particles in spacetime the moment we look.

His point is ultimately that, because people push off coming up with a philosophical solution to the mind-body problem, when it resurfaces as the measurement problem, people have no idea how to even approach it. However, he also points out that any approach you do take ultimately parallels whatever solution you would take to the mind-body problem.

For example, eliminative materialists say the visible world does not actually exist but only the nonvisible world and that our belief we can experience things is an illusion. This parallels the Many Worlds Interpretation which gets rid of physical particles and thus gets rid of all observables and only has waves evolving in Hilbert space without observables. Idealists argue in favor of getting rid of invisible reality and just speak of the mind, which if you read the philosophical literature you will indeed find a lot of academics who are idealists who try to justify it with quantum mechanics.

Both of these positions are, in my view, problematic, and I like Pris' his own solution based on Jocelyn Benoist's philosophy of contextual realism which is in turn based off of Ludwig Wittgenstein's writings. Benoist has written extensively against all the arguments claiming that reality is invisible and has instead argued that what we experience is objective reality as it is exists independent of the observer but dependent upon the context of the observation. Thus he is critical of pretty much all of modern philosophers who overwhelmingly adhere either to metaphysical realism or to idealism. There is no mind-body problem under this framework because reality was never invisible to begin with, so there is no "explanatory gap."

Apply this thinking to quantum mechanics then it also provides a solution to the measurement problem that is probably the simplest and most intuitive and is very similar to Carlo Rovelli's interpretation. Reality depends upon context all the way down, meaning that the properties of systems must be context variant. And that's really the end of the story, no spooky action at a distance, no multiverse, no particles in two places at once, no language of observer-dependence, etc.

Whenever you describe physical reality, you have to pick a coordinate system as reality depends upon context and is not "absolute," or as Rovelli would say, reality depends upon the relations of a system to every other system. Hence, if you want to describe a system, you have to pick a coordinate system under which it will be "observed," kind of like a reference frame, but the object you choose as the basis of the coordinate system has to actually interact with the other object. The wave function then is just a way for accounting for the system's context as it incorporates the relations between the system being used as the basis of the reference frame and the object that it will interact with.

Basically, it is not much different from Copenhagen, except "observer-dependence" is replaced by "context-dependence" as the properties of systems are context variant and any physical system, even a rock, can be used as the basis of the coordinate system. But, of course, if you want to predict what you will observe, then you always implicitly use your own context as the basis of the coordinate system. This is a realist stance, but not a metaphysical realist stance, because the states of particles are not absolute, there is no thing-in-itself, and the reality is precisely what you perceive and not some waves in Hilbert space beyond it (these are instead treated as tools for predicting what the value will be when you measure it, and not itself an entity). Although, it is only whether or not they have a property at all that is context variant.

If two observers have interacted with the same particle, they will agree as to its state, as you do not get disagreements of the actual values of those particles, only whether or not they have a state at all. They would not be verbal disagreements either, because if an observer measures the state of a particle then goes and tells it to someone else, then it also indirectly enters their context as they would become correlated with that particle through their friend. You only get disagreements if there is no contact. For example, Wigner's friend paradox, where his friend has measured the particle but has not told him the results nor has he measured it himself, from his context it would indeed have no state.

The "collapse" would then not be a collapse of a physical "wave" but, again, reality is context variant, and so if you interact with a system, then it changes your relation to it, so you have to update the wave function to account for a change in context, kind of like if you change your reference frame in Galilean relativity. Everything is interpreted through this lens whereby nature is treated as context variant in this way, and it resolves all the paradoxes without introducing anything else. So if you can accept that one premise then everything else is explained. By abandoning metaphysical realism, it also simultaneously solves the other philosophical problems that originate from that point of view, i.e. the "hard problem" does not even make sense in a contextual realist framework and is not applicable.

[–] bunchberry@lemmy.world 2 points 2 months ago* (last edited 2 months ago)

Yes, there are a lot of intuitive understandings in the literature if you're willing to look for it. The problem is that most people believe in a Newtonian view of the world which just is not compatible with quantum physics, so it requires you to alter some philosophical beliefs, and physics professors don't really want to get into philosophical arguments, so it's not really possible to reach a consensus on the question in physics departments. Even worse, there's rarely a consensus on anything if you go to the philosophy department. So it's not really that there are not very simple and intuitive ways to understand quantum mechanics, it's that it's not possible to get people to agree upon a way to interpret it, so there is a mentality to just avoid interpretation at all so that students don't get distracted from actually understanding the math.

[–] bunchberry@lemmy.world 2 points 2 months ago

That's actually not quite accurate, although that is how it is commonly interpreted. The reason it is not accurate is because Bell's theorem simply doesn't show there is no hidden variables and indeed even Bell himself states very clearly what the theorem proves in the conclusion of his paper.

