What is it then? If you say it’s a wave, well, that wave is in Hilbert space which is infinitely dimensional, not in spacetime which is four dimensional, so what does it mean to say the wave is “going through” the slit if it doesn’t exist in spacetime? Personally, I think all the confusion around QM stems from trying to objectify a probability distribution, which is what people do when they claim it turns into a literal wave.

To be honest, I think it’s cheating. People are used to physics being continuous, but in quantum mechanics it is discrete. Schrodinger showed that if you take any operator and compute a derivative, you can “fill in the gaps” in between interactions, but this is just purely metaphysical. You never see these “in between” gaps. It’s just a nice little mathematical trick and nothing more. Even Schrodinger later abandoned this idea and admitted that trying to fill in the gaps between interactions just leads to confusion in his book Nature and the Greeks and Science and Humanism.

What’s even more problematic about this viewpoint is that Schrodinger’s wave equation is a result of a very particular mathematical formalism. It is not actually needed to make correct predictions. Heisenberg had developed what is known as matrix mechanics whereby you evolve the observables themselves rather than the state vector. Every time there is an interaction, you apply a discrete change to the observables. You always get the right statistical predictions and yet you don’t need the wave function at all.

The wave function is purely a result of a particular mathematical formalism and there is no reason to assign it ontological reality. Even then, if you have ever worked with quantum mechanics, it is quite apparent that the wave function is just a function for picking probability amplitudes from a state vector, and the state vector is merely a list of, well, probability amplitudes. Quantum mechanics is probabilistic so we assign things a list of probabilities. Treating a list of probabilities as if it has ontological existence doesn’t even make any sense, and it baffles me that it is so popular for people to do so.

This is why Hilbert space is infinitely dimensional. If I have a single qubit, there are two possible outcomes, 0 and 1. If I have two qubits, there are four possible outcomes, 00, 01, 10, and 11. If I have three qubits, there are eight possible outcomes, 000, 001, 010, 011, 100, 101, 110, and 111. If I assigned a probability amplitude to each event occurring, then the degrees of freedom would grow exponentially as I include more qubits into my system. The number of degrees of freedom are unbounded.

This is exactly how Hilbert space works. Interpreting this as a physical infinitely dimensional space where waves really propagate through it just makes absolutely no sense!

It is only continuous because it is random, so prior to making a measurement, you describe it in terms of a probability distribution called the state vector. The bits 0 and 1 are discrete, but if I said it was random and asked you to describe it, you would assign it a probability between 0 and 1, and thus it suddenly becomes continuous. (Although, in quantum mechanics, probability amplitudes are complex-valued.) The continuous nature of it is really something epistemic and not ontological. We only observe qubits as either 0 or 1, with discrete values, never anything in between the two.

OrchOR makes way too many wild claims for there to easily be any evidence for it. Even if we discover quantum effects (in the sense of scalable interference effects which have absolutely not been demonstrated) in the brain that would just demonstrate there are quantum effects in the brain, OrchOR is filled with a lot of assumptions which go far beyond this and would not be anywhere near justified. One of them being its reliance on gravity-induced collapse, which is nonrelativistic, meaning it cannot reproduce the predictions of quantum field theory, our best theory of the natural world.

A theory is ultimately not just a list of facts but a collection of facts under a single philosophical interpretation of how they relate to one another. This is more of a philosophical issue, but even if OrchOR proves there is gravitational induced collapse and that there is quantum effects in the brain, we would still just take these two facts separately. OrchOR tries to unify them under some bizarre philosophical interpretation called the Penrose–Lucas argument that says because humans can believe things that are not proven, therefore human consciousness must be noncomputable, and because human consciousness is not computable, it must be reducible to something that you cannot algorithmically predict its outcome, which would be true of an objective collapse model. Ergo, wave function collapse causes consciousness.

Again, even if they proved that there is scalable quantum interference effects in the brain, even if they proved that there is gravitationally induced collapse, that alone does not demonstrate OrchOR unless you actually think the Penrose-Lucas argument makes sense. They would just be two facts which we would take separately as fact. It would just be a fact that there is gravitionally induced collapse, a fact that there is scalable quantum interference effects in the brain but there would be no reason to adopt any of their claims about “consciousness.”

