This paper concerns fixed point
theorems for nonexpansive mappings in conjugate Banach spaces. An example shows
that there exist fixed-point-free affine isometries on weak∗ compact convex sets.
Asymptotic centers of decreasing net of founded sets in l1 are shown to be compact
and a common fixed point theorem for left reversible topological semigroup of
nonexpansive mappings in l1 is given.