The Contextuality of Quantum Theory in Ten Minutes

Through my computer science “information is king” eyeglasses, there are really only two notions which thoroughly distinguish quantum theory from classical theories of how the world works: the nonlocal nature of quantum correlations as exemplified by Bell’s theorem and the much less well known contextual nature of quantum measurements as exemplified by the Bell-Kochen-Specker theorem. While the former is well known (and hence, to paraphrase Gell-Mann, what you’ve heard about it is mostly wrong), the later is less well known. Is that because it is a complicated idea? I don’t think so! Indeed I think you can learn what quantum contextuality means in less than ten minutes. Yep, it’s another edition of “explain quantum theory in ten minutes!”
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Merry Quantum Christmas!

Merry Christmas! I don’t think this explanation for Santa delivering presents using quantum theory works. But it does bring up the question of whether Santa could get a quadratric speedup using quantum gift delivery?