文摘
Let A, B be n×nn×n positive definite matrices. Then for 0≤t≤10≤t≤1∏i=knλi(A∘B)≥∏i=knλi((A♯tB)(A♯1−tB))≥∏i=knλi(AB),k=1,…,n. This gives a weighted extension of a result of Ando [1]. The case where the eigenvalues λiλi are replaced with the singular values σiσi is also considered.