Relational Interpretations

Planck's constant h and Boltzmann's constant kB conventionally connect spectral frequency to energy and energy to temperature. Recent analysis of blackbody spectral relations in the frequency domain revealed an unexpected result. Unlike conventional physical constants, which typically appear in the slopes of individual relations as local scaling factors, the ratio h/kB does not appear in any individual relation. Instead, different relations between spectral observables and temperature fail to close, and h/kB emerges as the intercept residual of that non-closure. This suggests (...) that h/kB acts as a global consistency factor required to reconcile the different mappings. This observation raises a deeper question. If h/kB appears neither in the spectral observables nor in temperature itself, but only in the mapping between them, is it describing the empirical structure being observed, or the mapping used to represent it? More generally, are physical constants merely scaling factors between equivalent domains of description, or do they connect fundamentally different domains? We explore this question by distinguishing between an empirical domain of directly measurable spectral quantities such as frequency, phase, and linewidth, and a representational domain of abstract constructs used to represent those observations, including temperature, energy, entropy, and spatial parametrizations. Within this framework, physical constants are interpreted as quantities introduced to achieve internal consistency among different representations of the same empirical structure. We develop this perspective through the concept of Domain Projection and discuss its implications for the interpretation of physical constants, physical laws, and the foundations of scientific description. (shrink)

Modern science relies on representational models that organize empirical observations through constructs such as electrons, energy levels, spacetime, wavefunction and causal mechanisms. While these models achieved extraordinary predictive success, they also led to an implicit inversion in which these unobservable theoretical constructs are treated as explanatory ground and observable spectral regularities as derivative. Recent large-scale analyses of atomic spectra reveal that diverse physical measurements exhibit unexpectedly low-dimensional and relational organization recoverable directly through frequency-domain relations, without introducing hidden entities or theoretical (...) assumptions. These results show that classification, compression, generalization, and prediction emerge naturally from intrinsic spectral structure prior to representational interpretation. The paper argues that representation reorganizes empirical structure rather than generates it and becomes methodologically secondary once observable relations exhibit predictive closure. The persistent demand for additional mechanistic explanation arises not from deficiencies in empirical structure, but from the expectation that physical understanding must ultimately be translated into narratives of localized objects, linear causality, and particle interactions. Once representational constructs acquire explanatory authority beyond their empirical origin, they tend to stabilize and reify, expanding the theoretical apparatus to accommodate inconsistencies. This motivates the concept of representational debt, whereby additional abstract layers accumulate beyond empirical necessity, increasing descriptive complexity and delaying the discovery of simpler organizing principles. More broadly, the analysis motivates Foundational Science, a discipline concerned not with ontological entities or local causal mechanisms, but with invariant relations, scaling laws, and structural constraints. The Spectral Framework is presented as an empirical realization of this methodological perspective, illustrating how scientific explanation may be re-grounded in simple organizational principles already present in measurements. (shrink)

The quantum measurement problem, particularly the observer effect, has long resisted a complete explanation, often forcing a choice between paradoxical interpretations and a fundamental split between the quantum and classical worlds. This paper introduces Aethic reasoning, a novel framework that resolves the measurement problem by reformulating the logical and relational structure that underpins reality. We propose three foundational postulates that redefine realism, superposition, and state validity from a relational standpoint. The derivation begins with the Third Postulate, which posits that reality (...) is governed by a logical “checkmate” rule that invalidates any state where, in every possible future, a path to a contradiction persists. We demonstrate how this single constraint—a universe that tirelessly avoids paradox—logically necessitates the relational framework of the First Postulate, where realism is defined relative to an observer's informational state, or Aethus. Building on this, the Second Postulate, in conjunction with the Extrusion and Union Principles, provides a mechanism for defining superposition as a direct consequence of unknowable information. Together, these postulates form a cohesive system that yields a direct, step-by-step derivation of the double-slit experiment's outcomes. Aethic reasoning thus offers a robust and logically consistent solution to the quantum observer effect, unifying quantum and classical phenomena without introducing new physical entities or paradoxes. (shrink)

The quantum measurement problem is one of the most profound challenges in modern physics, questioning how and why the wavefunction collapses during measurement to produce a single observable outcome. In this paper, we propose a novel solution through a logical framework called Aethic reasoning, which reinterprets the ontology of time and information in quantum mechanics. Central to this approach is the Aethic principle of extrusion, which models wavefunction collapse as progression along a Markov chain of block universes, effectively decoupling the (...) Einsteinian flow of time from quantum collapse events. This principle introduces an additional degree of freedom to time, enabling the first Aethic postulate: that informational reality is reference-dependent, akin to the relativity of simultaneity in special relativity. This reference point, or Aethus, is rigorously defined within a mathematical structure. Building on this foundation, the second postulate resolves the distinction between quantum superpositions and logical contradictions by encoding superpositions in a “backend” Aethic framework before rendering observable states. The third postulate further distinguishes quantum coherence from decoherence using a two-generational model of state inheritance, potentially advancing beyond simpler interpretations of information leakage. Together, these postulates yield a direct theoretical derivation of the collapse postulate, fully consistent with empirical results such as the outcome of the double-slit experiment. By addressing foundational aspects of quantum mechanics through a logically robust and philosophically grounded lens, this framework sheds new light on the measurement problem and offers a solid foundation for future exploration. (shrink)

