I believe it's not a matter of "noise". Rather, metals and plasma are conductive up to a certain frequency. Beyond that frequency, resistance goes up and the ma

I believe it's not a matter of "noise". Rather, metals and plasma are conductive up to a certain frequency. Beyond that frequency, resistance goes up and the material becomes transparent. This is basically because the electrons can't "keep up" with the electric field's oscillation so they are ineffective at screening it.