A Principle Response from Quantum Information Theorists

Abstract

Abstract Chapter 6 explains the axiomatic reconstruction of quantum mechanics via information-theoretic principles. Hardy’s reconstruction is featured because it shows that the quantum probability theory of quantum mechanics obtains by adding the word “continuous” to the fifth axiom of classical probability theory. As explained in Chapter 0, continuity is responsible for superposition, so the quantum bit (qubit) differs from the classical bit because the states of a qubit are superpositions. The Planck postulate is shown to follow from Brukner and Zeilinger’s principle of Information Invariance & Continuity at the foundation of their reconstruction, so quantum mechanics can be understood as a principle theory based on NPRF + h. We show that ‘average-only’ projection is one way to characterize the ‘weirdness’ of the qubit. Grinbaum’s reconstruction based on relational quantum mechanics is introduced.