This article develops a metatheoretical claim about a specific class of intellectual operations in foundational physics. It distinguishes between solving an interpretive problem in its own terms, replacing the theory that generated the problem, and dissolving the problem by displacing the ontological presupposition that gave it its shape. The third operation, which the article calls ontological reframing, is defended as a legitimate kind of contribution to foundational debate and exhibited at length on the double-slit experiment and the measurement problem. The (...) article does not propose a new physical theory, a new mathematical formalism, or a new interpretation of quantum mechanics in the standard sense. It argues instead that the canonical puzzle rests on an ontological presupposition that the formalism itself does not require: that a physical object exists in the real domain, travels from source to detector, and is then measured. The formalism requires state assignment, preparation, unitary evolution, and measurement; it does not by itself require the substance-like reading of the state as a continuously existing object in the real domain. In the OTS reading, before measurement there is no real-domain particle in transit. There is an idempotent configuration in the dual domain: the source, as a real-domain device, fixes the structural conditions of that configuration; the apparatus determines the admissible modes of its valence; and the detector induces the only irreversible passage from dual to real. The click, trace, or mark on the screen is therefore not the final position of a travelling particle, but the first real-domain event of the quantum entity. The article situates the move within Transformative Semalgebraic Ontology (OTS), but treats that framework as data rather than as something to be defended. What is defended here is the operation itself: a metatheoretical change of philosophical environment in which some questions cease to ask for closure. (shrink)

Quantum mechanics and the metaphysics of consciousness are usually pursued apart; this paper joins them with a result and an interpretation. The result: the number of unified subjects of experience — the cardinality of experience — is not fixed by anything operationally accessible to a localized perspective in a no-collapse setting; we exhibit this computationally and state it precisely. The significance of the result lies less in the underdetermination itself than in what follows from it: the decombination problem (the standard (...) objection to cosmopsychism) and Everett's how-many-minds problem are the same underdetermination seen from opposite sides, meaning the dialectical cost is shared, not a special liability of consciousness-first views. The non-determination isolates the minimal posit every no-collapse interpretation must add. Taking that posit as ground yields a structural cosmopsychism on which a universal subject's self-relational structure is the Hilbert-space structure. Advaita Vedānta supplies illuminating labels for moves the view defines independently. (shrink)

This paper argues that the foundational problems of modern physics arise from a failure to distinguish properly between form and actuality, and from the consequent treatment of objects as metaphysical primitives. It develops a relational framework in which determinacy is not given, but achieved through three irreducible processes of relational ordering: synchronicity, recursion, and return. Synchronicity defines the rest frame as a condition of simultaneous co-presence in which formal spatial relations and actual temporal processes are cleanly distinguished. Recursion generates spatial (...) extension through iterative exchange, while return brings distributed processes into closure as determinate unities. Light is interpreted as the invariant mediator between formal spatial structure and actual temporal unfolding, governing the relation between propagation and completion. Within this framework, the relation E=mc^2 is derived as the identity of external exchange and internal completion under conditions of return, while the Heisenberg relations of indeterminacy are shown to express a single invariant constraint on incomplete cycles. Relativity theory is reinterpreted as a transformation of frames that breaks synchronic symmetry while preserving invariant structure. Crucially, the rest frame is identified as the condition under which physical systems can be formalized as actual for an observer; it is only under this condition that the primitive categories of space and time can be cleanly distinguished, and therefore only under this condition that interpretative processes of actualized determination are possible. The paper concludes that objects are not metaphysical primitives; rather, physical reality consists of relations that become determinate only through their own enactment. (shrink)

A phenomenological exploration of the distinction between a relational formal ontology (also called a process ontology) and a classical formal ontology (also called an object ontology) for modelling physical phenomena that exhibit relationally-mediated holism, such as phenomena from quantum physics and biosemiotics. Whereas a classical formal ontology is based on mathematical objects and classes, a relational formal ontology is based on mathematical signs and categories. A relational formal ontology involves nodal networks that are dynamically sustained through signalling. Nodal networks are (...) systems of constrained iterative processes (dynamical nodes) that have individual semiotic agency within a matrix of determinate possibilities (a semiotic scaffolding). The nodal networks are hierarchically ordered and exhibit characteristics of deep learning. Clarifying the distinction between classical and relational formal ontologies may help to clarify the role of interpretative context in physics (eg. the role of the observer in quantum theory), the role of signalling in biological systems and the role of hierarchical nodal networks in computational simulations of learning in generative artificial intelligence (AI). Two experiments are conducted to explore the application of key principles of relational ontology in AI, namely, complex pattern abduction involving hierarchies of categories and progressive determination through placeholder signs. (shrink)

[With the assistance of Chat GPT] This paper examines large language models (LLMs) through a hierarchical relational and semiotic framework, arguing that standard descriptions of LLMs as session-isolated, parametrically fixed stochastic systems are insufficient to account for how semantic coherence is produced. While model parameters remain unchanged during inference, meaning is enacted through trajectories of activation and calibrated within the coupled human–AI system via shared language rather than stored as internal semantic states. From an engineering perspective, this reframes calibration and (...) coherence as properties of system–environment interaction rather than internal state updates, with implications for evaluation, alignment, and interpretability. Philosophically, the analysis advances a processual, non-representational characterization of ontology in which meaning-producing relations are formally non-separable, challenging state-based accounts of cognition and semantic reference. (shrink)

