The predictive success of modern physics from rigid body mechanics to quantum field theory stands among the greatest achievements of the human mind. Yet this success does not necessarily entail completeness of explanatory understanding. This paper investigates the epistemological gap between mathematical description and causal explanation, taking the behavior of rotating bodies (gyroscopes) as a preliminary example, then extending to two central problems: the measurement problem in quantum mechanics and the nature of mass in particle physics. The study shows that concepts such as angular momentum and precession, despite their predictive accuracy, redescribe phenomena in mathematical language more than they provide intuitive causal mechanisms. It also demonstrates that Noether’s theorem and the principle of least action, for all their depth, reformulate fundamental questions rather than resolving them. The paper discusses the framework of structural realism as a philosophical stance that accommodates this gap, examines criticisms of this framework (the problem of structural individuation and the problem of abandoned theories), and concludes that acknowledging this gap is not an attack on physics but a condition for its philosophical maturity.
The predictive success of modern physics from rigid body mechanics to quantum field theory stands among the greatest achievements of the human mind. Yet this success does not necessarily entail completeness of explanatory understanding. This paper investigates the epistemological gap between mathematical description and causal explanation, taking the behavior of rotating bodies (gyroscopes) as a preliminary example, then extending to two central problems: the measurement problem in quantum mechanics and the nature of mass in particle physics. The study shows that concepts such as angular momentum and precession, despite their predictive accuracy, redescribe phenomena in mathematical language more than they provide intuitive causal mechanisms. It also demonstrates that Noether’s theorem and the principle of least action, for all their depth, reformulate fundamental questions rather than resolving them. The paper discusses the framework of structural realism as a philosophical stance that accommodates this gap, examines criticisms of this framework (the problem of structural individuation and the problem of abandoned theories), and concludes that acknowledging this gap is not an attack on physics but a condition for its philosophical maturity.
Contemporary physics relies extensively on mathematical formalisms to describe natural phenomena, often achieving remarkable predictive success. However, the relationship between mathematical description and physical explanation remains a subject of ongoing debate. In many cases, mathematical models are treated not only as tools for representation but also as implicit substitutes for the underlying physical mechanisms, which can obscure questions of causality and physical origin. This article examines this methodological issue using two fundamental physical phenomena—gravity and the tunneling effect— as representative examples. Both phenomena are commonly described by highly successful mathematical frameworks, namely general relativity and quantum mechanics, yet their physical interpretations remain incomplete or debated. The work argues that predictive accuracy alone does not necessarily constitute a full physical explanation and that mathematical consistency should be complemented by physically grounded mechanisms based on observable properties of matter and interaction. Alternative descriptions of gravity and the tunneling effect are proposed, grounded in experimental observations and established physical properties of matter at macroscopic and microscopic scales. These descriptions aim to clarify the physical processes underlying the phenomena while remaining compatible with empirical data. The proposed framework does not reject existing theories but seeks to supplement them by addressing conceptual gaps related to causality, physical mechanism, and interpretation. Such an approach may contribute to a more physically transparent understanding of fundamental phenomena and provide new directions for theoretical and applied research.
Quantum mechanics has achieved unparalleled success as an operational theory, describing a wide range of experiments to remarkable accuracy. However, the physical foundations on which it rests remain as puzzling as they were a century ago, and a concise statement of the physical principles that underlie quantum mechanics is still outstanding. One promising approach holds that these principles should be formulated in terms of information, since many of the counter-intuitive effects in quantum theory concern questions such as what one can know about a quantum system and how the information encoded therein can be processed and distributed between parties. Another challenging feature of quantum theory is its incompatibility with the other cornerstone of modern physics, general relativity. In order to reconcile the two, one must identify and retain only the essential concepts and principles of each theory, and in the case of general relativity, causality has been identified as such a concept. This raises the question of how our classical understanding of causality must change when quantum theory is taken into account. In order to address these questions about information, knowledge and causality, I turn to the framework of causal models. In classical statistics, causal models explain the relations among a set of variables in terms of causal influences, which makes them a powerful tool for structuring our knowledge about complex systems and developing strategies for interacting with them. More importantly, the framework provides the conceptual underpinnings and mathematical methods for addressing questions about causation, information and knowledge in a rigorous manner. In this thesis, I develop a version of the classical causal models framework that is compatible with quantum theory and explore its physical implications. \n \n \nA first step is to define quantum versions of fundamental elements such as variables, conditionals and belief propagation rules. This allows one to consider the question of what one can come to know about a quantum variable from the point of view of causal modelling. The conditionals relating quantum variables are found to have a richer structure than their classical counterparts, which can be exploited for the task of discerning causal relations given limited data -- a central problem in classical causal modelling. The mathematical properties of quantum conditionals also establish a correspondence between various classes of two-party correlations, such as bound and distillable entanglement, and the types of causal structures that can give rise to them, which may become a useful tool for entanglement theory and quantum information processing. In the context of open quantum systems dynamics, quantum causal models provide a clear physical explanation of not completely positive maps and, more broadly, of non-Markovian quantum dynamics. Finally, I consider the possibility of non-classical effects in the way that different causal mechanisms are combined -- that is, non-classical causal structures. For the simple case of two causally ordered variables, I propose indicators that witness different classes of combinations of causal mechanisms, including a non-classical mixture, and describe an experiment realizing examples of the different classes. \n \n \nAs these results illustrate, the framework of quantum causal models provides both greater conceptual clarity and a comprehensive mathematical formalism for studying a diverse set of problems, ranging from foundational questions to applications in open systems dynamics and the exploration of non-classical causal structures, which are likely to feature in a future theory of quantum gravity. The material presented in this thesis is intended as a foundation and inspiration for further applications of quantum causal models.
