3 papers
math.FA2025
Similarities of subspace lattices in Banach spaces
Janko Bračič, Marko Kandić
A collineation of a subspace lattice $\fL$ in a complex Banach space $\eX$ is an invertible operator on $\eX$ with the property that the image $S\eM$ of a subspace $\eM$ belong…
math.FA2022
Hyperinvariant subspaces for sets of polynomially compact operators
Janko Bračič, Marko Kandić
We prove the existence of a non-trivial hyperinvariant subspace for several sets of polynomially compact operators. The main results of the paper are: (i) a non-trivial norm closed…
math.FA2021
Local commutants and ultrainvariant subspaces
Janko Bračič
For an operator on a complex Banach space and a closed subspace , the local commutant of at is the set of all operators on such that…