The simple center projection of SU(2) gauge theory

We consider the SU(2) lattice gauge model. We propose a new gauge invariant definition of center projection, which we call the Simple Center Projectio n. We demonstrate the center dominance, i.e., the coincidence of the projec ted potential with the full potential up to the mass renormalization term a t low energies. We also consider the center vortices and the center monopol es (nexuses). It turns out that the behavior of such objects qualitatively coincides with the behavior of the vortices and monopoles in the Maximal Ce nter gauge. The connection of the condensation of nexuses with the dual sup erconductor theory is discussed. Numerically the procedure of extracting th e center vortices proposed in this Letter is much simpler than the usual Ma ximal Center Projection. (C) 2001 Published by Elsevier Science B.V.