Author/Authors :
Takayuki Furuta، نويسنده , , Mariko Giga، نويسنده ,
Abstract :
We shall discuss operator inequalities which are obtained by elementary lemma (Lemma 3.1), associated with Hölder–McCarthy and Kantorovich inequalities. Firstly we shall give the following complementary result to Mi i et al. [Linear Algebra Appl., 360 (2003) 15].
Let A and B be two strictly positive operators on a Hilbert space H such that M1I A m1I>0 and M2I B m2I>0, where M1>m1>0, M2>m2>0 and A B.
(a) If p>1 and q>1, then the following inequality holds: (b) If p<0 and q<0, then the following inequality holds:
We remark that (a) is shown in [Linear Algebra Appl., 360 (2003) 15] as an extension of two variable version of our previous one variable one [J. Inequal. Appl. 2 (1998) 137]. Secondly, we shall show the following extension of two parameters type of an extension of Fujii et al. [Sci. Math. 1 (1998) 307] on the determinant of an operator.
Let T be strictly positive operators on a Hilbert space H such that MI T mI>0. Then the following inequality holds: Sh(p,q)Δx(Tq) (Tpx,x) Δx(Tp) for p>0 and q>0,whereSh(p,q) is defined by andthe determinant Δx(T) for strictly positive operator T at a unit vector x in Hilbert space H is defined by Δx(T)=exp ((logT)x,x) .
As an application of this result, we shall give an alternative proof of two variable version of characterization of the chaotic order in [Linear Algebra Appl. ibid., Theorem 4.4].