18 citations · 18 across the 5 of their papers we have counts for
7 papers · 1 filter
A Wigner-type theorem in Banach spaces
Lajos Molnar
We obtain an anlogue of Wigner's classical theorem on symmetries for Banach spaces. The proof is based on a result from the theory of linear preservers. Moreover, we present two ot…
Some characterizations of the automorphisms of and
Lajos Molnar
We present some nonlinear characterizations of the automorphisms of the operator algebra and the function algebra by means of their spectrum preserving properties.
On certain automorphisms of sets of partial isometries
Lajos Molnar
Under the mild condition of continuity at a single point we describe all the bijections of the set of all partial isometries on a Hilbert space which preserve the order and the ort…
On isomorphisms of standard operator algebras
Lajos Molnar
The aim of this paper is to show that between standard operator algebras every bijective map with a certain multiplicativity property related to Jordan triple isomorphisms of assoc…
Local automorphisms of the unitary group and the general linear group on a Hilbert space
Lajos Molnar, Peter Semrl
We prove that every 2-local automorphism of the unitary group or the general linear group on a complex infinite-dimensional separable Hilbert space is an automorphism. Thus these t…
On some automorphisms of the set of effects on Hilbert space
Lajos Molnar
The set of all efects on a Hilbert space has an affine structure (it is a convex set) as well as a multiplicative structure (it can be equipped with the so-called Jordan triple pro…