This manuscript develops a relational, processual ontology in which determinacy is not presupposed as an intrinsic property of objects but emerges through structured processes of symmetry breaking, constraint formation, and synchronization across interacting systems. Challenging classical object-centered ontology and its reliance on efficient causation, the work argues that determinacy, identity, probability, and significance arise as relational achievements. The framework is articulated in general form and then realized across three structurally distinct domains: quantum mechanics, biosemiotics, and large language models. In each (...) case, a pre-individuated field of relational possibility is differentiated through constraint; probability functions non-epistemically as a measure of relational compatibility; and stable identity emerges as a re-enterable regime of coordinated interaction. By demonstrating structural isomorphism across physical, biological, and formal computational systems, the manuscript proposes a unified ontological orientation in which determinacy is understood as the stabilization of constrained relational freedom rather than as the persistence of intrinsic entities. (shrink)

Quantum mechanics and general relativity provide incompatible descriptions of time. In QM, states evolve unitarily with respect to an external time parameter; in GR, time is a coordinate in a dynamical spacetime geometry. We propose that both quantum and relativistic time emerge from a pre-geometric structure we call Prototime (PT): represented by an orthomodular lattice of consistency relations with zero von Neumann entropy at the fundamental level. PT has no background time, space, or metric—only algebraic relations of compatibility and orthogonality. (...) We formalize PT using an orthomodular lattice Lequipped with a foliation functor F: I →Ctx(L) that maps orderedi ndices to Boolean sublattices (classical contexts). A spectral redundancy functional Φs measures coherence preservation across embeddings. We show that: 1. Stable foliations satisfying Piron-Solèr conditions admit Hilbert-space representa- tions, recovering standard QM with Schrödinger dynamics via Stone’s theorem; 2. The partial order on decoherence events across foliations, together with a natural volume measure, reconstructs Lorentzian spacetime structure; 3. Time—both quantum (parameter along unitary flows) and relativistic (causal or- der)—supervenes on Φs-monotone decoherence gradients. Critically, we provide a computationally tractable implementation of Φs using spectral graph theory on mutual information networks (Bailey and Schneider, forthcoming). Testing this on simulated multi-agent systems—including combinatorial threshold-linear networks (CTLNs) that model graph-constrained neural dynamics—we demonstrate that Φs exhibits characteristic signatures during basin formation, attractor convergence, and coherence-to-classicality transitions. These results provide the first quantitative bridge between abstract PT formalism and testable physical predictions. We identify concrete empirical tests via quantum biology (photosynthetic complexes), quantum decoherence exper- iments, and neural ensemble dynamics. We also resolve the Wheeler delayed-choice experiment within PT, where apparent retrocausality dissolves because decoherence times vary across system components, creating asymmetric basin formation that only appears backward-causal when projected onto classical time. PT thus provides a kine- matical unification of QM and GR with testable predictions, offering a pre-geometric foundation for both fundamental physics and, potentially, theories of consciousness grounded in informational irreducibility. -/- (This piece is the formalism for our “Superpsychism” piece for our forthcoming target paper at The Journal of Consciousness Studies and our paper on Spectral Phi. Comments are very welcome.). (shrink)

In this paper, we evaluate some proposals that can be advanced to clarify the ontological consequences of Relational Quantum Mechanics. We first focus on priority monism and ontic structural realism and argue that these views are not suitable for providing an ontological interpretation of the theory. Then, we discuss an alternative interpretation that we regard as more promising, based on so-called ‘metaphysical coherentism’, which we also connect to the idea of an event-based, or ‘flash’, ontology.

In this paper I present and critically discuss the main strategies that Bohr used and could have used to fend off the charge that his interpretation does not provide a clear-cut distinction between the classical and the quantum domain. In particular, in the first part of the paper I reassess the main arguments used by Bohr to advocate the indispensability of a classical framework to refer to quantum phenomena. In this respect, by using a distinction coming from an apparently unrelated (...) philosophical corner, we could say that Bohr is not a revisionist philosopher of physics but rather a descriptivist one in the sense of Strawson. I will then go on discussing the nature of the holistic link between classical measurement apparatuses and observed system that he also advocated. The oft-repeated conclusion that Bohr’s interpretation of the quantum formalism is untenable can only be established by giving his arguments as much force as possible, which is what I will try to do in the following by remaining as faithful as possible to his published work. (shrink)

This book consists in seventeen chapters devoted to physical, metaphysical, and methodological questions concerning open systems. The chapters in the volume address questions such as: Are (theories of) open systems more fundamental than (theories of) closed systems? How have concepts of open and closed systems have been used throughout the history of physics, and how should we understand their use in contemporary physical theories? Must the universe be a closed system? Must there be a such thing as the universe at (...) all? -/- Contributors: Emily Adlam, Luis C. Barbado, Caslav Brukner, Eddy Keming Chen, Michael E. Cuffaro, Gemma De les Coves, George Ellis, Doreen Fraser, Henrique Gomes, Sean Gryb, William L. Harper, Stephan Hartmann, Molly Kao, Adam Koberinski, James Ladyman, Simon Langenscheidt, Olimpia Lombardi, Jorn Klovfjell Mjelva, Wayne C. Myrvold, Daniele Oriti, Josh Quirke, David Sloan, Karim P. Y. Thebault, Lev Vaidman, David Wallace, and Alastair Wilson. (shrink)