But even then, there is still no strong evidence that the brain in any way makes use of quantum interference effects, only loose hints that it may or not be possible with microtubules, and there is definitely no evidence of the gravitationally induced collapse.

Both these figures are embarrassingly bad.

Hoffman confuses function for perception and constantly uses arguments demonstrating things can interpret reality incorrectly (which is purely a question of function) in order to argue they cannot perceive reality “as it is.,” which is a huge non-sequitur. He keeps going around promoting his “theorem” which supposedly “proves” this yet if you read his book where he explains his theorem it is again clearly about function as his theorem only shows that limitations in cognitive and sensory capabilities can lead something to interpret reality incorrectly yet he draws a wild conclusion which he never justifies that this means they do not perceive reality “as it is” at all.

Kastrup is also just incredibly boring because he never reads books so he is convinced the only two philosophical schools in the universe are his personal idealism and metaphysical realism, which the latter he constantly incorrectly calls “materialism” when not all materialist schools of thought are even metaphysically realist. Unless you are yourself a metaphysical realist, nothing Kastrup has ever written is interesting at all, because he just pretends you don’t exist.

Metaphysical realism is just a popular worldview in the west that most Laymen tend to naturally take on unwittingly. If you’re a person who has ever read books in your life, then you’d quickly notice that attacking metaphysical realism doesn’t get you to idealism, at best it gets you to metaphysical realism being not a coherent worldview… which that is the only thing I agree with Kastrup with.

Classical computers compute using 0s and 1s which refer to something physical like voltage levels of 0v or 3.3v respectively. Quantum computers also compute using 0s and 1s that also refers to something physical, like the spin of an electron which can only be up or down. Although these qubits differ because with a classical bit, there is just one thing to “look at” (called “observables”) if you want to know its value. If I want to know the voltage level is 0 or 1 I can just take out my multimeter and check. There is just one single observable.

With a qubit, there are actually three observables: σ_x, σ_y, and σ_z. You can think of a qubit like a sphere where you can measure it along its x, y, or z axis. These often correspond in real life to real rotations, for example, you can measure electron spin using something called Stern-Gerlach apparatus and you can measure a different axis by physically rotating the whole apparatus.

How can a single 0 or 1 be associated with three different observables? Well, the qubit can only have a single 0 or 1 at a time, so, let’s say, you measure its value on the z-axis, so you measure σ_z, and you get 0 or 1, then the qubit ceases to have values for σ_x or σ_y. They just don’t exist anymore. If you then go measure, let’s say, σ_x, then you will get something entirely random, and then the value for σ_z will cease to exist. So it can only hold one bit of information at a time, but measuring it on a different axis will “interfere” with that information.

It’s thus not possible to actually know the values for all the different observables because only one exists at a time, but you can also use them in logic gates where one depends on an axis with no value. For example, if you measure a qubit on the σ_z axis, you can then pass it through a logic gate where it will flip a second qubit or not flip it because on whether or not σ_x is 0 or 1. Of course, if you measured σ_z, then σ_x has no value, so you can’t say whether or not it will flip the other qubit, but you can say that they would be correlated with one another (if σ_x is 0 then it will not flip it, if it is 1 then it will, and thus they are related to one another). This is basically what entanglement is.

Because you cannot know the outcome when you have certain interactions like this, you can only model the system probabilistically based on the information you do know, and because measuring qubits on one axis erases its value on all others, then some information you know about the system can interfere with (cancel out) other information you know about it. Waves also can interfere with each other, and so oddly enough, it turns out you can model how your predictions of the system evolve over the computation using a wave function which then can be used to derive a probability distribution of the results.

What is even more interesting is that if you have a system like this where you have to model it using a wave function, it turns out it can in principle execute certain algorithms exponentially faster than classical computers. So they are definitely nowhere near the same as classical computers. Their complexity scales up exponentially when trying to simulate quantum computers on a classical computer. Every additional qubit doubles the complexity, and thus it becomes really difficult to even simulate small numbers of qubits. I built my own simulator in C and it uses 45 gigabytes of RAM to simulate just 16. I think the world record is literally only like 56.

I feel like there is a pretty big gap between understanding how logic gates and truth tables work and understanding the underlying physics of how modern processors work.

