The structure of projected center vortices at zero and finite temperature

We investigate the structure of center projected vortices of SU(2) lattice gauge theory at zero and finite temperature. At zero temperature we find, i n agreement with the area law behaviour of Wilson loops, that most of the P -vortex plaquettes are parts of a single huge vortex. This vortex is an uno rientable surface and has a very irregular structure with many handles. Sma ll P-vortices, and short-range fluctuations of the large vortex surface, do not contribute to the string tension. At finite temperature P-vortices exi st also in the deconfined phase. However, they form cylindric objects which extend in time direction and consist only of space-space plaquettes.