We discuss several problems that arise in the Copenhagen interpretation of quantum mechanics, in an attempt to come to grips with what E. T. Jaynes has called the quantum omelette.1
In this paper we discuss the so called "quantum omelette" created by Bohr and Heisenberg through the mix of (ontic) objective accounts and (epistemic) subjective ones within the analysis of Quantum Mechanics (QM). We will begin by addressing the difficult relation between ontology and epistemology within the history of both physics and philosophy. We will then argue that the present "quantum omelette" is being presently cooked in two opposite directions: the first scrambling ontological problems with epistemological solutions and the second scrambling epistemic approaches with ontological questions. A good example of the former is a new type of argumentation strategy attempting to justify the use of decoherence, namely, the "For All Practical Purposes" (shortly known as FAPP) type of justification. We will argue that 'FAPP-type solutions' remain, at best, epistemological answers which not only escape the ontological questions at stake -regarding the quantum to classical limit- but also turn the original problem completely meaningless. The latter omelette can be witnessed in relation to some criticisms raised against the epistemic Bayesian approach to QM (shortly known as QBism). We will argue that QBists have produced a consistent scheme that might allow us to begin to unscramble -at least part of- the "quantum omelette". In this respect, we will show why the epistemic QBist approach is safe from several (ontological) criticisms it has recently received (see [42, 47, 48]). We end our paper with a discussion about the importance of ontological approaches within foundations of QM.
Abstract This chapter explores a serious epistemic problem for the class of ‘orthodox interpretations’ (including QBism, neo-Copenhagen interpretations, pragmatic interpretations and some versions of relational quantum mechanics) and discusses various possible attempts at a solution. I contend that the difficulty of making sense of intersubjectivity in orthodox interpretations makes these approaches self-undermining. I argue that these approaches forbid observers from sharing information with one another or even past versions of themselves, and explain why information-sharing is an essential feature of scientific practice and scientific epistemology. I also discuss some ‘Extended Wigner’s Friend’ theorems which have recently attracted interest in quantum foundations, arguing that we must interpret these theorems in light of the social dimensions of scientific knowledge.
In this paper we attempt to analyze the physical and philosophical meaning of quantum contextuality. In the first part we will argue that a general confusion within the literature comes from the improper "scrambling" of two different meanings of quantum contextuality. The first one is related to an epistemic interpretation of contextuality, introduced by Bohr, which stresses the incompatibility (or complementarity) of quantum measurements. The second, is related to an ontic notion of contextuality, exposed through the Kochen-Specker (KS) theorem, which focuses on the constraints to discuss about actual (definite valued) properties within the orthodox formalism of QM. We will show how these two notions have been scrambled together creating an "omelette of contextuality" which has been fully widespread through a popularized "epistemic explanation" of the KS theorem according to which: The outcome of the observable A when mea- sured together with B or together with C will necessarily differ in case [A,B] = [A,C] = 0, and [B,C] ̸= 0. We will show why this statement is not only improperly scrambling epistemic and ontic perspectives, but is also physically and philosophically meaningless. In the second part of the paper, we will analyse the relation between ‘classical contexts’ and QM. We will show that three accepted presuppositions found within the orthodox literature are, in general, false. Namely: (i) that quantum contextuality does not preclude an objective description of physical reality, (ii) that the choice of a context (or basis) restores a classical description of reality, and (iii) that the choice of a (classical) context is a necessary condition for accounting for empirical statements in QM.