Intrinsic spin is a core foundational concept of quantum mechanics and the Standard Model of particle physics. It is regarded as an inherent property of fermions, based on which core laws such as spin angular momentum conservation and lepton number conservation have been established. However, through an experimental traceability and logical deduction of the spin concept, this paper finds that the spins of electrons and protons have never been directly measured. All spin conclusions are indirectly inferred from the macroscopic magnetic effects of neutral atoms and atomic nuclei. In beta decay, protons and neutrinos with a mass difference of more than 6 orders of magnitude participate in conservation with the same spin quantum number, which is only a formal numerical matching and lacks support from real physical mechanisms. The inclusion of neutrinos in the lepton family is essentially a post-hoc expansion to satisfy conservation laws, rather than an essential classification based on the origin of matter. In response to these contradictions, this paper proposes a classical orbital circulation magnetism model: the essence of atomic magnetic moment is the circulation effect formed by electrons orbiting the nucleus, and there is no "intrinsic spin" independent of the orbit. The energy level splitting in the Stern-Gerlach experiment is the statistical result of the orientation of the instantaneous orbital angular momentum of the s orbital in a magnetic field, rather than the manifestation of the intrinsic spin of electrons. Based on this model, this paper further explains the microscopic mechanism of ferromagnetism: whether the atomic magnetic moment can be reversed by an external magnetic field depends on the degree of orbital confinement. Inner orbitals are too strongly bound to turn, while the outermost free electron orbitals have too weak coupling to maintain orientation. Only the sub-outer orbitals of iron group elements are in the critical interval of "reversible and maintainable", thus exhibiting ferromagnetism. This model can self-consistently explain related experimental phenomena without introducing ad-hoc quantum concepts such as intrinsic spin and exchange interaction, and provides an alternative explanation path of classical mechanics for electromagnetic and magnetic phenomena. (本文在英文正文后附有完整中文版,内容与结构完全一致。)
Intrinsic spin is a core foundational concept of quantum mechanics and the Standard Model of particle physics. It is regarded as an inherent property of fermions, based on which core laws such as spin angular momentum conservation and lepton number conservation have been established. However, through an experimental traceability and logical deduction of the spin concept, this paper finds that the spins of electrons and protons have never been directly measured. All spin conclusions are indirectly inferred from the macroscopic magnetic effects of neutral atoms and atomic nuclei. In beta decay, protons and neutrinos with a mass difference of more than 6 orders of magnitude participate in conservation with the same spin quantum number, which is only a formal numerical matching and lacks support from real physical mechanisms. The inclusion of neutrinos in the lepton family is essentially a post-hoc expansion to satisfy conservation laws, rather than an essential classification based on the origin of matter. In response to these contradictions, this paper proposes a classical orbital circulation magnetism model: the essence of atomic magnetic moment is the circulation effect formed by electrons orbiting the nucleus, and there is no "intrinsic spin" independent of the orbit. The energy level splitting in the Stern-Gerlach experiment is the statistical result of the orientation of the instantaneous orbital angular momentum of the s orbital in a magnetic field, rather than the manifestation of the intrinsic spin of electrons. Based on this model, this paper further explains the microscopic mechanism of ferromagnetism: whether the atomic magnetic moment can be reversed by an external magnetic field depends on the degree of orbital confinement. Inner orbitals are too strongly bound to turn, while the outermost free electron orbitals have too weak coupling to maintain orientation. Only the sub-outer orbitals of iron group elements are in the critical interval of "reversible and maintainable", thus exhibiting ferromagnetism. This model can self-consistently explain related experimental phenomena without introducing ad-hoc quantum concepts such as intrinsic spin and exchange interaction, and provides an alternative explanation path of classical mechanics for electromagnetic and magnetic phenomena. (本文在英文正文后附有完整中文版,内容与结构完全一致。)
Spin is an intrinsic form of angular momentum carried by elementary particles, composite particles, and atomic nuclei. It is wildly believed that spin is a purely quantum mechanical concept and has no classical analogue. In fact, elementary particles are conceived as point objects which have no axis to “spin” around. Therefore, there is no explaining how spin arises at the fundamental level, why particles have the values they do, and what underpins the Pauli Exclusion principle and Bose-Einstein behavior. However, spin is like a vector quantity; it has a definite magnitude, and it has a “direction”, in order to spin should be composite. In this paper we propose a physical explanation for spin of the electron at the sub-particle level, relying on the vortex model of the electron. The electron is described as a superfluid frictionless vortex which has a mass, angular momentum and spin to provide a complete explanation of all properties of the electron: it composite, spinning around its own axis, produces a tiny magnetic fields independent of those from its orbital motions. The classical hydrodynamic laws are used to describe the quantum properties of the electron, such as spin, angular momentum, magnetic momentum and a magnetic dipole. The circulation in the vortex is constant, and the angular momentum of the vortex is conserved and has the same value of Planck constant. The direction of the angular momentum of a spinning electron vortex is along the axis of rotation and determined by the direction of spin. The spin quantum number 1/2 has a fixed value which represents the gap between the circulation rate of the core of the vortex and the boundaries of the vortex. The changeable values +1/2 “spin-up” or -1/2 “spin-down” indicate the direction of the magnetic dipole of the vortex. The relation between spin and Planck constant is discussed and the origin h/4pi angular momentum units are revealed.
