In the atomic structure, extranuclear electrons are negatively charged and protons in the nucleus are positively charged. According to Coulomb attraction, electrons should fall into protons and cause atomic collapse. However, atoms are stable in reality. Based on the essential analysis of electromagnetic interaction and universally recognized experimental facts, this paper proves that the magnetic field generated by electrons orbiting the nucleus interacts with the proton magnetic field to form an outward repulsive force, which achieves dynamic equilibrium with the inward Coulomb attraction. This is the core reason for atomic stability. Meanwhile, the cause of permanent magnets is explained as the ordered arrangement of microscopic magnetic moments.
Jiaqing Yan (Thu,) studied this question.