Connections on embedded manifolds.
Geometric constructions of connections on the higher order principal prolongations of a principal bundle are considered. Moreover, the existing differences among connections on non-holonomic, semiholonomic and holonomic principal prolongations are discussed.
We discuss the problem of prescribing the curvature of a connection on a principal bundle whose base manifold is three-dimensional. In particular, we consider the local question: Given a curvature form , when does there exist locally a connection such that is the curvature of ? When the structure group of the bundle is semisimple, a finite number of nonlinear identities arise as necessary conditions for local solvability of the curvature equation. We conjecture that these conditions are also...
I vari metodi di definire connessioni adattate ad un Riferimento fisico vengono qui ricondotti ad un unico formalismo. Viene inoltre introdotta la nozione generale di campo gravitazionale affine adattato (sia al Riferimento che alla connessione).