I argue here that progress in understanding the lessons of quantum physics has been hindered by the tendency to cast Niels Bohr as a villain. Building on the work of Favrholdt, Faye, and Howard, I present a more accurate view of Bohr's proposal for the "epistemological lesson" of quantum physics. I then argue that several interpretive programs -- often presented as alternatives to Copenhagen -- are, after substantial conceptual work, arriving at a view that is notably similar to Bohr's. -/- (...) Using Maudlin’s formulation of the measurement problem as a foil, I argue that it relies on a notion of wave-function completeness that is inappropriate for a genuinely indeterministic theory, and one that Bohr consistently rejected. On Bohr's view, quantum theory permits concrete agents, situated within specific experimental contexts, to make objective descriptions, while refusing the demand for a single, context-free "description from nowhere". (shrink)

This paper explores relational environmental ethics, focusing on interdependence as a basis for moral duty. Interdependence is here understood as causal interactions, and I argue that it is not a necessary condition for environmental moral duty. I demonstrate this through a ‘dwarven world’ thought experiment, showing that ethical duties can persist even when human-nature interdependence is minimal. I further propose a spectatorial-sentimentalist framework for relational moral duty of care. This framework, grounded in impartial spectator approval, reconciles universal moral demands with (...) subjective sentiments. This analysis provides a more robust and adaptable theoretical foundation for relational environmental ethics. (shrink)

Atomic stability is one of the most firmly established results of quantum mechanics. The spectral and variational formalism rigorously accounts for the impossibility of electronic collapse into the nucleus. However, this explanation remains primarily structural: it establishes an energetic constraint without explicitly identifying the physical mediation responsible for making such stability effective. This study adopts an explicit ontological perspective according to which physical stability presupposes the existence of real mediation. It explores the hypothesis that the quantum vacuum — understood not (...) merely as an abstract ground state but as a physically structurable substrate — may admit local topological organizations capable of mediating atomic stability. Within this framework, a dynamic vacuum vortex is proposed as a structural hypothesis compatible with quantum field theory. A minimal variational formalization indicates that a topologically stable configuration can be introduced without contradicting currently known experimental constraints. The aim of this contribution is not to modify the predictive framework of quantum mechanics, but rather to open a research program oriented toward a deeper causal intelligibility of quantum phenomena. This approach aligns with a critical scientific realist perspective and suggests that quantum mechanics may represent an effective description of a deeper dynamical organization of the vacuum. (shrink)

The standard formulation of Relational Quantum Mechanics (RQM) models events through projective measurements, thereby importing idealisations that fail to capture generalized quantum measurements. We show that this limitation is not intrinsic to RQM but to the PVM framework. By identifying relational events with effects—the elements of POVMs that encode physically implemented interactions—RQM becomes fully POVM-native. Events are effect-ascriptions, and relational state updates follow the general Kraus rule, with no appeal to projectors or Hilbert-space dilations. This reformulation constitutes an initial step (...) toward dissolving the “Problem of Generic Measurements” recently raised by Calosi and Riedel [11], thereby naturally accommodating weak, noisy, and continuous measurements. We conclude our analysis by identifying at least three possible metaphysical candidates for our POVM-native formulation of RQM. (shrink)

Since its inception in 1996, Rovelli’s Relational Quantum Mechanics (RQM) has left the status of non-interacting systems notably underexplored. When discussed at all, one prevailing view has maintained that attributing properties to isolated systems within RQM is simply meaningless. However, it has become increasingly evident that without a satisfying account of non-interacting systems, RQM risks sliding toward antirealist interpretations–at least insofar as such systems are concerned. In response to this crucial challenge, two main approaches have been advanced. One is a (...) form of dispositionalism, which suggests that isolated physical systems possess only dispositional properties. The other appeals to a determinable-based account of metaphysical indeterminacy, suggesting that a non-interacting quantum system may bear a determinable property without possessing any unique determinate of that determinable at a given time. In this paper, we offer a new response to the question of what can be meaningfully said about quantum systems prior to measurement in the context of RQM. In particular, drawing on the formalism of Positive Operator-Valued Measures (POVMs), we emphasize that (1) preparation–like measurement–constitutes a physical interaction capable of assigning relational properties to a system, and that (2) POVMs are indispensable for the proper description of observables with continuous spectra. On this basis, we propose that RQM can accommodate an entity-realist interpretation of non-interacting systems by attributing to them what we term relational unsharp properties. As we will show, this theoretical move preserves the relational nucleus of RQM while enabling a physically and philosophically coherent account of non-interacting quantum systems. (shrink)

The relational interpretation of quantum mechanics (RQM) has generated intense philosophical debate, particularly regarding its distinctive conception of knowledge. This paper examines how RQM articulates that conception through the notion of “information.” I begin by analyzing Carlo Rovelli’s view of scientific knowledge, followed by a reconstruction of the main argument supporting RQM. I then critically assess how the theory connects information and knowledge to present a realist, naturalist, and relational account of science. I argue that, in its current form, RQM (...) fails to offer a coherent epistemological framework. Moreover, recent attempts by its advocates to resolve these issues expose deep philosophical tensions at the core of the interpretation, indicating the need for substantial theoretical revisions. (shrink)

Relational quantum mechanics (RQM) explains the world in terms of an ontology of systems and events, where an event consists of a variable of a system taking a value relative to another system. Two strands of RQM may be distinguished depending on whether events are taken to be absolute or relative. The arguments in this paper apply to both, although I assume that the relativity is not infinitely iterated. I argue that, to solve the problem of measurement, RQM needs to (...) offer a specification of the circumstances in which events occur. Current formulations of RQM claim that events occur whenever interactions occur, without further defining what is meant by “interaction”. I develop plausible ways of understanding the notion of interaction, but I show that they fail to provide a satisfactory specification for the occurrence of events. RQM thus leaves the measurement problem unresolved and, in light of these failed constructive efforts, I conclude that developing a solution consistent with the aims of RQM is a formidable challenge. (shrink)

