We present a weak majorization inequality and apply it to prove eigenvalue and unitarily invariant norm extensions of a version of the Bohrs inequality due to Vasic and Kev{c}kic.
We survey several significant results on the Bohr inequality and presented its generalizations in some new approaches. These are some Bohr type inequalities of Hilbert space operators related to the matrix order and the Jensen inequality. An eigenval
ue extension of Bohrs inequality is discussed as well.
Yuan and Leng (2007) gave a generalization of Ky Fans determinantal inequality, which is a celebrated refinement of the fundamental Brunn-Minkowski inequality $(det (A+B))^{1/n} ge (det A)^{1/n} +(det B)^{1/n}$, where $A$ and $B$ are positive semidef
inite matrices. In this note, we first give an extension of Yuan-Lengs result to multiple positive definite matrices, and then we further extend the result to a larger class of matrices whose numerical ranges are contained in a sector. Our result improves a recent result of Liu [Linear Algebra Appl. 508 (2016) 206--213].
We present some new inequalities related to determinant and trace for positive semidefinite block matrices by using symmetric tensor product, which are extensions of Fiedler-Markhams inequality and Thompsons inequality.
We compute the deficiency spaces of operators of the form $H_A{hat{otimes}} I + I{hat{otimes}} H_B$, for symmetric $H_A$ and self-adjoint $H_B$. This enables us to construct self-adjoint extensions (if they exist) by means of von Neumanns theory. The
structure of the deficiency spaces for this case was asserted already by Ibort, Marmo and Perez-Pardo, but only proven under the restriction of $H_B$ having discrete, non-degenerate spectrum.
In this article, we explore the celebrated Gr{u}ss inequality, where we present a new approach using the Gr{u}ss inequality to obtain new refinements of operator means inequalities. We also present several operator Gr{u}ss-type inequalities with applications to the numerical radius and entropies.