When r=0 in Coulomb's law; electron self-repulsion

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Discussion Overview

The discussion revolves around the implications of Coulomb's law when considering an electron's self-repulsion at a distance of zero (r=0). Participants explore the nature of the electron as a point particle and the resulting challenges in understanding the infinite force that would arise from self-repulsion.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants note that the electrostatic force is inversely proportional to r², leading to potential issues when r=0.
  • One participant suggests that the electron must not be considered a classical point particle to resolve the issue of infinite force.
  • Another participant references Fermilab, indicating that while the electron is described as a point particle, the solution may involve concepts like quantum foam.
  • It is proposed that even if the electron is treated as a classical point particle, there is no force acting on it from its own potential, as the total potential energy does not depend on its position.
  • A later reply acknowledges the perspective of potential energy as a valid approach to understanding the situation.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the electron and the implications of treating it as a point particle. There is no consensus on how to resolve the issue of self-repulsion at r=0.

Contextual Notes

Participants highlight the limitations of classical interpretations and the potential need for quantum mechanical considerations. The discussion remains open regarding the definitions and implications of the electron's properties.

nomadreid
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Given that
(a) the electrostatic force is inversely proportional to r2
(b) that the electron is (when it is determined) a point
(c) that the repulsion for an electron to itself is therefore r=0
(d) that r=0 would naively end up with infinite force
What is the way out of this problem?
Thanks
 
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The electron must not be a classical point particle.
 
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Even when viewing the electron as a classical point particle, there is no force acting on it from its own potential. The total potential energy (although technically infinite) does not depend on where the electron is located and the force is given by how the total potential depends on the position.
 
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Orodruin: Ah, looking at it from the point of view of potential energy... that makes sense, thanks.
 

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