Energy Stored in Charged Capacitor: Kaluza-Klein Theory

[Spinnor]

In terms of Kaluza-Klein theory how does one view the stored electromagnetic energy between the plates of a charged capacitor.

Thanks!

 

[PeterDonis]

I'm not sure what you're asking. Kaluza-Klein theory is equivalent to the Einstein Field Equation + Maxwell's Equations. So it includes standard electrodynamics, which can explain the stored energy in a capacitor, and Kaluza-Klein theory would just use that same explanation.

 

[Spinnor]

In Kaluza_Klein charge can be thought of as momentum in the 5th dimension?

I guess I was looking for some kind of geometrical interpretation of electrostatic energy.

 

[PeterDonis]

In Kaluza_Klein charge can be thought of as momentum in the 5th dimension?

Sort of, yes; charge relates to how fast a particle is going around the small circle that is the 5th dimension. But I don't know how (or if) that interpretation can be extended to cover the energy stored in the field. In standard (4-dimensional) GR there is no way to define a localized "energy in the gravitational field" as a geometric object, and in Kaluza-Klein theory what we call "electromagnetic" energy would be a form of "energy stored in the gravitational field" (interpreting "gravitational field" as the underlying 5-dimensional geometry).