RANK-PRESERVING LINEAR MAPS ON B(X)

Denote by B(X) the Banach algebra of all bounded linear operators on a complex Banach space X. In this paper, the representation of weakly continuous linear maps on B(X) which maps rank-1 operators to operators of rank at most 1 is given, and sequentially, some representation theorems for rank-preserving linear maps, spectrum-preserving linear maps and positivity-preserving linear maps on B(X) are obtained.