Perspectivist positions have been proposed in physics, notably in order to address the interpretive difficulties of quantum mechanics. Recently, some versions of perspectivism have also been proposed in general philosophy of science to account for the plurality of scientific practice. Both kinds of views share the rejection of what they metaphorically call the “view from nowhere”. However, beyond this superficial similarity, they are very different: while quantum perspectivism entertains a concrete notion of perspective associated with individual agents or systems or (...) concrete contexts, perspectival realism adopts a more abstract notion associated with explanatory aims or conceptual schemes. The aim of this paper is to clarify what is at stake with perspectivism _in general_. The general notion of a perspective, as well as the various attitudes one can entertained towards them, are characterised using the concepts of harmless contradiction and cross-perspectival accessibility. A taxonomy of positions ranging from absolutism to relativism is proposed on this basis. Then the framework is applied to quantum perspectivism and perspectival realism to show its fruitfulness. Finally, I argue that abstract versions of perspectivism are bound to be metaphysically weaker than concrete versions. (shrink)

Quantum Mechanics is arguably the most controversial theory ever constructed: its overwhelming empirical success contrasts with the perplexity about its basic meaning. Darwin's evolutionary theory, on the other side, is hailed as the only conceptual framework that allows us to make sense of biological phenomena, at the same time its theoretical efficiency has been overly debated. Although both quantum physics and evolutionary theory constitute a scientific bedrock in contemporary thinking, a deeper analysis of their relationship is still missing. In the (...) following paper I will address the connection between Darwinism and a specific interpretation of quantum mechanics proposed by Carlo Rovelli, namely, Relational Quantum Mechanics. I will aim to show that Darwinism (understood in a broad sense) has constituted a central source of inspiration for Rovelli's own proposal, in three different ways: first, Darwinism provides a model of a philosophically satisfactory scientific theory; second, it introduces a way of thinking at odds with traditional substantialism; and third, it stresses the central and unifying role of information. (shrink)

Relational quantum mechanics (RQM) is an interesting alternative to the standard responses to the measurement problem in quantum mechanics. But it suffers from a distinctive kind of epistemic solipsism: an observer can’t in principle know anything beyond their immediate present experience. This makes RQM self-undermining: it takes away the evidence we have for believing in quantum mechanics in the first place. Recently, Adlam and Rovelli have proposed a solution to this problem in the form of a new postulate they call (...) cross-perspective links. Here I argue that this postulate does indeed solve the skeptical problem, but it also removes those aspects of RQM that make it distinctively relational. Nevertheless, the result of equipping RQM with cross-perspective links is an interesting interpretation in its own right. (shrink)

The idea that the dynamical properties of quantum systems are invariably relative to other systems has recently regained currency. Using Relational Quantum Mechanics (RQM) for a case study, this paper calls attention to a question that has been underappreciated in the debate about quantum relativism: the question of whether relativity iterates. Are there absolute facts about the properties one system possesses relative to a specified reference, or is this again a relative matter, and so on? It is argued that RQM (...) (in its best-known form) is committed to what I call the Unrestricted Iteration Principle (UIP), and thus to an infinite regress of relativisations. This principle plays a crucial role in ensuring the communicability and coherence of interaction outcomes across observers. It is, however, shown to be incompatible with the widespread, conservative reading of RQM in terms of relations, instead necessitating the adoption of the more unorthodox notion of perspectival facts. I conclude with some reflections on the current state of play in perspectivist versions of RQM and quantum relativism more generally, underscoring both the need for further conceptual development and the importance of the iteration principle for an accurate cost-benefit analysis of such interpretations. (shrink)

In recent works, Časlav Brukner and Jacques Pienaar have raised interesting objections to the relational interpretation of quantum mechanics. We answer these objections in detail and show that, far from questioning the viability of the interpretation, they sharpen and clarify it.

In this paper, we evaluate some proposals that have been put forward to clarify the ontological consequences of relational quantum mechanics. We first focus on priority monism and ontic structural realism and argue that these views are not suitable for providing an ontological interpretation of the theory. Then, we discuss an alternative interpretation that we regard as more promising, based on so-called ‘metaphysical coherentism’, which we also connect to the idea of an event-based, or ‘flash’, ontology.

In the literature on the interpretation of quantum mechanics, not many works attempt to adopt a proactive perspective aimed at seeing how different interpretations can enrich each other through a productive dialogue. In particular, few proposals have been devised to show that different approaches can be clarified by comparing them, and can even complement each other, improving or leading to a more fertile overall approach. The purpose of this paper is framed within this perspective of complementation and mutual enrichment. In (...) particular, the Relational Quantum Mechanics and the Modal-Hamiltonian Interpretation are compared, highlighting their differences and points of contact. The final purpose is to show that, in spite of their disagreements, they are not contradictory but, on the contrary, they can be made compatible from an overarching perspective and can even complement each other in a fruitful way. (shrink)

Facts happen at every interaction, but they are not absolute: they are relative to the systems involved in the interaction. Stable facts are those whose relativity can effectively be ignored. In this work, we describe how stable facts emerge in a world of relative facts and discuss their respective roles in connecting quantum theory and the world. The distinction between relative and stable facts resolves the difficulties pointed out by the no-go theorem of Frauchiger and Renner, and is consistent with (...) the experimental violation of the Local Friendliness inequalities of Bong et al.. Basing the ontology of the theory on relative facts clarifies the role of decoherence in bringing about the classical world and solves the apparent incompatibility between the ‘linear evolution’ and ‘projection’ postulates. (shrink)

