When you imagine a fair coin being flipped and describing that with a probabilistic mathematical model, you can always imagine a classical story of what actually occurred. How you went from a spread out of possibilities to witnessing a single definite outcome. So I can understand the ontology because there is a classical ontology.

What QM is forcing us to do is write down as much classical story as possible, THEN SOMETHING TRULY RANDOM OCCURS. I can't imagine in my head any possible classical story. Both the coin and quantum "measurement" use probability theory in a similar way, but this is an important distinction.

When you say develop a new ontology, I really think you mean develop a recipe. I see no way to even comprehend anything but classical ontologies. I'm not sure if it's a limit of our, biology, imagination, or intuition. There is no classical ontology, nor settled ontology for that matter to describe the "measurement" of superpositions process.

You can't simulate that (fundamental randomness) purely classically. The classical world can be simulated with Turing machines, however. And we know infinite pen-and-paper maths can simulate any Turing machine.

How do I get from pen-and-paper maths (doing simple turing-machine-like operations/computations) to a truly random event, a necessary component for a quantum measurement? So when I'm doing my pen-and-paper maths, I have to go grab a radioactive atom and use the time it decays to somehow seed a random event into my simulation.

I do not know of a way to think beyond classically, or beyond the above notion of pen-and-paper maths.

Or are you saying some abstract high-dimensional vector really does ontologically exist in some even higher dimensional space? What space? Not spacetime, that is 4D. And even then how do we reduce that spread out WF to definite values in your ontology.

Math is not an ontology, unless you want to go the Mathematical Universe route.

The refusal of the majority of QM theoreticians to accept MWI is the root cause of the "mystery".

I'm sure decades after Copernicus, there were still astronomers going on and on about the complex interplay of the wanderers, and how the retrograde motion could only be explained with circles up circles, and spheres upon spheres.

This is no different.

I think it's unfair to criticize too harshly those who aren't ready to dive in with MWI. It's not that incomprehensible or too crazy, but it is far beyond what current physics says exists. We'd go from spacetime to some infinite or extremely high-dimensional space. Why should we need to go that far when other interpretations maybe ask less of us.

https://cloudflare-ipfs.com/ipfs/bafykbzacebhd6s3rewniz2q6b3...

pp. 21-35 307-355 355-368 (and more) if you or anyone wants some critiques of MWI

It's so much simpler to model the wanderers as moving along the surface of a celestial sphere! Adding depth adds nothing to our understanding when the current mathematical models can already predict their motion to high accuracy. It's all isomorphic anyway.

Look, just go away with your heretical notions, I have calculations to perform!

Quantum mechanics is completely deterministic. But the point from which we are observing it is random. (Not our origin in space, but our origin in possibilities.) The spread of a waveform is deterministic, but it seems random because we can't predict from which outcome our perspective will originate.

That's why the multiverse interpretation is (imo) the simplest way to reason about QM.

Why? Because he asserts that there is no measurement problem, and that the EPR paradox and violations of Bell's Inequality don't exist: They are based on misunderstanding what QM is actually predicting and what QM observers are actually observing. Likewise, there is no wave function collapse, no need for MWI, no hidden variables, etc.

To sum up the physics, badly....

Background: Relativity took as its principles that physics is universal (the universe is isotropic), that there are no fixed reference frames (all measures of speed, and therefore of a few other things, like energy) are relative to the observer making the measurement), and that the speed of light is a fixed constant. From that we space-time curvature, etc.

Relational QM takes this same perspective: Measurement is relative to the measurer, which can mean an observer or anything else affected by whatever is manifesting itself, like another particle, e.g.

Manifesting is a deliberate word: Absent manifestation, nothing has properties. Properties only make sense in the context of interactions.

What is the charge or spin of an isolated electron? 無 (mu): the question makes no sense, because charge and spin and everything else only arise, are only measurable, in interactions.

So take EPR: There is no paradox, because when Alice measures the spin of one of the entangled particles, she may "know" that Bob will measure or will have measured opposite spin, but she doesn't "know" this yet unless and until she interacted with Bob.

It is only after this slower-than-light communication that the two opposite spins - and the predictions of QM - are confirmed.

Until A and B interacted, entangling their states, the states A-observes-S1 and B-observes-S2 were independent. The interaction between A and B, state "A+B share information re S1+S2", took place without anything ever being FTL, without violations of locality, etc.

What I do not yet know, and have not had enough to look into, is whether and how Relational QM might or does change what we expect of quantum computing. At some point, I'll seek out some Aaronson on the subject, e.g.

Read the book, well worth it.

With a follow-up blog post focusing on entanglement: https://ahelwer.ca/post/2018-12-07-chsh/

There's also this video which walks through how quantum computers solve a very specific factoring problem (Shor's Algorithm) in a way that classical computers cannot. https://www.youtube.com/watch?v=lvTqbM5Dq4Q