In this paper we investigate the history of relationalism and its present use in some interpretations of quantum mechanics. In the first part of this article we will provide a conceptual analysis of the relation between substantivalism, relationalism and relativism in the history of both physics and philosophy. In the second part, we will address some relational interpretations of quantum mechanics, namely, Bohr's relational approach, the modal interpretation by Kochen, the perspectival modal version by Bene and Dieks and the relational interpretation by Rovelli. We will argue that all these interpretations ground their understanding of relations in epistemological terms. By taking into account the analysis on the first part of our work, we intend to highlight the fact that there is a different possibility for understanding quantum mechanics in relational terms which has not been yet considered within the foundational literature. This possibility is to consider relations in (non-relativist) ontological terms. We will argue that such an understanding might be capable of providing a novel approach to the problem of representing what quantum mechanics is really talking about.
In this paper we investigate the history of relationalism and its present use in some interpretations of quantum mechanics. In the first part of this article we will provide a conceptual analysis of the relation between substantivalism, relationalism and relativism in the history of both physics and philosophy. In the second part, we will address some relational interpretations of quantum mechanics, namely, Bohr's relational approach, the modal interpretation by Kochen, the perspectival modal version by Bene and Dieks and the relational interpretation by Rovelli. We will argue that all these interpretations ground their understanding of relations in epistemological terms. By taking into account the analysis on the first part of our work, we intend to highlight the fact that there is a different possibility for understanding quantum mechanics in relational terms which has not been yet considered within the foundational literature. This possibility is to consider relations in (non-relativist) ontological terms. We will argue that such an understanding might be capable of providing a novel approach to the problem of representing what quantum mechanics is really talking about.
Recent no-go theorems challenging the absoluteness of events have highlighted the possibility that dynamical facts in quantum theory are observer-relative. This thesis examines the metaphysical and conceptual foundations of quantum relativism, focusing on Relational Quantum Mechanics (RQM). It analyzes arguments for relativism through Wigner’s Friend and Extended Wigner’s Friend thought experiments, explores the link between relative physical facts and experiences, and offers the first metaphysical definition of "relative facts." The thesis argues: RQM supports a perspectival retro-determination of past events based on later acquisition of information; Quantum relativists must also relativize facts about observers’ experiences; the strongest arguments for relativism lead to unbounded higher-order relativity, precluding any absolute 'view from nowhere'; Only a metaphysical framework that relativized the composition of reality itself can accommodate such an unrestricted iteration. These conclusions deepen our grasp of a thoroughly perspectival quantum world.
In correspondence with the modal interpretations of quantum mechanics, Lombardi and Castagnino (2008) and da Costa, Lombardi and Lastiri (2013) have proposed an ontology of bundles of possible intrinsic properties for quantum mechanics, focused mainly on the issues of quantum contextuality and indistinguishability. Corresponding to the interpretation known as "relational quantum mechanics" (Rovelli, 1996), two ontologies based on relations have been proposed. Laura Candiotto (2017) advocates for a radical metaphysics of relations, considered by the author as an instance of the so-called "ontic structural realism". Alternatively, Andrea Oldofredi (2021) proposes an ontology of bundles of relations, considered by the author as an instance of the so-called "moderate structural realism". Since the 1980s, the topic of quantum entanglement has led several authors (Teller, Healey, Howard, Esfeld) to defend that quantum mechanics involves a form of holism. It has been argued that the holism of quantum mechanics supports the metaphysical thesis known as "priority monism" (Schaffer, 2010a). In this article, an ontology of quantum mechanics is proposed in which the properties of quantum systems have both a modal and a relational character. As a result, a holistic ontology of quantum mechanics is obtained, which is an instance of priority monism and moderate structural realism.
Abstract The following paper explores the metaphysical significance of Relational Quantum Mechanics (RQM). For this, I will first outline Rovelli’s philosophical framework, and then offer a reconstruction of Rovelli’s seminal argument in favour of RQM. I will then explore some healthy lines of philosophical work that may be undertaken to strengthen RQM. First, I will frame RQM in the debate between realist and antirealist readings of QM and defend the general claim that RQM is compatible with realism. Then, I discuss the main ontological interpretations of RQM, which I classify as “dispositional”, “transcendental” and “structural”, and argue that all of them remain committed to substantialist assumptions that limit the radicality of Rovelli’s proposal. Finally, I analyse recent developments on RQM’s ontology and suggest that preserving its ontological originality requires an assessment on the concept of “pattern”.
