Kalusa-Klein approach in higher-dimensional theories of gravity with torsion

The Kaluza-Klein approach is investigated in the Einstein-Cartan-Sciama-Kibble (ECSK) theory and in a Brans-Dicke-type model with torsion. In particular, the authors focus their attention on the possible coupling of gauge fields and torsion, the principle of minimal coupling and the possible physical meaning of the fields which originate from the higher-dimensional torsion fields. Also, it is known that Brans-Dicke-type models with torsion have an extended conformal symmetry. They investigate the fate of this symmetry when going (via dimensional reduction) to four dimensions. They find that the vectorial part of the torsion acquires a nonvanishing value, thus breaking the symmetry of the original five-dimensional theory.