Frontiers of Physics

, 12:128503 | Cite as

Spin in the extended electron model

  • Thomas Pope
  • Werner Hofer
Research article


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.


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



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


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Copyright information

© Higher Education Press and Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.School of ChemistryNewcastle UniversityNewcastleUK

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