Article “QBism”: The most radical interpretation of quantum mechanics ever

[C C]

https://bigthink.com/13-8/qbism-quantum-physics/

A relatively new interpretation of quantum mechanics asks us to reimagine the process of science itself.

KEY POINTS: Quantum mechanics, despite being the most powerful theory in physics, presents a complex picture that often defies common sense and is riddled with paradoxes. "QBism," or "Quantum Bayesianism," offers a radical interpretation of quantum physics, suggesting that quantum states are not objective realities. Instead, the interpretation posits that quantum states reflect our subjective understanding and interactions with the quantum world.

EXCERPT: ... QBism takes an entirely different stance. It looks at the changes that the inventors of quantum mechanics were forced to make and draws a truly radical but also radically level-headed conclusion: The quantum state, with its simultaneous superposed possibilities, is not something that exists out there by itself. A state is not something a particle “has” as a property, like the way a house has the property of being painted blue. Instead, quantum states are about our knowledge of the world. They are descriptions encoding our interactions with particles.

QBism would say it’s not the particle’s state — it’s your state about the particle. QBism leads not with ontology — a story about what fundamentally exists independent of us — but with epistemology: a story about our information about the world. That change makes all the difference. By refusing to force an old philosophy that came prepackaged with classical physics to be retained no matter what the cost, QBism doesn’t have to force us to accept science-fiction stories about parallel realities (or other such unobservable “entities”) into science. Instead, QBism leads with experience. What, it asks, actually happens when human beings do quantum physics?

The answer QBism produces is as radical as it is mundane. By turning away from an impossible (and paradoxical) God’s-eye view of the Universe, QBism puts human beings squarely in the middle of the scientific enterprise. In this way, I believe, it “gets” what quantum mechanics has been trying to tell us since its invention a century ago.

To do physics is not to gain some mythical and supreme perspective but to watch as subjects (people like you and me) gain knowledge about the world. What’s more, and what’s more exciting than that mythical supreme view, is that really understanding quantum mechanics means understanding how we and the world are always woven together as an inextricable whole. Unpacking that perspective is what’s at the heart of QBism’s ambitious research program, and it’s what we’ll be unpacking as this series progresses... (MORE - missing details)

[Magical Realist]

To do physics is not to gain some mythical and supreme perspective but to watch as subjects (people like you and me) gain knowledge about the world. What’s more, and what’s more exciting than that mythical supreme view, is that really understanding quantum mechanics means understanding how we and the world are always woven together as an inextricable whole.

Thru the physicality of our bodies and brains, we participate in the objective being of the world. But thru the mentality of our minds, we also participate in the non-local nature of reality. We are both here and now as well as nowhere at once. A fusion of facticity and transcendence. We are participants in this paradoxical state of being and nonbeing. What we observe is both perceived locally and conceived universally. Everything is thus fundamentally connected and interactive, at once empirical and rational, including us.

[confused2]

Probably unhelpful to point out that quantum mechanics worked perfectly well for billions of years before there were any humans around to imagine they played any part in the way quantum mechanics actually works.

[C C]

However, things are very different in quantum mechanics. Quantum states can be “superposed,” meaning a particle can have many values of position and momentum at the same time (like a coffee cup being in many places at one time)...

[...] Many quantum interpretations have recoiled in horror from this situation. Their goal is to try to preserve the classical view where physics equations are kind of like “the thoughts in God’s mind.” These interpretations take an ontological view of the quantum state, including its superpositions. The quantum state is really real. It is “out there,” as a real thing in the real world, independent of us. But given the superpositions, there is a price to pay for this kind of ontological commitment ... such as parallel universes splitting off every time a quantum measurement is made. Parallel universes sound cool for science-fiction movies, but really they’re an extravagant price to pay for holding on to the metaphysical preferences of classical physics.

Quantum computers actually work, however. They couldn't produce their results without the superpositional description of sufficiently tiny-sized things corresponding to a real or non-symbolic state of affairs. (Similarly, there are technologies dependent on quantum tunneling, entanglement, etc.) That doesn't necessarily mean "many worlds" is the case, but it reifies something "extraordinary" for at least an extended duration that upholders of quantum idealism don't want or themselves "recoil in horror" from.

Radical empiricism, scientific anti-realism, etc can get around that by declaring that the sensible world (particularly with respect to instruments and technology) merely behaves as if such abstractions represent real existential or ontological items/conditions. Just as they would espouse (with respect to GR) that the results of applicable experiments merely conform to the idea of spacetime in a regulatory way, as if the latter were real.

But that's so close to the curving into the hole of "we're in a simulation" hypothesis (or something equivalent) that it's hardly worth all the complicated efforts and denials expended over the next 1,000 years to keep from rolling into it. Whatever underlying substrate implements a simulation wouldn't want to expend absurdly extravagant resources maintaining certain levels of its generated reality that don't even matter except when observed by denizens with cognition, or when such is inferred from the effects of those normally "invisible" domains.