Relational Quantum Mechanics is an interpretation of quantum mechanics proposed by Carlo Rovelli. Rovelli argues that, in the same spirit as Einstein’s theory of relativity, physical quantities can only have definite values relative to an observer. Relational Quantum Mechanics is hereby able to offer a principled explanation of the problem of nested measurement, also known as Wigner’s friend. Since quantum states are taken to be relative states that depend on both the system and the observer, there is no inconsistency in (...) the descriptions of the observers. Federico Laudisa has recently argued, however, that Rovelli’s description of Wigner’s friend is ambiguous, because it does not take into account the correlation between the observer and the quantum system. He argues that if this correlation is taken into account, the problem with Wigner’s friend disappears and, therefore, a relativization of quantum states is not necessary. I will show that Laudisa’s criticism is not justified. To the extent that the correlation can be accurately reflected, the problem of Wigner’s friend remains. An interpretation of quantum mechanics that provides a solution to it, like Relational Quantum Mechanics, is therefore a welcome one. (shrink)

Building on self-professed perspectival approaches to both scientific knowledge and causation, I explore the potentially radical suggestion that perspectivalism can be extended to account for a type of objectivity in science. Motivated by recent claims from quantum foundations that quantum mechanics must admit the possibility of observer-dependent facts, I develop the notion of ‘perspectival objectivity’, and suggest that an easier pill to swallow, philosophically speaking, than observer-dependency is perspective-dependency, allowing for a notion of observer-independence indexed to an agent perspective. Working (...) through the case studies of colour perception and causal perspectivalism, I identify two places within which I claim perspectival objectivity is already employed, and make the connection to quantum mechanics through Bohr’s philosophy of quantum theory. I contend that perspectival objectivity can ensure, despite the possibility of perspective-dependent scientific facts, the objectivity of scientific inquiry. (shrink)

This publication is an appreciation of the natural philosophy and epistemology of the philosopher Grete (Henry-)Hermann. A student of the mathematician Emmy Noether and the philosopher Leonard Nelson, she was one of the early interpreters of quantum mechanics. Werner Heisenberg memorialized her in his book "The Part and the Whole". For the first time, her writings on natural philosophy and epistemology are collected in one volume. An extensive introduction by various authors introduces the work of Grete Henry-Hermann. This edition is (...) supplemented by excerpts from correspondence on natural philosophical and epistemological topics, including correspondence with Carl Friedrich von Weizsäcker, Werner Heisenberg, and Gustav Heckmann. Contents ● Grete Henry-Hermann's contribution to the interpretation of quantum mechanics ● Grete Henry-Hermann's work on the relationship between modern physics and transcendental philosophy ● Grete Hermann's dissertation: The Question of the Finitely Many Steps in the Theory of Polynomial Ideals (1925) ● Discussions on the question of free will and the significance of behavioral research for the critique of reason ● Excerpts from correspondence from 1925 to 1982. (shrink)

The relational interpretation of quantum mechanics proposes to solve the measurement problem and reconcile completeness and locality of quantum mechanics by postulating relativity to the observer for events and facts, instead of an absolute “view from nowhere”. The aim of this paper is to clarify this interpretation, and in particular, one of its central claims concerning the possibility for an observer to have knowledge about other observer’s events. I consider three possible readings of this claim, and develop the most promising (...) one, relativism, to show how it fares when confronted with the traditional interpretative problems of quantum mechanics. Although it provides answers to some problems, I claim that there is currently no adapted locality criterion to evaluate whether the resulting interpretation is local or not. (shrink)

In 2005, an essay was published in Nature asserting that the universe is mental and that we must abandon our tendency to conceptualize observations as things. Since then, experiments have confirmed that — as predicted by quantum mechanics — reality is contextual, which contradicts at least intuitive formulations of realism and corroborates the hypothesis of a mental universe. Yet, to give this hypothesis a coherent rendering, one must explain how a mental universe can — at least in principle — accommodate (...) (a) our experience of ourselves as distinct individual minds sharing a world beyond the control of our volition; and (b) the empirical fact that this world is contextual despite being seemingly shared. By combining a modern formulation of the ontology of idealism with the relational interpretation of quantum mechanics, the present paper attempts to provide a viable explanatory framework for both points. In the process of doing so, the paper also addresses key philosophical qualms of the relational interpretation. (shrink)

In this article we present a possible way to make usual quantum mechanics fully compatible with physical realism, defined as the statement that the goal of physics is to study entities of the natural world, existing independently from any particular observer’s perception, and obeying universal and intelligible rules. Rather than elaborating on the quantum formalism itself, we propose a new quantum ontology, where physical properties are attributed jointly to the system, and to the context in which it is embedded. In (...) combination with a quantization principle, this non-classical definition of physical reality sheds new light on counter-intuitive features of quantum mechanics such as the origin of probabilities, non-locality, and the quantum-classical boundary. (shrink)

Fifteen philosophers offer new essays exploring the metaphysics of relations from antiquity to the present day. They address topics as diverse as ancient and medieval reasons for scepticism about polyadic properties; recent attempts to reduce causal and spatiotemporal relations; recent work on the directionality of relational properties; powers ontologies and their associated problems; whether the most promising interpretations of quantum mechanics posit a fundamentally relational world; and whether the very idea of such a world is coherent. From those who question (...) whether there are relational properties at all, to those who hold they are a fundamental part of reality, The Metaphysics of Relations covers a broad spectrum of positions on the nature and ontological status of relations, from antiquity to the present day. (shrink)

