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No, I'm saying that you can't solve the "measurement problem" by considering only closed quantum systems. This is the one thing where Bohr was right: Measuring a quantum system means to use a macroscopic apparatus to gain information about this quantum system, and a measurement implies an irreversible process letting me read off a pointer at that instrument. This you cannot describe by a closed system (neither in classical mechanics or field theory nor in quantum (field) theory).
In classical as well as quantum physics you derive the behavior of macroscopic systems by a plethora of methods leading to an effective description leading to irreversibility, dissipation and particularly, in the quantum case, decoherence.
What is empty philosophy is to claim you can describe macroscopic systems in all microscopic detail as closed quantum systems. It's also empty philosophy to claim that there's a measurement problem only because of this impossibility. If you wish it's the same empty philosophy as to claim that there is a problem, because we are able to describe nature with mathematical models at all. It's just an observed fact that we can to an amazing extent, as it is an observed fact that we are able for the last 400+x years to invent better and better instruments to measure and thus quantify with higher and higher accuracy all kinds of phenomena, and this is enabled by both these experimental and engineering achievements and its interplay with theory, which enables us to think and talk about phenomena that exceed or direct abilities by several orders of magnitude in scales (from the microscopic subatomic/subnuclear dimensions below 1 fm up to very large astronomical if not even cosmological scales). It's empty philosophy (though pretty entertaining sometimes) to ask, why this quantitative description of our universe is possible at all.
In classical as well as quantum physics you derive the behavior of macroscopic systems by a plethora of methods leading to an effective description leading to irreversibility, dissipation and particularly, in the quantum case, decoherence.
What is empty philosophy is to claim you can describe macroscopic systems in all microscopic detail as closed quantum systems. It's also empty philosophy to claim that there's a measurement problem only because of this impossibility. If you wish it's the same empty philosophy as to claim that there is a problem, because we are able to describe nature with mathematical models at all. It's just an observed fact that we can to an amazing extent, as it is an observed fact that we are able for the last 400+x years to invent better and better instruments to measure and thus quantify with higher and higher accuracy all kinds of phenomena, and this is enabled by both these experimental and engineering achievements and its interplay with theory, which enables us to think and talk about phenomena that exceed or direct abilities by several orders of magnitude in scales (from the microscopic subatomic/subnuclear dimensions below 1 fm up to very large astronomical if not even cosmological scales). It's empty philosophy (though pretty entertaining sometimes) to ask, why this quantitative description of our universe is possible at all.