Time: 17. July 2008
Place: Faculty of Physics
Title: Motion of extended objects in gravitational field with torsion
We consider the motion of extended objects in gravitational field with torsion. Using multipole formalism, from the assumptions of Poincaré invariance and localization of matter on some hypersurface, we derive equations of motion for a $p$-brane, along with appropriate boundary conditions. Then we analyze the most important cases of particle and string, thereby obtaining some interesting consequences. Namely, it turns out that the spin of Dirac particle does not couple to spacetime curvature, and furthermore can be neglected in single-pole approximation. Also, we considered one gross model of a meson which consists of a Nambu-Goto string with two particles attached to its ends. The model allows for the derivation of Regge trajecories with a correction due to internal angular momenta of the particles at the string ends.