A singular value inequality for sums and products of Hilbert space operators is given. This inequality generalizes several recent singular value inequalities, and includes that if A, B, and X are positive operators on a complex Hilbert space H, then sj ( A 1/2 XB 1/2 ) ≤ 1 2 ‖X‖ sj (A+B) , j = 1, 2, · · · , which is equivalent to sj ( A 1/2 XA 1/2 −B 1/2 XB 1/2 ) ≤ ‖X‖ sj (A⊕B) , j = 1, 2, · · ...

Among all linear operators on Hilbert spaces, the compact ones (defined below) are the simplest, and most closely imitate finite-dimensional operator theory. In addition, compact operators are important in practice. We prove a spectral theorem for self-adjoint compact operators, which does not use broader discussions of properties of spectra, only using the Cauchy-Schwarz-Bunyakowsky inequality...

In this talk, matrix inequality characterizations for the positive realness of descriptor systems are introduced. Hence, the celebrated positive real lemma for standard state space systems is established for descriptor systems. In addition, the lossless positive realness of both standard state space systems and descriptor systems are characterized explicitly based on the controllable staircase ...

Please do not cite without permission The concept of 'tradition' is used in a range of different ways within studies of British politics. Despite this there have been only a few attempts to theorise notions of tradition within British political science. Furthermore the different concepts of tradition forwarded by conservatives, interpretivists and realists have each been contested. This paper e...

Some new reverses of the Cauchy-Bunyakovsky-Schwarz integral inequality for vector-valued functions in Hilbert spaces that complement the recent results obtained in [1] are given. Applications for the Heisenberg inequality are provided.

We find the largest ǫ for which any simple closed path α in the universal cover R̃2 \ Z2 of R2 \ Z2, equipped with the natural lifted metric from the Euclidean two dimensional plane, satisfies L(α) ≥ ǫA(α). Where L(α) is the length of α and A(α) is the area enclosed by α. This generalizes a result of Schnell and Gomis, and provides an alternative proof for the same isoperimetric inequality in R2...

X iv :m at h/ 04 06 10 8v 1 [ m at h. FA ] 6 J un 2 00 4 QUADRATIC REVERSES OF THE CONTINUOUS TRIANGLE INEQUALITY FOR BOCHNER INTEGRAL OF VECTOR-VALUED FUNCTIONS IN HILBERT SPACES SEVER S. DRAGOMIR Abstract. Some quadratic reverses of the continuous triangle inequality for Bochner integral of vector-valued functions in Hilbert spaces are given. Applications for complex-valued functions are prov...

The Hooman{Wielandt inequality which gives a bound for the distance between the spectra of two normal matrices, is generalized to normal operators A; B on a separable Hilbert space, such that A ? B is Hilbert{Schmidt.

In this paper we consider the order-like relation for self-adjoint operators on some Hilbert space. This relation is defined by using Jensen inequality. We will show that under some assumptions this relation is antisymmetric.

Among all linear operators on Hilbert spaces, the compact ones (defined below) are the simplest, and most closely imitate finite-dimensional operator theory. In addition, compact operators are important in practice. We prove a spectral theorem for self-adjoint compact operators, which does not use broader discussions of properties of spectra, only using the Cauchy-Schwarz-Bunyakowsky inequality...