Can Point Particles Have Infinite Energy in Fields?

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SUMMARY

The discussion centers on the concept of infinite energy in the electric field of point particles, specifically addressing the paradox of infinite energy density at the r = 0 limit. It concludes that while classical electromagnetism (E&M) suggests infinite energy, Quantum Electrodynamics (QED) provides a framework for understanding this phenomenon through virtual particle interactions. The 1/r potential remains valid outside the charged body, and the assumption of finite particle size is crucial to resolving the paradox without invoking space-time singularities.

PREREQUISITES
  • Understanding of classical electromagnetism (E&M)
  • Familiarity with Quantum Electrodynamics (QED)
  • Knowledge of the concept of virtual particles
  • Basic grasp of the Standard Model of particle physics
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  • Study the implications of Quantum Electrodynamics on classical physics
  • Research the role of virtual particle pairs in energy shielding
  • Explore the concept of finite particle size in quantum physics
  • Investigate the relationship between point particles and space-time singularities
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Physicists, students of theoretical physics, and anyone interested in the implications of quantum mechanics on classical theories, particularly in the context of energy in electric and gravitational fields.

urnchurl
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When finding the amount of energy stored in the electric field of a point particle, one finds that it is infinite (due to the r = 0 limit in the integral of the energy density). Does this mean then that the field will never "run out" of energy?

How can the electric field of a point charge, or the gravitational field of a point mass contain an infinite amount of energy without resulting in a space-time singularity (if one considers a finite volume containing the point mass or charge)?

Thanks.
 
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It would mean that the field contained an infinite amount of energy. This was a recognized problem in classical E&M and was not really solved until Quantum Electrodynamics was completed.

One way to think of the answer is that as the energy density increases for small r, you get more and more virtual e+/e- pairs, and they "shield" the charge at the center. At least, I think the argument goes something like that.
 
The 1/r potential is valid as long as you are outside the charged body.
It is reasonable to assume that even an electron has a finite size.
Below a certain scale, classical physics is not applicable anyway.
 
lalbatros said:
The 1/r potential is valid as long as you are outside the charged body.
It is reasonable to assume that even an electron has a finite size.
Below a certain scale, classical physics is not applicable anyway.

Doesn't the Standard Model comprehend point particles? That would seem to be particularly misleading.
 

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