Quantum mechanics is often perceived as conceptually paradoxical because it appears to conflict with deeply rooted intuitions about fixed reality, determinism, and observation. This paper does not propose a new physical theory. Instead, it offers an epistemological reframing of quantum mechanics: not as a direct mathematical unveiling of a fully fixed pre-existing reality, but as a highly precise description of phenomenological structures emerging through observational conditions and interaction. The paper explores: the distinction between mathematical predictive success and ontological completeness, the role of human perception in constructing “fixed reality” intuitions, the phenomenological nature of qualities such as color and temperature, the possibility that some conceptual tensions in quantum mechanics arise from assumptions inherited from macroscopic cognition, and how quantum theory may be interpreted as describing observable structures rather than fixed hidden states. The work intentionally avoids mystical, anti-scientific, or consciousness-centric interpretations of quantum mechanics. It does not deny the existence of reality, nor reject modern physics. Rather, it attempts to clarify what exactly mathematical models are describing when applied to quantum phenomena. This text is positioned as a conceptual and phenomenological reorganization of perspective — a small doorway toward reconsidering how humans frame “reality” itself.
This article examines some experimental conditions that invite and possibly require recourse to quantum-mechanical-like mathematical models (QMLMs), models based on the key mathematical features of quantum mechanics, in scientific fields outside physics, such as biology, cognitive psychology, or economics. In particular, I consider whether the following two correlative features of quantum phenomena that were decisive for establishing the mathematical formalism of quantum mechanics play similarly important roles in QMLMs elsewhere. The first is the individuality and discreteness of quantum phenomena, and the second is the irreducibly probabilistic nature of our predictions concerning them, coupled to the particular character of the probabilities involved, as different from the character of probabilities found in classical physics. I also argue that these features could be interpreted in terms of a particular form of epistemology that suspends and even precludes a causal and, in the first place, realist description of quantum objects and processes. This epistemology limits the descriptive capacity of quantum theory to the description, classical in nature, of the observed quantum phenomena manifested in measuring instruments. Quantum mechanics itself only provides descriptions, probabilistic in nature, concerning numerical data pertaining to such phenomena, without offering a physical description of quantum objects and processes. While QMLMs share their use of the quantum-mechanical or analogous mathematical formalism, they may differ by the roles, if any, the two features in question play in them and by different ways of interpreting the phenomena they considered and this formalism itself. This article will address those differences as well.
Two mysteries -loosely connected?The Authors who have suggested a deep connection between the solution of the mind-body problem and the understanding of quantum mechanics are too numerous to list.But what exactly would be the alleged structural fit between these two deeply puzzling theoretical issues?Can a genuine philosophical issue -which by its very nature is conceptual in nature -ultimately be resolved by advances in the empirical sciences?The connection is all too often asserted to lie in the subjects confounding natures, but the mere fact that two problems are of equal impenetrability to the human mind does not imply that there is a profound interdependence between the two.There is however an obvious way in which quantum mechanics might have a bearing on the philosophical mind-body problem: if quantum mechanics implies that for some physical events there is no physical cause, then at least the very strong variants of the so-called "principle of causal closure" of the physical realm lose much of their corroborative underpinning in physics as practiced by real physicists as such, and are thus constrained to the speculative physicalism advanced by metaphysicians.However, unless one assumes a strong version of the principle of sufficient reason, which would exclude chance events in principle, even events supposedly not caused by some physical cause are not immediately thereby caused by some nonphysical cause.Moreover the fact is that not all of the interpretations of quantum mechanics imply indeterministic 'choices' of events: neither the many-worlds interpretation nor a Bohmian hidden variable interpretation assume indeterminism.Even in the most obvious theoretical nexus
ABSTRACT The paper aims to bridge the history of quantum theory with its philosophical implications. The focus is not only on the scientific underpinnings of quantum mechanics (these theories emerged as ‘ad hoc’ responses to experimental anomalies) but also on the philosophical ramifications of its probabilistic nature and indeterminacy, which differ from classical realism. The paper examines Dirac's, Bell's, and modern views, focusing on how quantum mechanics (QM) challenges traditional notions of causality, objectivity, and truth while embracing epistemological and metaphysical perspectives. Debates over collapse theories and hidden variables are discussed, as well as Putnam's philosophical outlook, which includes his trenchant involvement with realism, logic, and the measurement problem. Finally, the paper proposes that QM represents a philosophical revolution that renews our understanding of reality, knowledge, and scientific explanation, rather than simply serving as a physical theory for assessing the prospects of quantum philosophy by connecting it to broader aspects such as relativity, causality, and scientific realism.