A survey of recent reverses for the generalised triangle inequality in inner product spaces
A theorem on isotropic spaces
Let X be a normed space and the group of all linear surjective isometries of X that are finite-dimensional perturbations of the identity. We prove that if acts transitively on the unit sphere then X must be an inner product space.
A triangle inequality for angles in a Hilbert space
A tutorial on conformal groups
Our concern is with the group of conformal transformations of a finite-dimensional real quadratic space of signature (p,q), that is one that is isomorphic to , the real vector space , furnished with the quadratic form , and especially with a description of this group that involves Clifford algebras.
Absolutely P-Summing, P-Nuclear Operators and Their Conjugates.
Accretive metric projections.
Algebraic theory of Atkinson operators
Almost surjective ε-isometries of Banach spaces
We investigate Hyers-Ulam stability of non-surjective ε-isomeries of Banach spaces. We also pose and discuss an open problem.
AMD-numbers, compactness, strict singularity and the essential spectrum of operators.
An algebraic characterization of complete inner product spaces.
An embedding theorem for Hilbert categories.
An identity in real inner product spaces.
An inequality for bi-orthogonal pairs.
An infinite-dimensional pre-Hilbert space all bounded linear operators of which are simple
An invariant subspace of the Bergman space having the codimension two property.
An isomorphic characterization of the Schmidt class
An iterative algorithm by viscosity approximation method for mixed equilibrium problems, variational inclusion and fixed point of an infinite family of pseudo-contractive mappings
The purpose of this paper is to investigate the problem of finding a common element of the set of solutions for mixed equilibrium problems, the set of solutions of the variational inclusion problems for inverse strongly monotone mappings and the set of common fixed points for an infinite family of strictly pseudo-contractive mappings in the setting of Hilbert spaces. We prove the strong convergence theorem by using the viscosity approximation method for finding the common element of the above four...
An operator on a separable Hilbert space with many hypercyclic vectors
Angles in metric and normed linear spaces
Approximation par des variétés algébriques dans les espaces hilbertiens (Variation sur un thème de Vituškin)