In a theory in which parameters are added to quantum mechanics to determine the results of individual measurements, without changing the statistical predictions, there must be a mechanism whereby the setting of one measuring device can influence the reading of another instrument, however remote. Moreover, the signal involved must propagate instantaneously, so that such a theory could not be Lorentz invariant.[1]

In other words, you can have hidden variables, but those hidden variables would not be Lorentz invariant. What is Lorentz invariance? Well, to be "invariant" basically means to be absolute, that is to say, unchanging based on reference frame. The term Lorentz here refers to Lorentz transformations under Minkowski space, i.e. the four-dimensional spacetime described by special relativity.

This implies you can actually have hidden variables under one of two conditions:

  1. Those hidden variables are invariant under some other framework that is not special relativity, basically meaning the signals would have to travel faster than light and thus would contradict special relativity and you would need to replace it with some other framework.
  2. Those hidden variables are variant. That would mean they do indeed change based on reference frame. This would allow local hidden variable theories and thus even allow for current quantum mechanics to be interpreted as a statistical theory in a more classical sense as it even evades the PBR theorem.[2]

The first view is unpopular because special relativity is the basis of quantum field theory, and thus contradicting it would contradict with one of our best theories of nature. There has been some fringe research into figuring out ways to reformulate special relativity to make it compatible with invariant hidden variables,[3] but given quantum mechanics has been around for over a century and nobody has figured this out, I wouldn't get your hopes up.

The second view is unpopular because it can be shown to violate a more subtle intuition we all tend to have, but is taken for granted so much I'm not sure if there's even a name for it. The intuition is that not only should there be no mathematical contradictions within a single given reference frame so that an observer will never see the laws of physics break down, but that there should additionally be no contradictions when all possible reference frames are considered simultaneously.

It is not physically possible to observe all reference frames simulatenously, and thus one can argue that such an assumption should be abandoned because it is metaphysical and not something you can ever observe in practice.[4] Note that inconsistency between all reference frames considered simulatenously does not mean observers will disagree over the facts, because if one observer asks another for information about a measurement result, they are still acquiring information about that result from their reference frame, just indirectly, and thus they would never run into a disagreement in practice.

However, people still tend to find it too intuitive to abandon this notion of simultaneous consistency, so it remains unpopular and most physicists choose to just interpret quantum mechanics as if there are no hidden variables at all. #1 you can argue is enforced by the evidence, but #2 is more of a philosophical position, so ultimately the view that there are no hidden variables is not "proven" but proven if you accept certain philosophical assumptions.

There is actually a second way to restore local hidden variables which I did not go into detail here which is superdeterminism. Superdeterminism basically argues that if you did just have a theory which describes how particles behave now but a more holistic theory that includes the entire initial state of the universe going back to the Big Bang and tracing out how all particles evolved to the state they are now, you can place restrictions on how that system would develop that would such that it would always reproduce the correlations we see even with hidden variables that is indeed Lorentz invariant.

Although, the obvious problem is that it would never actually be possible to have such a theory, we cannot know the complete initial configuration of all particles in the universe, and so it's not obvious how you would derive the correlations between particles beforehand. You would instead have to just assume they "know" how to be correlated already, which makes them equivalent to nonlocal hidden variable theories, and thus it is not entirely clear how they could be made Lorentz invariant. Not sure if anyone's ever put forward a complete model in this framework either, same issue with nonlocal hidden variable theories.

[–] bunchberry@lemmy.world 2 points 2 months ago

So… there are things that are either within the category of thought or not?

Objects are in the category of thought but not in some spatial "realm" or "world" of thought. It is definitional, linguistic, not a statement about ontology.

Is thought mutually exclusive to material? Is thought composed of material or the other way around? Or are they both the same?

From an a priori standpoint there is no material, there is just reality. Our understanding of material reality comes from an a posteriori standpoint of investing it, learning about it, forming laws etc, and we do come to understand thought from an a posteriori lens as something that can be observed and implemented in other systems.

Usually thought itself is not even considered as part of the so-called "hard problem" as that's categorized into the "easy problem."

That is the standard definition of idealism, is it not? That existence is immaterial?

They say existence is "mind" which includes both thought and experience which they both argue are products of the mind, and so if we start off with thought and experience as the foundations of philosophy then we're never able to leave the mind. That's how idealism works, the "thought" part of basically the "easy" problem and the "experience" part is what entails the "hard" problem since even idealists would concede that it is not difficult to conceive of constructing an intelligent machine that can reason, potentially even as good as humans can.

[–] bunchberry@lemmy.world 11 points 2 months ago (1 children)
[–] bunchberry@lemmy.world 4 points 2 months ago (1 children)

well IBM does have cloud accessible quantum computers that they don't charge to use

I used those to teach myself some stuff about quantum information science

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