Comments on noncommutative gauge theories

We study the gauge theories on noncommutative space. We employ the idea of the covariant position to understand the linear and angular momenta, the ce nter of mass position, and to express all gauge invariant observables inclu ding the Wilson line. In addition, we utilize the universality of the U(1) gauge theory, which originates from the underlying matrix theory, to analyz e various solitons on U(N) theories, like the unstable static vortex soluti ons in two dimensions and BPS dyonic fluxon solutions. (C) 2001 Published b y Elsevier Science B.V.