- #1

rumborak

- 706

- 154

In the thread about EM waves, the EM wave equation

[tex] \left(c^2\nabla^2 - \frac{\partial^2}{\partial t^2} \right) E = 0 [/tex]

got me pondering. The term

[tex] \frac{\partial^2}{\partial t^2} E [/tex]

is the second derivative of the field. In a solid-body wave equation, that same term (not with E, but the physical displacement instead) essentially comes down to the inertia of the local particle, through F=ma, a being the second derivative of displacement.

So, the pondering is: How come the EM field is able to work on this second-derivative level as well? Does the EM field have a sort of "inertia" (and even "speed" as the first derivative), just like mass does? Are those two connected on a fundamental level, e.g. "any property of spacetime can have acceleration-dependent effects"?

I hope this thought doesn't come across as too crazy :)

[tex] \left(c^2\nabla^2 - \frac{\partial^2}{\partial t^2} \right) E = 0 [/tex]

got me pondering. The term

[tex] \frac{\partial^2}{\partial t^2} E [/tex]

is the second derivative of the field. In a solid-body wave equation, that same term (not with E, but the physical displacement instead) essentially comes down to the inertia of the local particle, through F=ma, a being the second derivative of displacement.

So, the pondering is: How come the EM field is able to work on this second-derivative level as well? Does the EM field have a sort of "inertia" (and even "speed" as the first derivative), just like mass does? Are those two connected on a fundamental level, e.g. "any property of spacetime can have acceleration-dependent effects"?

I hope this thought doesn't come across as too crazy :)

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