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Are the Mysteries of Quantum Mechanics Beginning To Dissolve?

Columnist Philip Ball thinks the phenomenon of decoherence might finally bridge the quantum-classical divide.

Are the Mysteries of Quantum Mechanics Beginning To Dissolve? | Quanta Magazine

Columnist Philip Ball thinks the phenomenon of decoherence might finally bridge the quantum-classical divide.

Quanta Magazine
Mar 2 at 1:58amWeb
Show threadsolrizeMar 2
Quanta is sure publishing some crappy clickbait these days. A couple days ago the weird piece about Georg Cantor, and now this. Yes decoherence is one of many possible explanations of quantum measurement. No it doesn’t settle the issue.
Show threadUNY0NMar 2

This guy must be on to something. Look at that hair! That is some Einstein-level-crazy-genius hair.

Seriously though, I applaud the return to systematic and grounded theory, and enjoyed the article. The title is a little too click-baity, but the content is factual and sober imho.

Show threadsolrizeMar 2
Show threadbunchberryMar 3

There is no mystery. Realism requires object permanence, and object permanence requires that you believe in counterfactual statements. If I measure something at t=0 and t=2, I could have measured it at t=1, and so you have to believe it had a value at t=1 or else you devolve into solipsism. If you believe an objective reality exists at all then you have to uphold these kinds of counterfactuals or else you have no basis to believe that objective reality exists independently of you measuring or observing it.

Bell’s proves clearly proves that special relativity simply lacks sufficient structure needed to give a realist account of the world. Special relativity is not compatible with objective reality. Rather than accepting this conclusion and admitting special relativity needs additional structure added to it, physicists almost universally came to the consensus that we should reject the very idea that there exists an objective reality independent of observation to preserve the sacred status of special relativity

This became the dominant Copenhagen interpretation. Physics is just about what shows up in measuring devices, during observation, not about objective reality. Many Worlds then showed up later as a cope. It arose as a middle-ground by arguing the mathematics used to predict what shows up on measuring devices is objective reality, as if we live in a Platonic realm of mathematics given by the idealized qmstate vector in infinite dimensional Hilbert space.

This coping mechanism is not even coherent. You can’t derive an “ought” statement from a lot of “is” statements. The conclusion can never be stronger than the premises. Similarly, you cannot derive observability by starting from pure mathematics where nothing is observable. Many Worlds has no algebra of observables and it is logically impossible to derive them. You must begin with objects defines in terms of their observables and fit models to their dynamics. You cannot logically start from the Platonic realm of our mathematics.

It is just a coping mechanism to avoid questioning the completeness of special relativity while also saying you don’t deny objective reality by turning the pure mathematics into objective reality.