On the continuity of harmonic mappings and the Boundary.
A field of three-component unit vectors on the dimensional spacetime is considered. Two field configurations with different values of the topological charge cannot be connected by the path of field configurations with a finite Euclidean action. Therefore there is no transition between them. The initial and final configurations are assumed to be continuous at infinity. The asymptotic behaviour of intermediate configurations may be arbitrary. The proof is based on the properties of the degree of...
Si studiano le applicazioni -tangenti da a date come estensioni omogenee di -forme armoniche. Vengono ricavate condizioni necessarie sul grado affinche tali applicazioni -tangenti siano di energia minima. Una classificazione completa viene data nel caso in cui tali applicazioni tangenti di energia minima vadano da su .