Even if you believe there really exists a “hard problem of consciousness,” even Chalmers admits such a thing would have to be fundamentally unobservable and indistinguishable from something that does not have it (see his p-zombie argument), so it could never be something discovered by the sciences, or something discovered at all. Believing there is something immaterial about consciousness inherently requires an a priori assumption and cannot be something derived from a posteriori observational evidence.

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.

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.

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.

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.

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.

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.

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.

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.

french?

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

They’re just categorically different, there isn’t an “inside” or an “outside” in the sense of spatial structure as that is something derived a posteriori as part of thought.

I’m not sure what it would even mean to say reality is “thought”. If I try my best to stop thinking about things does experiential reality just disappear? Not for me it doesn’t. Maybe for you.

You shouldn’t take it that seriously. MWI has a lot of zealots in the popular media who act like it’s a proven fact, kind of like some String Theorists do, but it is actually rather dubious.

MWI claims it is simpler because they are getting rid of the Born rule, so it has less assumptions, but the reason there is the Born rule in QM is because… well, it’s needed to actually predict the right results. You can’t just throw it out. It’s also impossible to derive the Born rule without some sort of additional assumption, and there is no agreed upon way to do this.[1]

This makes MWI actually more complicated than traditional quantum mechanics because they have to add different arbitrary assumptions and then add an additional layer of mathematics to derive the Born rule from it, rather than assuming it. These derivations also tend to be incredibly arbitrary because the assumptions you have to make to derive it are always chosen specifically for the purpose of deriving the Born rule and don’t seem to make much sense otherwise, and thus are just as arbitrary as assuming the Born rule directly.[2] [3]

If you prefer a video, the one below discusses various “multiverse” ideas including MWI and also discusses how it ultimately ends up being more mathematically complicated than other interpretations of QM.

https://www.youtube.com/watch?v=QHa1vbwVaNU

MWI also makes no sense for a separate reason. If you consider the electromagnetic field for example, how do we know it exists? We know it exists because we can see its effect on particles. If you drop some iron filings around a magnet, it conforms to the shape of a field, but ultimately what you are seeing is the iron filings and not the field itself, but the effects of the field. Now, imagine if someone claimed the iron filings don’t even exist, only the field. You’d be a bit confused because, well, you only know the field exists because of its effects on the filings. You can’t see the field, only the particles, so if you deny the particles, then you’re just left in confusion.

This is effectively what MWI does. We live in a world composed of spacetime containing particles, yet wave functions describe, well, waves made of nothing that exist in an abstract space known as Hilbert space. Schrodinger’s derivation of his famous wave equation is based on observing the behavior of particles. MWI denies particles even exist and everything is just waves in Hilbert space made of nothing, which is very bizarre because then you would be effectively claiming the entire universe is composed of something entirely invisible. So how does that explain everything we see?

[I]t does not account, per se, for the phenomenological reality that we actually observe. In order to describe the phenomena that we observe, other mathematical elements are needed besides ψ: the individual variables, like X and P, that we use to describe the world. The Many Worlds interpretation does not explain them clearly. It is not enough to know the ψ wave and Schrödinger’s equation in order to define and use quantum theory: we need to specify an algebra of observables, otherwise we cannot calculate anything and there is no relation with the phenomena of our experience. The role of this algebra of observables, which is extremely clear in other interpretations, is not at all clear in the Many Worlds interpretation.

--- Carlo Rovelli, Helgoland: Making Sense of the Quantum Revolution

The philosopher Tim Maudlin has a whole lecture you can watch below on this problem, pointing out how MWI makes no sense because nothing in the interpretation includes anything we can actually observe. It quite literally describes a whole universe without observables.

https://www.youtube.com/watch?v=us7gbWWPUsA

Not to rain on your parade or anything if you are just having fun, but there is a lot of misinformation on websites like YouTube painting MWI as more reasonable than it actually is, so I just want people to be aware.

What is thought of as opposed to thought itself must necessarily exist prior to the thought in order for it to enter into thought and be what is thought of in the first place. I mean, it’s just self-evident, is it not? If all thoughts cease, reality doesn’t disappear. It’s always there independent of whether or not thought is applied to it or not, whether or not there is an attempt to interpret it. It exists independent of any attempt made to formulate a subjective interpretation of it. That’s all that is meant here by “objective,” that reality is what it is entirely independent of what it is subjectively taken to be.