Functional analysis
1. Some improvements of numerical radius inequalities via Specht’s ratio

Y. Khatib; M. Hassani

Volume 09, Issue 03 , Summer 2020, , Pages 221-230

Abstract
  We obtain some inequalities related to the powers of numerical radius inequalities of Hilbert space operators. Some results that employ the Hermite-Hadamard inequality for vectors in normed linear spaces are also obtained. We improve and generalize some inequalities with respect to ...  Read More

Functional analysis
2. The solutions to some operator equations in Hilbert $C^*$-module

M. Mohammadzadeh Karizaki; M. Hassani

Volume 04, Issue 01 , Winter 2015, , Pages 35-42

Abstract
  In this paper, we state some results on product of operators with closed ranges and we solve the operator equation $TXS^*-SX^*T^*= A$ in the general setting of the adjointable operators between Hilbert $C^*$-modules, when $TS = 1$. Furthermore, by using some block operator matrix techniques, ...  Read More

Functional analysis
3. On the superstability of a special derivation

M. Hassani; E. Keyhani

Volume 03, Issue 01 , Winter 2014, , Pages 15-22

Abstract
  The aim of this paper is to show that under some mild conditions a functional equation of multiplicative $(\alpha,\beta )$-derivation is superstable on standard operator algebras. Furthermore, we prove that this generalized derivation can be a continuous and an inner $(\alpha,\beta)$-derivation.  Read More