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.
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.
Abstract In 1921, Otto Stern conceived the idea for an experiment that would decide between a classical and a quantum description of atomic behavior, as epitomized by the Bohr–Sommerfeld–Debye model of the atom. This model entailed not only the quantization of the magnitude of the orbital electronic angular momentum but also of the projection of the angular momentum on an external magnetic field – the so‐called space quantization. Stern recognized that space quantization would have observable consequences: namely, that the magnetic dipole moment due to the orbital angular momentum would be space quantized as well, taking two opposite values for atoms whose only unpaired electron has just one quantum of orbital angular momentum. When acted upon by a suitable inhomogeneous magnetic field, a beam of such atoms would be split into two beams consisting of deflected atoms with opposite projections of the orbital angular momentum on the magnetic field. In contradistinction, if atoms behaved classically, the atomic beam would only broaden along the field gradient and have maximum intensity at zero deflection, i. e., where there would be a minimum or no intensity for a beam split due to space quantization. Stern anticipated that, although simple in principle, the experiment would be difficult to carry out – and invited Walther Gerlach to team up with him. Gerlach's realism and experimental skills together with his sometimes stubborn determination to make things work proved invaluable for the success of the Stern–Gerlach experiment (SGE). After a long struggle, Gerlach finally saw, on 8 February 1922, the splitting of a beam of silver atoms in a magnetic field. The absence of the concept of electron spin confused and confounded the interpretation of the SGE, as the silver atoms were, in fact, in a 2S state, with zero orbital and spin angular momentum. However, a key quantum feature whose existence the SGE was designed to test – namely space quantization of electronic angular momentum – was robust enough to transpire independent of whether the electronic angular momentum was orbital or due to spin. The SGE entails other key aspects of quantum mechanics such as quantum measurement, state preparation, coherence, and entanglement. Confronted with the outcome of the SGE, Stern noted: “I still have objections to the idea of beauty of quantum mechanics. But she is correct.”
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。)
Abstract We propose a phenomenological theory of spin behavior in a magnetic field, which explains from the point of view of classical physics the two-valued result of the Stern-Gerlach experiment. The behavior of the spin and intrinsic magnetic moment of an electron wave of an atom in an external magnetic field is considered. We show that in a weak magnetic field, the intrinsic magnetic moment of an electron wave is always oriented parallel to the magnetic field strength vector, while in a strong magnetic field, depending on the initial orientation of the intrinsic magnetic moment, two orientations are realized: either parallel or antiparallel to the magnetic field strength vector. Within the framework of classical electrodynamics, the calculation of the motion of an atomic beam in an inhomogeneous magnetic field is carried out, which reproduces the results of the Stern-Gerlach experiment.
The Stern-Gerlach (SG) experiment reported in 1922 was an important milestone in the history of physics. The passing of a collimated neutral beam of silver atoms through a long, strong and asymmetrical magnet caused the atoms of silver out of a horizontal slit to split roughly into two separate beams forming a hollow lip figure (as seen on a plate held normal to the beam) instead of being a filled-in lip figure as suggested by some theoretical calculations. The SG results were thought to indicate that the observed phenomenon can not be explained using classical physics. Following a classical numerical approach by the author using a double-slit geometry, results are given for a 3D numerical SG type experiment showing clearly that a binary beam splitting is possible for certain conditions using an inverse square relation as the only source of forces- thus giving the possibility of a classical interpretation to the problem. For simplicity, we use what is mathematically equivalent- a dipole of charges to represent the magnetic dipole of the atom, and sets of fixed charges or potential surfaces around the path of the beam to represent the poles of a magnet. Although not exactly following the SG setup, the present results, nonetheless, are useful in showing the clear discrete behavior that can be caused by the combination of a fixed boundary, a strong field asymmetry and the highly nonlinear mapping of the inverse square law of forces coupled with the spin direction of a particle.
A thorough motion investigation and analysis was conducted again for the original Stern-Gerlach Experiment(SGE). The analysis is still based on the assumption that the atom passing the SG apparatus is a micromagnet due to the spin of its electron, the atoms in the source beam are with an orientation distribution of its angular momentum vectors, while the spin micromagnet is in the precession induced by an inhomogeneous magnetic field. It is the precession that keeps the silver beam with narrower orientation distribution of its angular momentum vectors after passing through the inhomogeneous magnetic field. The motion relativity was introduced in the SGE between the SG apparatus and the silver source beam, which interpreted all the detection phenomena in the multi-stage SGE. The research provided a new and convincing interpretation to the SGE with full satisfaction based on the classical physics without any mysterious or counter intuitive concepts introduced compared to quantum physics.
A Stern–Gerlach experiment constructed in the spirit of the original experiment is reported that demonstrates spatial quantization for a beam of silver atoms directly to the unaided eye. Splitting of the atomic beam is seen both parallel to the magnetic field direction, as in the “usual” experiment, and in a direction mutually perpendicular to the field and atomic trajectory, which is a new transverse Stern–Gerlach effect. Splitting of up to 4 mm can be recorded visually. Calculations based on the force components acting on the atomic beams reproduce the experimental results within the experimental accuracy of ±0.3 mm.