Ronen Yavor

Nuclear physics combines predictive success with a plurality of models that represent different aspects of nuclear structure. This article examines whether an additional structural-spatial description could deepen scientific understanding without immediately improving predictive or computational performance. Through a conceptual and methodological analysis informed by philosophical accounts of scientific understanding and model pluralism, it argues that such a description may complement existing quantum-dynamical approaches. Structural description is understood as the representation of spatial relations, symmetries, and geometrical constraints, rather than the restoration of a classical picture of particles with definite positions and trajectories. Its epistemic value would depend on supporting physical inferences, connecting phenomena, or constraining possible descriptions beyond what existing models already provide. The article further considers whether a structural hypothesis formulated from explicit assumptions and physical constraints could guide the development of a dynamical model before its detailed formulation. This is proposed as a local methodological possibility consistent with quantum theory, not as a reversal of the general order of physical justification. The article thus offers a rationale for investigating structural description as a complementary source of physical understanding. It does not propose or empirically test a concrete nuclear model, and any additional predictive contribution remains to be demonstrated.

This work presents a geometric model of orbital occupation in the atom. Starting from a small number of geometric assumptions, a periodic structure is obtained in which electrons are represented as equal-sized spheres. The resulting structure provides a consistent representation of the S, P, D and F orbitals and their occupation according to the Aufbau principle and the constraints associated with the periodic table. The very possibility of obtaining, within a single geometric framework, a consistent representation that satisfies these constraints may itself be regarded as a finding worthy of consideration, even before examining the model’s correspondence with additional atomic properties. Once the geometric structure has been established, spatial coordinates are derived for the electrons and used to calculate the atomic covalent radius. The calculated radii are compared with empirical covalent-radius data for elements with even atomic numbers between 2 and 96. The results indicate a systematic correspondence between the model and the empirical data, including the reproduction of the general trends of the covalent radius across the periodic table. The agreement is stronger for low and intermediate atomic numbers and decreases for heavier elements. The covalent radius is not used in the construction of the model but rather serves as a test case for evaluating the resulting structure. Consequently, the existence of a systematic correspondence between the model predictions and covalent-radius data may suggest that the proposed geometric structure captures certain aspects of atomic regularities. These findings do not constitute proof of the physical validity of the model. However, they indicate that simple structural-geometric approaches may have value as an additional tool for examining atomic structure and its properties.

This work contributes to the philosophical analysis of reduction and unification in the physical sciences, with a focus on structural continuity across levels of physical description. It examines, within a geometric thought experiment, how spatial relations at the quark level may be represented as shaping the organization of nucleons and nuclei. The study concentrates on the transition from quarks to nucleons and to the nucleus, providing a conceptual framework for discussing structural relations between these levels. Rather than proposing an alternative to established physical theories, the model is intended as a heuristic and conceptual approach, exploring how recurring geometric patterns may underlie different levels of physical description. In this sense, the reduction proposed here is primarily explanatory: it seeks to show how complex structural features can be understood as arising from simple geometric arrangements, thereby contributing to philosophical discussions of structural realism and explanatory reduction.