Since its completion in 1922, the Stern-Gerlach experiment has long been regarded in mainstream quantum mechanics as a key experimental evidence for the 1/2 intrinsic spin of electrons, and a foundational observation for spatial quantization and quantum state collapse theory. Based on the basic standpoint of the light-origin theory, this paper adheres to the core criterion that magnetism is a secondary effect derived from the directional motion of electric charges, and re-examines the phenomenon that silver atomic beams split into two streams in a non-uniform magnetic field. This paper points out that the "intrinsic spin magnetic moment" defined by mainstream quantum theory cannot correspond to closed charge circulation inside the electron (the classical rotation model leads to the contradiction of superluminal speed), and violates the unified origin principle of "electricity generating magnetism" in electromagnetism. Essentially, it is a mathematical degree of freedom artificially introduced to fit experimental results. This paper proposes that the bifurcation effect of silver atomic beams can be fully explained by the orientation coupling between magnetic dipoles formed by ordered charge circulation of electrons inside atoms and an external non-uniform magnetic field. The magnetic dipoles of incident silver atoms are randomly distributed in orientation statistically, yet only two orientations, parallel and antiparallel to the external magnetic field, can remain stable in the gradient magnetic field, while intermediate orientations are unstable and excluded. Eventually the atomic beam separates into two discrete streams, with no need to introduce the hypothesis of intrinsic spin without physical carriers. This paper further designs a discriminative experimental scheme: in a single-electron trapping system with ultra-low temperature and strong magnetic shielding, after thermal jitter is sufficiently suppressed, if no stable self-sustained static magnetic dipole signal of the electron can be detected, it will constitute a direct test for the hypothesis of intrinsic spin magnetic moment.
First, the experimental foundations for the existence of a new dynamical variable, the spin of particles, are presented. The Pauli equation is then derived in detail, two applications are given and the energy levels of a particle with spin in a constant magnetic field are studied. This is the analysis of Landau levels, which can be performed by using the known results on the spectrum of harmonic oscillators. In this chapter we also study in detail the addition of orbital angular momentum and spin, as well as the spin–orbit interaction with the resulting Thomas precession. Stern-Gerlach experiment and electron spin The hypothesis that the electron has an intrinsic magnetic moment and an angular momentum, in short a spin , was first suggested in Uhlenbeck and Goudsmit (1926). They noticed, even before the discovery of quantum mechanics, that a complete description of spectra was not possible unless a magnetic moment and a mechanical moment were ascribed to the electron, and hence the concept of an electron as a point charge was insufficient. First, let us therefore try to understand how a magnetic moment can be associated to an atomic system. For this purpose, consider for simplicity the Bohr model of an hydrogen atom, where the electron moves along a circular orbit and rotates with orbital angular momentum L .
