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Spin in the extended electron model


It has been found that a model of extended electrons is more suited to describe theoretical simulations and experimental results obtained via scanning tunnelling microscopes, but while the dynamic properties are easily incorporated, magnetic properties, and in particular electron spin properties pose a problem due to their conceived isotropy in the absence of measurement. The spin of an electron reacts with a magnetic field and thus has the properties of a vector. However, electron spin is also isotropic, suggesting that it does not have the properties of a vector. This central conflict in the description of an electron’s spin, we believe, is the root of many of the paradoxical properties measured and postulated for quantum spin particles. Exploiting a model in which the electron spin is described consistently in real three-dimensional space–an extended electron model–we demonstrate that spin may be described by a vector and still maintain its isotropy. In this framework, we re-evaluate the Stern–Gerlach experiments, the Einstein–Podolsky–Rosen experiments, and the effect of consecutive measurements and find in all cases a fairly intuitive explanation.

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The authors acknowledge EPSRC funding for the UKCP consortium, grant No. EP/K013610/1.

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Correspondence to Thomas Pope.

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Pope, T., Hofer, W. Spin in the extended electron model. Front. Phys. 12, 128503 (2017).

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  • spin
  • extended electron model
  • geometric algebra
  • Stern–Gerlach experiment
  • Einstein–Podolsky–Rosen
  • magnetism