Art Hobson

At bottom, Hobson insists, the universe consists not of particles but of fields, the excitations of which are spatially extended (wavy) quanta. For him, this is *the* ontology by which a conservative interpretation of quantum theory (Copenhagen-like but thoroughly and unambiguously psi-ontic) can explain superposition, interference, nonlocality, entanglement, and wavefunction collapse without contradictions. (He likens psi-epistemic views to subjective idealism.) On the measurement problem, he argues that the definite-outcomes aspect is resolved by thinking about "local states" in the right way (e.g.. Schrõdinger's cat presents no paradox since "the measurement state is a [nonlocal and entangled] superposition only of correlations between the nucleus and the cat, not a superposition of the nucleus or of the cat" (p 214)), and that the irreversibility aspect is explained by decoherence theory. Despite far too many instances of "its" being misspelled as "it's", the writing is very crisp and clear. A fine, meaty book.… (mehr)