Equivalence of Euler equations and torque-angular momentum relation

Equations of Motion of Systems with Internal Angular Momentum

The angular momentum of a many-particle system with respect to its centre of mass is known as the ”internal angular momentum” and is a property of the system that is independent of the observer. Internal angular momentum is therefore and attribute that characterizes a system in the same way as its mass or charge. In the case of a rigid body and particularly in the case of an elementary particle...

Evolution equations for higher moments of angular momentum distributions

Based on a sumrule for the nucleon spin we expand quark and gluon orbital angular momentum operators and derive an evolution matrix for higher moments of the corresponding distributions. In combination with the spindependent DGLAP-matrix we find a complete set of spin and orbital angular momentum evolution equations.

Consistency in formulation of spin current and torque associated with a variance of angular momentum.

Based on the Noether's theorem, we develop systematically and rigorously the spin-dependent formulation of the conservation laws. The effect of the electronic polarization due to the spin-orbit coupling is included in the Maxwell equations. The polarization is related to the antisymmetric components of spin current, and it provides a possibility to measure the spin current directly. The varianc...

Angular Momentum

Rotations and Angular Momentum

2 Exercise. Prove it. ◦ In fact, as sophisticates can show you, on a complex space a linear operator which preserves all norms will also preserve all inner products. But the key thing is to remember is that a unitary operator preserves all inner products (and therefore all norms). • This is analogous to the fact that translations and rotations in ordinary three-dimensional space preserve distan...