Declare 1-forms
ej and
uk for corresponding coframes:
Declare abstract mapping between the sphere and the plane:
Declare definite mapping between the sphere and the plane:
Declare another definite mapping between the sphere and the plane:
One can calculate pullback of any [0,k] tensor field under a mapping (see
Pullback):
pullback of exterior product d(

)

d(

) under mapping

:
pullback of "rotation" 1-form under mapping psi:
pullback of "rotation" 1-form under mapping

:
pullback of exterior product Wedge[d[x], d[y]] under abstract mapping

: