Maps Preserving Numerical Radius or Cross Norms of Products of Self-adjoint Matrics on 2×2 Matrix Space
Xiuling Zhang · Journal of Shanxi Normal University · 2010
The unital surjective maps on 2×2 self-adjoint matix space which preserving the numerical radius of product or Jordan semi-product of self-adjoint matrices or preserving a cross norm of products or Jordan semi-products of self-adjoint matrices are characterized.These supplement the corresponding results for n×n self-adjoint matrix space with n≥3.