Niels Bohr, considered one of the fathers of quantum mechanics, formulated a complex interpretation \nof quantum mechanics that guided his understanding of quantum experiments. The contemporary dispute \nbetween realism and anti-realism, the two main approaches to the interpretation of quantum mechanics, \nis often based on different attitudes towards or even readings of Bohr. We propose that a better \nunderstanding of Bohr’s philosophical thought can contribute to the contemporary reconciliation of \nthese opposing philosophical views and thus to a better understanding of the quantum world. Unfortunately, \nin many contemporary interpretations, Bohr’s philosophical approach to quantum mechanics \nhas been misunderstood, re-interpreted or labelled as ambiguous. This is mostly due to the dispersion \nof Bohr’s complex and unique interpretation through different texts, never united in a single systematically \nconceptualized work. To comprehensively explain Bohr’s philosophical approach and his main \nphilosophical concepts, we consider the many similarities between Bohr’s and Husserl’s philosophical \napproach to science. Husserl developed his philosophical standpoint in a cultural context similar to \nBohr’s and shared Bohr’s objects of philosophical consideration as well as his approach to these objects. \nParallel reading of Bohr’s and Husserl’s texts reveals the closeness between Bohr’s ontological realism— \nepistemological anti-realism standpoint and Husserl’s phenomenological standpoint. This explains \ntheir similar views on the relationship between mathematical language, scientific method and Nature. \nWhile Bohr’s use of the term phenomenon is not equal to Husserl’s, Husserl’s rigorous philosophical \nexplanation of the term helps us to better understand Bohr’s use. Furthermore, the parallel reading \nfacilitates better understanding of one of Bohr’s main philosophical theses, often labelled as ambiguous \nand interpreted in different ways, that it is necessary to use classical concepts to describe quantum phenomena. \nWe claim that the thesis is connected with the advance of epistemological reconsideration of \nscience at the time of Bohr’s writing. Thus, Bohr considers some parts of argumentation as self-evident, \nwhile they are not evident to the contemporary reader. Husserl’s analysis of the relationship between science and the life-world offers a much-needed background for a comprehensive understanding of \nBohr’s thesis. The insight into the similarities between Bohr’s and Husserl’s philosophical approach \nto science and scientific phenomena enables a philosophically rigorous reading of Bohr’s texts; it can \neliminate some of the disagreements between realists and anti-realists and provide a firmer philosophical \nground for a dialog between them.
Relational Quantum Mechanics (RQM) is an interpretation of quantum theory based on the idea of abolishing the notion of absolute states of systems, in favor of states of systems relative to other systems. Such a move is claimed to solve the conceptual problems of standard quantum mechanics. Moreover, RQM has been argued to account for all quantum correlations without invoking non-local effects and, in spite of embracing a fully relational stance, to successfully explain how different observers exchange information. In this work, we carry out a thorough assessment of RQM and its purported achievements. We find that it fails to address the conceptual problems of standard quantum mechanics--related to the lack of clarity in its ontology and the rules that govern its behavior--and that it leads to serious conceptual problems of its own. We also uncover as unwarranted the claims that RQM can correctly explain information exchange among observers, and that it accommodates all quantum correlations without invoking non-local influences. We conclude that RQM is unsuccessful in its attempt to provide a satisfactory understanding of the quantum world.
This article offers a critical analysis of Carlo Rovelli’s conceptual positions in works devoted to interpretations of quantum mechanics and the notion of time. Attention is paid to the relational interpretation developed by the author in “Helgoland: Making Sense of the Quantum Revolution” and to its philosophical foundations, which go back to the ideas of Ernst Mach and Nagarjuna. The article examines key elements of the quantum-mechanical formalism, including the superposition principle, interference effects, and commutation relations, with emphasis on their interpretive consequences. The article also analyzes Rovelli’s critical remarks on alternative approaches, such as Hugh Everett III’s many-worlds interpretation, hidden-variable theories associated with the works of Louis de Broglie and David Bohm, as well as models that propose a physical explanation of wave-function collapse. It is shown that some of the author’s arguments are limited in scope and do not consider contemporary experimental results, in particular studies that cast doubt on the epistemological interpretation of the wave function. Special attention is given to internal contradictions in Rovelli’s relational approach, including the problem of the ontological status of objects and the reconciliation of the principle of relationality with the existence of invariant physical quantities. The interpretation of time given by Rovelli in works such as The Order of Time and A Brief History of Time is also examined. The limitations of his ontological approach to time within loop quantum gravity are emphasized.