This paper aims to provide a thorough critical analysis of two foundational concepts in modern physics — the Landé g-factor and the electron spin quantum number 1/2. Through meticulous historical examination and logical analysis, this paper argues that these concepts are essentially mathematical fitting parameters introduced to bridge the gap between the old quantum theory and experimental data, lacking a solid foundation in physical mechanism. The core contradiction lies in the subsequent development of wave mechanics, which concluded that "the orbital angular momentum of the hydrogen atom ground state is zero," a conclusion that fundamentally conflicts with observational facts such as the Stern-Gerlach experiment, forcing the spin concept to assume a "remedial" role it never needed to bear. As a solution, this paper presents a new framework based on the "Great Tao Model" and the "Unified Theory of Atomic and Molecular Structure." This framework firmly returns to the realism of classical physics, affirms the orbital motion of electrons around the nucleus and their intrinsic angular momentum, and interprets spin as a real mechanical motion. Crucially, this theory naturally derives the universal magnetic moment-angular momentum relation μ = (e/m) L from the "Existence Field" principle, eliminating the need for any artificial correction factors. Based on this, the paper successfully provides a unified and self-consistent explanation for key phenomena such as the Stern-Gerlach experiment and the normal and anomalous Zeeman effects, thereby achieving a simpler and more fundamental description of physics at the atomic scale.
This chapter discusses the prime cause of the magnetic moment within an individual atom. In the classical model, the angular momentum of the electrons can be used to determine the magnetic moments of the electrons by invoking the concept of electrical charge in motion. There are two contributions to the electronic magnetic moment: an orbital magnetic moment due to orbital angular momentum and a spin magnetic moment due to electron spin. The component of orbital angular momentum along the axis of a magnetic field is restricted to discrete values by quantum mechanics. Electrons have spin angular momentum, which can be represented by the spin quantum number. As the magnetic field is increased and the field splitting becomes greater than the multiple splitting, the anomalous Zeeman effect changes over to a normal Zeeman effect. The chapter looks at experimental evidence confirming the quantization of magnetic moments, specifically the Zeeman effect and the Stern-Gerlach experiment.
In 1925 the concept of electron spin was introduced to explain two experimental observations: the splitting of silver atom beams in an inhomogeneous magnetic field (Stern–Gerlach, 1922), and the fine structure of atomic spectra. The physical picture proposed — an electron spinning on its own axis — was immediately shown by Hendrik Lorentz to require surface velocities exceeding the speed of light. The paper was published anyway. Dirac subsequently rescued the two-valuedness mathematically, whereupon the physical question was declared irrelevant. For one hundred years the field has been unable to state what spin physically is. This paper traces the sequence of observations, inferences, and decisions that produced this situation and identifies two distinct wrong turns. The first wrong turn was publishing a model known to be physically impossible. Lorentz's calculation was correct — at the classical electron radius (2.818 fm), the required surface velocity is 274 times the speed of light. But the classical radius is not the electron's physical rotation radius. The correct rotation radius, derived from the Sagnac closure condition, is 285.5 fm — 101 times larger. At that radius, the rotation velocity is 0.822c, the bare magnetic moment is 0.608 μB, and Lorentz's objection does not arise. Both values are computed explicitly with no free parameters. The second wrong turn was a conflation. The closure geometry of the electron involves two independent numerical facts, both related to the number ½: (1) the least-work oscillation path that closes the Sagnac phase condition is a two-lobe ellipse, giving a winding number of n = ½ in the mass equation; (2) the electron's S³ closure surface presents two poles to the external field, giving a topological factor of 2 in the g-factor. In 1925, both facts were numerically present in the spectroscopic data, but they were collapsed into a single postulate: intrinsic angular momentum ℏ/2. That collapse created a half-integer angular momentum with no classical analogue, forced Dirac to construct the SU(2) spinor formalism to accommodate it, and caused the spinor to appear as a new kind of mathematical object requiring new physics — when it was always a description of closure surface topology. Every experimental result attributed to spin-½ as an intrinsic quantum property — two spots in Stern–Gerlach, the electron magnetic moment, Pauli exclusion, and fine structure — is reproduced by real rotation with two stable orientations, without superluminal motion, without abstract mathematical structure disconnected from physical content, and without the hundred-year admission of ignorance that has accompanied the standard treatment. The mathematical apparatus of quantum mechanics — the Dirac equation, the Pauli matrices, the SU(2) structure — remains valid. What changes is the interpretation. The spinor is not a mysterious new object. It is the natural representation of the two-pole topology of the S³ closure surface. The conflation of 1925 prevented this from being seen. Related work: The Sagnac closure condition and the γcause invariant used in this paper are derived in: D. J. Hallman, "The Sagnac Formula Inverted Reveals Mass, Gravity, and Particle Structure," Zenodo (2026). doi:10.5281/zenodo.20193279