Extensions of interpolation between the arithmetic-geometric mean inequality for matrices

Abstract In this paper, we present some extensions of interpolation between the arithmetic-geometric means inequality. Among other inequalities, it is shown that if A, B, X are n × n $n\times n$ matrices, then ∥ A X B ∗ ∥ 2 ≤ ∥ f 1 ( A ∗ A ) X g 1 ( B ∗ B ) ∥ ∥ f 2 ( A ∗ A ) X g 2 ( B ∗ B ) ∥ , $$\b...

Full description

Bibliographic Details
Main Authors: Mojtaba Bakherad, Rahmatollah Lashkaripour, Monire Hajmohamadi
Format: Article
Language:English
Published: SpringerOpen 2017-09-01
Series:Journal of Inequalities and Applications
Subjects:
Online Access:http://link.springer.com/article/10.1186/s13660-017-1485-x
_version_ 1828390245591154688
author Mojtaba Bakherad
Rahmatollah Lashkaripour
Monire Hajmohamadi
author_facet Mojtaba Bakherad
Rahmatollah Lashkaripour
Monire Hajmohamadi
author_sort Mojtaba Bakherad
collection DOAJ
description Abstract In this paper, we present some extensions of interpolation between the arithmetic-geometric means inequality. Among other inequalities, it is shown that if A, B, X are n × n $n\times n$ matrices, then ∥ A X B ∗ ∥ 2 ≤ ∥ f 1 ( A ∗ A ) X g 1 ( B ∗ B ) ∥ ∥ f 2 ( A ∗ A ) X g 2 ( B ∗ B ) ∥ , $$\begin{aligned} \bigl\Vert AXB^{*} \bigr\Vert ^{2}\leq \bigl\Vert f_{1} \bigl(A^{*}A\bigr)Xg_{1}\bigl(B^{*}B\bigr) \bigr\Vert \bigl\Vert f_{2}\bigl(A^{*}A\bigr)Xg_{2}\bigl(B^{*}B\bigr) \bigr\Vert , \end{aligned}$$ where f 1 $f_{1}$ , f 2 $f_{2}$ , g 1 $g_{1}$ , g 2 $g_{2}$ are non-negative continuous functions such that f 1 ( t ) f 2 ( t ) = t $f_{1}(t)f_{2}(t)=t$ and g 1 ( t ) g 2 ( t ) = t $g_{1}(t)g_{2}(t)=t$ ( t ≥ 0 $t\geq0$ ). We also obtain the inequality | | | A B ∗ | | | 2 ≤ | | | p ( A ∗ A ) m p + ( 1 − p ) ( B ∗ B ) s 1 − p | | | | | | ( 1 − p ) ( A ∗ A ) n 1 − p + p ( B ∗ B ) t p | | | , $$\begin{aligned} \bigl\vert \!\bigl\vert \!\bigl\vert AB^{*} \bigr\vert \!\bigr\vert \!\bigr\vert ^{2} &\leq \bigl\vert \!\bigl\vert \!\bigl\vert p \bigl(A^{*}A\bigr)^{\frac{m}{p}}+ (1-p) \bigl(B^{*}B\bigr)^{\frac {s}{1-p}} \bigr\vert \!\bigr\vert \!\bigr\vert \bigl\vert \!\bigl\vert \!\bigl\vert (1-p) \bigl(A^{*}A\bigr)^{\frac{n}{1-p}}+ p\bigl(B^{*}B \bigr)^{\frac{t}{p}} \bigr\vert \!\bigr\vert \!\bigr\vert , \end{aligned}$$ in which m, n, s, t are real numbers such that m + n = s + t = 1 $m+n=s+t=1$ , | | | ⋅ | | | $\vert \!\vert \!\vert \cdot \vert \!\vert \!\vert $ is an arbitrary unitarily invariant norm and p ∈ [ 0 , 1 ] $p\in[0,1]$ .
first_indexed 2024-12-10T06:40:47Z
format Article
id doaj.art-ec8c775a43c04023b1c30d7c86e2abb3
institution Directory Open Access Journal
issn 1029-242X
language English
last_indexed 2024-12-10T06:40:47Z
publishDate 2017-09-01
publisher SpringerOpen
record_format Article
series Journal of Inequalities and Applications
