In an unpublished 1933 paper, Grete Hermann noted an error in this physicist’s proof of the impossibility of hidden variables. For 10 points each:
[10h] Name this physicist who formalized quantum mechanics using functional analysis in the book Mathematical Foundations of Quantum Theory. This physicist names a type of C-star algebra that is closed under the weak operator topology.
ANSWER: John von Neumann (“NOY-mahn”) [accept von Neumann algebra]
[10m] The crux of Hermann’s critique is that von Neumann defines this operation, which equals bra-psi A ket-psi for an observable A, to be linear even for non-commutative observables. This operation is denoted with angle brackets around a symbol.
ANSWER: expectation value [or expected value; prompt on mean or average; prompt on EV or E]
[10e] Von Neumann’s assumption was later criticized by John Stewart Bell, whose inequality is violated by pairs of particles with this property. The states of two particles with this property cannot be described independently.
ANSWER: quantum entanglement [or word forms like entangled]
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