The electric current is vector current
Frederick Guthrie say in 1873, that a positively loaded electroscope
is discharged, when close to it is brought a heated metal piece, linked to earth.
But, discharge did not occur, if the electroscope is charged negatively.
The experiment shows that earth has negative electric polarity.
Why does earth have negative polarity?
The electric potential of the earth, has as reference level the terrestrial surface.
The logic of such reference level is that we, the beings, exist here.
Increasing the altitude, the potential grows positively.
In depth to the center of the earth, the potential grows negatively.
At the thermometer, the reference level is zero,
above zero the temperature grows positively, below zero the temperature grows negatively.
Who and how is electric potential of earth produced?
Centripetal vectorial interaction is propagating by penetrating the substance towards the center of the earth,
with light speed and a accelerates with vectorially polarization (electric).
The polarities of substance on the direction of centripetal interaction propagation,
is the electric potential of the earth.
The table of the vector elements
Two vectors (vectorial currents) are surrounded orthogonally one another, making a double tor oscillator - atom of hydrogen or nucleon.
Hydrogen has stability, orthogonal symmetry and is the first element of the table.
The two vectorial currents are the known electric and magnetic fields.
Vectorial current connects nucleons amongst them,
adding step by step new elements in the table.
The symmetry and stability of the first element
is changed by each and every added nucleon, up to the time elements become unstable, radioactive.
Such modifications determine the properties of elements.
Vectorial current
Vectorial current is the closure of the two orthogonal orientations (electric and magnetic)
The property of semiconductor to set or not vectorial current by PN junction,
comes from the symmetry of vectorial currents.
Some atoms are missing orthogonal symmetry of vectorial currents.
Therefore, their polarity is not induced to neighboring atoms, in order to make vectorial current.
The abundance of radiations also contribute to the lack of symmetry (photons, temperature)
At the opposite "pole", electric and magnetic superconductivity is found.
Vectorial junction PN

The junction of P and N structures make a capacity, with the two electrostatically loaded structures.
The polarities of junction, the field lines, are electrostatically unified.
Direct supply, closes vectorial currents by all the polarities of the junction and
launches centripetal interaction, by setting a current bridge- (electric arc)
Obviously, the arc can be performed with pure metal junctions as well, supplied in DC and AC
Inverse supply, commutes polarities which are not inversed on the new polarities, opposed now, and
generates eddy currents, which interrupt vectorial current amongst structures (the bridge is down).