In this paper, we always assume that H is an N-dimensional complex Hilbert space. Let L(H) be the set of all linear operators from H to H . A state ρ of some quantum system, described by H , is a positive semi-definite operator of trace one, in particular, for each unit vector |ψ〉 ∈ H , the operator ρ = |ψ〉〈ψ| is said to be a pure state. The set of all states onH is denoted by D(H). If X,Y ∈ L(...

in this paper we give conditions for a tuple of commutative bounded linear operators which holds in the property of the hypercyclicity criterion. we characterize topological transitivity and semi-hereiditarily of a dynamical system given  by an n-tuple of operators acting on a separable infinite dimensional banach space .

If T and S are quasisimilar bounded operators on Banach spaces, we prove that each closed-and-open subset of the lower semiBrowder essential spectrum of T intersects one special part of the upper semi-Browder essential spectra of T and S. AMS Mathematics Subject Classification (1991): 47A53, 47A10

in this paper‎, ‎we show the stability of gustafson‎, ‎weidmann‎, ‎kato‎, ‎wolf‎, ‎schechter and browder essential spectrum of bounded linear operators on banach spaces which remain invariant under additive perturbations‎ ‎belonging to a broad classes of operators $u$ such $gamma(u^m)

SUOWA operators are a new family of aggregation functions that simultaneously generalize weighted means and OWA operators. Semi-uninorms, which are an extension of uninorms by dispensing with the symmetry and associativity properties, play a fundamental role in their definition. In this paper we show several procedures to construct semi-uninorms. The first one allows us to obtain continuous sem...

For a generator A of a C0 -semigroup T (·) on a Banach space X we consider the semi-norm Mk x := lim supt→0+ ‖t−1(T (t)− I)Ak−1x‖ on the Favard space Fk of order k associated with A . The use of this semi-norm is motivated by the functional analytic treatment of time-discretization methods of linear evolution equations. We show that sharp inequalities for bounded linear operators on D(Ak) can b...