Time: 21. November 2008
Place: Institute of Physics
Title: Interpretation of Kalb-Ramond Field in Riemann-Cartan Geometries
We give two different geometric interpretation of the Kalb-Ramond field of bosonic string theory. Given the generalized Papapetrou method for derivation of equations of motion for a p-brane in Riemann-Cartan spacetimes, we derive appropriate equations of motion. Comparing them with the equations postulated in string theory, we read off the dependence of the Kalb-Ramond field on the spacetime torsion and the spin of the string. The first interpretation relates the Kalb-Ramond field to the appropriate component of the contorsion tensor in a special geometry where contorsion tensor is factored into two parts. The second interpretation relates it to one of the extra components of contorsion coming from the compact extra dimension in a simple Kaluca-Klein model. We also demonstrate that it is not possible to interpret the Kalb-Ramond field as the potential for torsion in Riemann-Cartan geometries.