All the typical global quantum mechanical observables are complex relative phases obtained by interference phenomena. They are described by means of some global geometric phase factor, which is thought of as the “memory” of a quantum system undergoing a “cyclic evolution” after coming back to its original physical state. The origin of a geometric phase factor can be traced to the local phase invariance of the transition probability assignment in quantum mechanics. Beyond this invariance, transition probabilities also remain invariant under (...) the operation of complex conjugation. Most important, geometric phase factors distinguish between unitary and antiunitary transformations in terms of complex conjugation. These two types of invariance functions as an anchor point to investigate the role of loops and based loops in the state space of a quantum system as well as their links and interrelations. We show that arbitrary transition probabilities can be calculated using projective invariants of loops in the space of rays. The case of the double slit experiment serves as a model for this purpose. We also represent the action of one-parameter unitary groups in terms of oppositely oriented-based loops at a fixed ray. In this context, we explain the relation among observables, local Boolean frames of projectors, and one-parameter unitary groups. Next, we exploit the non-commutative group structure of oriented-based loops in 3-d space and demonstrate that it carries the topological semantics of a Borromean link. Finally, we prove that there exists a representation of this group structure in terms of one-parameter unitary groups that realizes the topological linking properties of the Borromean link. (shrink)

In the first part of the paper I argue that an ontology of events is precise, flexible and general enough so as to cover the three main alternative formulations of quantum mechanics as well as theories advocating an antirealistic view of the wave function. Since these formulations advocate a primitive ontology of entities living in four-dimensional spacetime, they are good candidates to connect that quantum image with the manifest image of the world. However, to the extent that some form of (...) realism about the wave function is also necessary, one needs to endorse also the idea that the wave function refers to some kind of power. In the second part, I discuss some difficulties raised by the recent proposal that in Bohmian mechanics this power is holistically possessed by all the particles in the universe. (shrink)

This unique book provides a self-contained conceptual and technical introduction to the theory of differential sheaves. This serves both the newcomer and the experienced researcher in undertaking a background-independent, natural and relational approach to "physical geometry". In this manner, this book is situated at the crossroads between the foundations of mathematical analysis with a view toward differential geometry and the foundations of theoretical physics with a view toward quantum mechanics and quantum gravity. The unifying thread is provided by the theory (...) of adjoint functors in category theory and the elucidation of the concepts of sheaf theory and homological algebra in relation to the description and analysis of dynamically constituted physical geometric spectrums. (shrink)

The framework of quantum frames can help unravel some of the interpretive difficulties i the foundation of quantum mechanics. In this paper, I begin by tracing the origins of this concept in Bohr's discussion of quantum theory and his theory of complementarity. Engaging with various interpreters and followers of Bohr, I argue that the correct account of quantum frames must be extended beyond literal space–time reference frames to frames defined by relations between a quantum system and the exosystem or external (...) physical frame, of which measurement contexts are a particularly important example. This approach provides superior solutions to key EPR-type measurement and locality paradoxes. (shrink)

Foundations of Relational Realism presents an intuitive interpretation of quantum mechanics, based on a revised decoherent histories interpretation, structured within a category theoretic topological formalism. -/- If there is a central conceptual framework that has reliably borne the weight of modern physics as it ascends into the twenty-first century, it is the framework of quantum mechanics. Because of its enduring stability in experimental application, physics has today reached heights that not only inspire wonder, but arguably exceed the limits of intuitive (...) vision, if not intuitive comprehension. For many physicists and philosophers, however, the currently fashionable tendency toward exotic interpretation of the theoretical formalism is recognized not as a mark of ascent for the tower of physics, but rather an indicator of sway—one that must be dampened rather than encouraged if practical progress is to continue. -/- In this unique two-part volume, designed to be comprehensible to both specialists and non-specialists, the authors chart out a pathway forward by identifying the central deficiency in most interpretations of quantum mechanics: That in its conventional, metrical depiction of extension, inherited from the Enlightenment, objects are characterized as fundamental to relations—i.e., such that relations presuppose objects but objects do not presuppose relations. The authors, by contrast, argue that quantum mechanics exemplifies the fact that physical extensiveness is fundamentally topological rather than metrical, with its proper logico-mathematical framework being category theoretic rather than set theoretic. -/- By this thesis, extensiveness fundamentally entails not only relations of objects, but also relations of relations. Thus, the fundamental quanta of quantum physics are properly defined as units of logico-physical relation rather than merely units of physical relata as is the current convention. Objects are always understood as relata, and likewise relations are always understood objectively. In this way, objects and relations are coherently defined as mutually implicative. The conventional notion of a history as “a story about fundamental objects” is thereby reversed, such that the classical “objects” become the story by which we understand physical systems that are fundamentally histories of quantum events. -/- These are just a few of the novel critical claims explored in this volume—claims whose exemplification in quantum mechanics will, the authors argue, serve more broadly as foundational principles for the philosophy of nature as it evolves through the twenty-first century and beyond. (shrink)

We propose a sheaf-theoretic framework for the representation of a quantum observable structure in terms of Boolean information sieves. The algebraic representation of a quantum observable structure in the relational local terms of sheaf theory effectuates a semantic transition from the axiomatic set-theoretic context of orthocomplemented partially ordered sets, la Birkhoff and Von Neumann, to the categorical topos-theoretic context of Boolean information sieves, la Grothendieck. The representation schema is based on the existence of a categorical adjunction, which is used as (...) a theoretical platform for the development of a functorial formulation of information transfer, between quantum observables and Boolean localisation devices in typical quantum measurement situations. We also establish precise criteria of integrability and invariance of quantum information transfer by cohomological means. (shrink)