spelling doaj.art-ec8c775a43c04023b1c30d7c86e2abb32022-12-22T01:58:47ZengSpringerOpenJournal of Inequalities and Applications1029-242X2017-09-012017111010.1186/s13660-017-1485-xExtensions of interpolation between the arithmetic-geometric mean inequality for matricesMojtaba Bakherad0Rahmatollah Lashkaripour1Monire Hajmohamadi2Department of Mathematics, Faculty of Mathematics, University of Sistan and BaluchestanDepartment of Mathematics, Faculty of Mathematics, University of Sistan and BaluchestanDepartment of Mathematics, Faculty of Mathematics, University of Sistan and BaluchestanAbstract In this paper, we present some extensions of interpolation between the arithmetic-geometric means inequality. Among other inequalities, it is shown that if A, B, X are n × n $n\times n$ matrices, then ∥ A X B ∗ ∥ 2 ≤ ∥ f 1 ( A ∗ A ) X g 1 ( B ∗ B ) ∥ ∥ f 2 ( A ∗ A ) X g 2 ( B ∗ B ) ∥ , $$\begin{aligned} \bigl\Vert AXB^{*} \bigr\Vert ^{2}\leq \bigl\Vert f_{1} \bigl(A^{*}A\bigr)Xg_{1}\bigl(B^{*}B\bigr) \bigr\Vert \bigl\Vert f_{2}\bigl(A^{*}A\bigr)Xg_{2}\bigl(B^{*}B\bigr) \bigr\Vert , \end{aligned}$$ where f 1 $f_{1}$ , f 2 $f_{2}$ , g 1 $g_{1}$ , g 2 $g_{2}$ are non-negative continuous functions such that f 1 ( t ) f 2 ( t ) = t $f_{1}(t)f_{2}(t)=t$ and g 1 ( t ) g 2 ( t ) = t $g_{1}(t)g_{2}(t)=t$ ( t ≥ 0 $t\geq0$ ). We also obtain the inequality | | | A B ∗ | | | 2 ≤ | | | p ( A ∗ A ) m p + ( 1 − p ) ( B ∗ B ) s 1 − p | | | | | | ( 1 − p ) ( A ∗ A ) n 1 − p + p ( B ∗ B ) t p | | | , $$\begin{aligned} \bigl\vert \!\bigl\vert \!\bigl\vert AB^{*} \bigr\vert \!\bigr\vert \!\bigr\vert ^{2} &\leq \bigl\vert \!\bigl\vert \!\bigl\vert p \bigl(A^{*}A\bigr)^{\frac{m}{p}}+ (1-p) \bigl(B^{*}B\bigr)^{\frac {s}{1-p}} \bigr\vert \!\bigr\vert \!\bigr\vert \bigl\vert \!\bigl\vert \!\bigl\vert (1-p) \bigl(A^{*}A\bigr)^{\frac{n}{1-p}}+ p\bigl(B^{*}B \bigr)^{\frac{t}{p}} \bigr\vert \!\bigr\vert \!\bigr\vert , \end{aligned}$$ in which m, n, s, t are real numbers such that m + n = s + t = 1 $m+n=s+t=1$ , | | | ⋅ | | | $\vert \!\vert \!\vert \cdot \vert \!\vert \!\vert $ is an arbitrary unitarily invariant norm and p ∈ [ 0 , 1 ] $p\in[0,1]$ .http://link.springer.com/article/10.1186/s13660-017-1485-xarithmetic-geometric meanunitarily invariant normHilbert-Schmidt normCauchy-Schwarz inequality
spellingShingle Mojtaba Bakherad
Rahmatollah Lashkaripour
Monire Hajmohamadi
Extensions of interpolation between the arithmetic-geometric mean inequality for matrices
Journal of Inequalities and Applications
arithmetic-geometric mean
unitarily invariant norm
Hilbert-Schmidt norm
Cauchy-Schwarz inequality
title Extensions of interpolation between the arithmetic-geometric mean inequality for matrices
title_full Extensions of interpolation between the arithmetic-geometric mean inequality for matrices
title_fullStr Extensions of interpolation between the arithmetic-geometric mean inequality for matrices
title_full_unstemmed Extensions of interpolation between the arithmetic-geometric mean inequality for matrices
title_short Extensions of interpolation between the arithmetic-geometric mean inequality for matrices
title_sort extensions of interpolation between the arithmetic geometric mean inequality for matrices
topic arithmetic-geometric mean
unitarily invariant norm
Hilbert-Schmidt norm
Cauchy-Schwarz inequality
url http://link.springer.com/article/10.1186/s13660-017-1485-x
work_keys_str_mv AT mojtababakherad extensionsofinterpolationbetweenthearithmeticgeometricmeaninequalityformatrices
AT rahmatollahlashkaripour extensionsofinterpolationbetweenthearithmeticgeometricmeaninequalityformatrices
AT monirehajmohamadi extensionsofinterpolationbetweenthearithmeticgeometricmeaninequalityformatrices