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I only skimmed this article, but I didn't like very much what I read. It glosses over some very real philosophical problems associated with QM, and pretends they're not problems.

(N.B.: When I say "problems", I don't mean mathematical inconsistencies in the theory or disagreements between the theory and experimental fact--we know of none--but rather refutations of our naive philosophical expectations.)

For example, with Schrödinger's Cat, he shrugs and says, "QM can't predict the future, no problem". But the problem isn't a question of the future; it's a question of the past.

Suppose the decision whether to release the prussic acid occurs at 4:00, and the chamber is opened at 5:00. The cat is in a superposed dead/alive state at 4:30. It will collapse at 5:00 into one state or the other, sure, but that doesn't mean the cat will live or die at 5:00. The death of the cat, if death is the outcome, will have occurred at 4:00. At 4:30, that event is already in the past. At 5:00, when the mixed state collapses into the death eigenstate, the cat will be an hour dead. It's not the future which is indeterminate, but the past.

Furthermore, the author misleads when he says "we never see this". We may not see it with cats in our sadistic basement experiments, but we see it in the lab, with subatomic particles. Indeed, we exploit it as an experimental tool.

It's possible that Quincey might respond by elaborating on these sentences:

But if quantum mechanics can accurately describe all the information we can ever obtain about the outside world, perhaps we are simply being greedy to ask for anything more. The headline "Physics Fails to Describe Events That Cannot Be Observed" is, again, rather lacking in impact.

Puzzles about superposition strike me as being modern instantiations of the problem of the one and the many. If I had more time (and were much, much smarter), I'd say more.

For example, with Schrödinger's Cat, he shrugs and says, "QM can't predict the future, no problem". But the problem isn't a question of the future; it's a question of the past.

In the Copenhagen Interpretation, QM only represents our state of knowledge of a system. With the cat hidden in the box, QM only predicts the probability of what we will find when we open it.

Suppose we put a clock in the box instead of a cat, rigged to stop when the quantum event is detected. When we open the box we will find it running or stopped, and in the latter case we may certainly say that the time it records is the time of the quantum event.

Note that even a dead cat is an evolving system, and we may say by various means such as temperature when it died, even if we weren't watching. The cat is no different than a clock in this way.

This famous paradigm is more a rhetorical exercise than philosophical. The characterizations of "dead" and "alive" as quantum states is entirely unjustified, but the drama of the situation distracts us from noticing.

Suppose the decision whether to release the prussic acid occurs at 4:00, and the chamber is opened at 5:00. The cat is in a superposed dead/alive state at 4:30. It will collapse at 5:00 into one state or the other, sure, but that doesn't mean the cat will live or die at 5:00. The death of the cat, if death is the outcome, will have occurred at 4:00. At 4:30, that event is already in the past. At 5:00, when the mixed state collapses into the death eigenstate, the cat will be an hour dead. It's not the future which is indeterminate, but the past.

Fascinating. For a layman, I would love to be able to read something that will delve further into this. Got any specific links?

I think the intention of the author was not necessarily to gloss over the philosophical problems associated with QM, but to dispel of the notion that it somehow means that we can't understand what it leads to, as well as the mystical New Age hippie crap that some people try to justify with an appeal to QM (note the article source). People think that wave-particle duality or non-locality is something mysterious, implying that reality is subjective and malleable; it doesn't. They're very real outcomes of physical laws predicted by quantum mechanics (and in the case of wave-particle duality, special relativity as well). The problem, to paraphrase The Bard lies not in the universe, but in our minds, as our cognitive abilities and reasoning skills are specifically adapted to the non-quantum world (there, I've hijacked this, and made it a crevo thread!). Just as our telescopes and microscopes, optical, radio and electron, are helping us go beyond the sensory impressions which limit us thank to natural selection, so will the next wave of advances in computation help us go beyond our limited cognitive faculties, evolved to respond specifically to casual reasoning.

"It's not the future which is indeterminate, but the past." Actually, could we say that to a finite living observer that may be so, but the universe has no problem with the deterministic state of past, because it (the event as present when it happened) is entangled with the origin of the universe itself? To imply that the cat died at 4 but is in superposition until an observer notes the cat, is a false assertion (else nothing would have 'finished' prior to living observers being in the universe; everything would have been in superposition from the big bang onward, until living observers arrived, somehow). The universe is 'an' observer (because past and present exist in simultaneity in which the event of death occurred) but superposition is a temporal problem for the finite living observer due to the nature of the observers fix in time as always in 'planar' present while alive, yet sensing ONLY events that have already occurred. I like, for thought purposes, to think of past as linear and the ends of each pathway form the plane of present, with the 'blossom' of future the 'every path possible from present' on the opposite side of the planar present from the linear past.