Recent content by Mordyn

One other subtlety on magnetic shielding... A material with zero resistance (i.e. a "perfect conductor") is not necessarily a superconductor. This is because while infinite conductivity allows a material to resist changes in magnetic field via induction, it is not necessarily sufficient to expel...

Yep, although I think we should be careful about the interpretation of electric "shielding." A conducting shell enclosing a point charge does not actually prevent the electric field from reappearing in full to the outside world at its outer boundary (it is only zero within the conductive...

I am aware. The point was to describe why the shielding effect fails (it is not simply that aluminum has no effect on magnetic fields), and to clarify what determines the timescale over which the field can penetrate it. The author should provide some numerical estimation of these quantities if...

The issue is the finite (non-zero) resistivity of essentially every conductor at non-cryogenic temperatures. Copper and other non-magnetic metals will actually provide an initial shielding response to a suddenly applied but otherwise constant magnetic field. The field will diffuse through it...

Yes, static magnetic fields can be locally deflected by either a containing boundary of magnetizable material (e.g. iron-based alloys) or by very highly conducting material surfaces. The circumstances of the study do not meet either of these conditions (the electrical conductivity of the metal...

This study is on very shaky theoretical ground. One major issue is the author doesn't seem to understand how atmospheric conductivity works. It is dominated in the ionosphere by the mobility of heavy atmospheric ions (H+, O+, etc.) and free electrons. Adding neutral (non-ionized) metals can...