Carlo Rovelli's relational interpretation of quantum mechanics holds that a system's states or the values of its physical quantities as normally conceived only exist relative to a cut between a system and an observer or measuring instrument. Furthermore, on Rovelli's account, the appearance of determinate observations from pure quantum superpositions happens only relative to the interaction of the system and observer. Jeffrey Barrett ([1999]) has pointed out that certain relational interpretations suffer from what we might call the ‘determinacy problem', but (...) Barrett misclassifies Rovelli's interpretation by lumping it in with Mermin's view, as Rovelli's view is quite different and has resources to escape the particular criticisms that Barrett makes of Mermin's view. Rovelli's interpretation still leaves us with a paradox having to do with the determinacy of measurement outcomes, which can be accepted only if we are willing to give up on certain elements of the ‘absolute’ view of the world. (shrink)

The underlying physical reality is a central notion in the interpretations of quantum mechanics. The a priori physical reality notion affects the corresponding interpretation. This paper explore the possibility to establish a relationship between philosophical concept of physical reality in Nagarjuna's epistemology (emptiness) and the picture of underlying physical reality in Einstein, Rovelli and Zeilinger positions. This analysis brings us to conclude that the notion of property of a quantum object is untenable. We can only speak about relational property of (...) the object. On this basis, we are stimulated to build a new ontology of underlying physical reality: a relational ontology. Finally, we argue that Nagarjuna's view is comparable with Rovelli's interpretation of quantum mechanics. These views eliminate the privileged role of the observer. (shrink)

Pekka Lahti is a prominent exponent of the renaissance of foundational studies in quantum mechanics that has taken place during the last few decades. Among other things, he and coworkers have drawn renewed attention to, and have analyzed with fresh mathematical rigor, the threat of inconsistency at the basis of quantum theory: ordinary measurement interactions, described within the mathematical formalism by Schrödinger-type equations of motion, seem to be unable to lead to the occurrence of definite measurement outcomes, whereas the same (...) formalism is interpreted in terms of probabilities of precisely such definite outcomes. Of course, it is essential here to be explicit about how definite measurement results (or definite properties in general) should be represented in the formalism. To this end Lahti et al. have introduced their objectification requirement that says that a system can be taken to possess a definite property if it is certain (in the sense of probability 1) that this property will be found upon measurement. As they have gone on to demonstrate, this requirement entails that in general definite outcomes cannot arise in unitary measuring processes.In this paper we investigate whether it is possible to escape from this deadlock. As we shall argue, there is a way out in which the objectification requirement is fully maintained. The key idea is to adapt the notion of objectivity itself, by introducing relational or perspectival properties. It seems that such a “relational perspective” offers prospects of overcoming some of the long-standing problems in the interpretation of quantum mechanics. (shrink)

By the relational realist interpretation of wave function collapse, the quantum mechanical actualization of potential outcome states is defined as a decoherence-driven process by which each actualization (in “orthodox” terms, each measurement outcome) is conditioned both by physical and logical relations with the actualities conventionally demarked as “environmental” or external to that particular outcome. But by the relational realist interpretation, the actualization-in-process is understood as internally related to these “enironmental” data per the formalism of quantum decoherence. The concept of “actualization (...) via wave function collapse” is accounted for solely by virtue of these presupposed logical relations—the same logical relations otherwise presupposed by the scientific method itself—and thus requires no “external” physical-dynamical trigger: e.g., the Gaussian hits of GRW, acts of conscious observation, etc. By the relational realist interpretation, it is the physical and logical relations among quantum actualities (quantum “final real things”) that drives the process of decoherence and, via the latter, the logically conditioned actualization of potentia. In this regard, the relational realist interpretation of quantum mechanics is a praxiological interpretation; that is, these physical and logical relations are ontologically active relations, contributing not just to the epistemic coordination of quantum actualizations, but to the process of actualization itself. (shrink)

The Relational Blockworld (RBW) interpretation of non-relativistic quantum mechanics (NRQM) is introduced. Accordingly, the spacetime of NRQM is a relational, non-separable blockworld whereby spatial distance is only defined between interacting trans-temporal objects. RBW is shown to provide a novel statistical interpretation of the wavefunction that deflates the measurement problem, as well as a geometric account of quantum entanglement and non-separability that satisfies locality per special relativity and is free of interpretative mystery. We present RBW’s acausal and adynamical resolution of the (...) so-called “quantum liar paradox,” an experimental set-up alleged to be problematic for a spacetime conception of reality, and conclude by speculating on RBW’s implications for quantum gravity. (shrink)

We construct a sheaf-theoretic representation of quantum observables algebras over a base category equipped with a Grothendieck topology, consisting of epimorphic families of commutative observables algebras, playing the role of local arithmetics in measurement situations. This construction makes possible the adaptation of the methodology of Abstract Differential Geometry (ADG), à la Mallios, in a topos-theoretic environment, and hence, the extension of the “mechanism of differentials” in the quantum regime. The process of gluing information, within diagrams of commutative algebraic localizations, generates (...) dynamics, involving the transition from the classical to the quantum regime, formulated cohomologically in terms of a functorial quantum connection, and subsequently, detected via the associated curvature of that connection. (shrink)