On an Extended System of Relativistic Kinematical Quantities Some Applications in Magnetohydrodynamics

Ilija Lukačević

We consider two vector fields forming trajectories in the general relativistic spacetime. The first one is a field of four velocities whereas the second one is a field of spacelike vectors of variable intensity. Kinematical parameters, expansion, shear and rotation are formed with respect to both fields and called extended kinematical quantities for the second one. Then applications are made to MHD in order to obtain some basic formulae symmetric to already known ones.