Past exam of the mathematics course of the University of Cambridge 2014 iii Paper 50 1 b ii Solution Created 2026-10-03 Updated 2026-10-06
A type covariant tensor is a multilinear form on vectors. For arbitrary , the pullback of a covariant tensor isProjection of all covariant slots means . Since every pushed-forward vector is already tangential,Equality on all arguments proves . No antisymmetry is needed: this holds for every covariant tensor, not only for differential forms.
Pullback of a covariant tensor 2026-10-06
The pullback of a covariant tensor composes each of its vector arguments with the differential of a smooth map. It takes a type tensor on the target to one on the source. Antisymmetry is not required; the pullback of a differential form is the alternating special case. If the target vectors are projected onto the image tangent space first, evaluating the pullback is unchanged.