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

In summary, the conversation discusses the problem of infinite force when considering the electron as a classical point particle. However, the solution lies in understanding the electron as a point particle in the quantum foam, and from the perspective of potential energy rather than classical mechanics.
  • #1
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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  • #2
The electron must not be a classical point particle.
 
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  • #3
DaleSpam said:
The electron must not be a classical point particle.
OK, that "classical" in the answer is perhaps the key. But it is, according to Fermilab, http://www.fnal.gov/pub/today/archive/archive_2013/today13-02-15_NutshellReadMore.html, a point particle, even if not classical. That site hints that the solution lies in the quantum foam, but it isn't very explicit in its explanation.
 
  • #4
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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  • #5
Orodruin: Ah, looking at it from the point of view of potential energy... that makes sense, thanks.
 

1. What is Coulomb's law?

Coulomb's law is a fundamental law of physics that describes the electrostatic interaction between two point charges. It states that the force between two charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.

2. What does r=0 mean in Coulomb's law?

In Coulomb's law, r represents the distance between the two charges. When r=0, it means that the two charges are located at the same point in space, resulting in an infinite force between them.

3. Why does electron self-repulsion occur when r=0 in Coulomb's law?

Electron self-repulsion occurs when r=0 in Coulomb's law because electrons are negatively charged particles. When two electrons are located at the same point in space, the force between them becomes infinite due to the repulsive nature of like charges.

4. How does the value of r affect the force between charges in Coulomb's law?

The value of r has a significant impact on the force between charges in Coulomb's law. As r increases, the force decreases, and as r decreases, the force increases. When r=0, the force becomes infinite, as described by the inverse square relationship in the law.

5. Can Coulomb's law be applied to all charged particles?

Yes, Coulomb's law can be applied to all charged particles, regardless of their nature or size. It is a fundamental law of electrostatics that governs the behavior of charged particles in any system.

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