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تسجيل مستخدم جديدThe current magnetization hypothesis as a microscopic theory of the {O}rsted magnetic field induction
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Sherif Abdulkader Tawfik
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A wire that conducts an electric current will give rise to circular magnetic field (the {O}rsted magnetic field) that is easily calculated using the Maxwell-Ampere equation. For wires with diameters in the macroscopic scale, this is an established physical law that has been demonstrated for two centuries. The Maxwell-Ampere equation is based on the argument that the induction of {O}rsted magnetic field is only a result of the displacement of charge. An alternative derivation of the {O}rsted magnetic field in conductors was suggested in [J. Mag. Mag. Mat. 504, 166660 (2020)] (will be called the current magnetization hypothesis (CMH) thereupon), which proposes that the {O}rsted magnetic field results from a two-body interaction. The present work establishes computationally, using simplified wire models, that the CMH reproduces the results of the Maxwell-Ampere equation for wires with a square cross section. Thus, CMH is proposed as a microscopic theory of magnetic induction, in contrast to the Maxwellian continuum theory of magnetic induction. I demonstrate that CMH could resolve the apparent contradiction between the observed induced magnetic field and that predicted by the Maxwell-Ampere equation in nanowires, as was reported in [Phys. Rev. B 99, 014436 (2019)]. The CMH shows that a possible reason for such contradiction is the presence of non-conductive surface layers in conductors.
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