1 citations · 1 across the 5 of their papers we have counts for
5 papers
Weighted shifts on directed forests and hyponormality
Piotr Pikul
In a paper from 2012 Jabłoński, Jung and Stochel introduced the weighted shifts on directed trees, a generalisation of well known weighted shift operators on . In the last…
Joint backward extension property for weighted shifts on directed trees
Piotr Pikul
Weighted shifts on directed trees are a decade old generalisation of classical shift operators in the sequence space . In this paper we introduce the joint backward extensi…
Backward extensions of weighted shifts on directed trees
Piotr Pikul
The weighted shifts are long known and important class of operators. One of known generalisation of this class are weighted shifts on directed trees, where we replace the linear or…
Locally ordered topological spaces
Piotr Pikul
While topology given by a linear order has been extensively studied, this cannot be said about the case when the order is given only locally. The aim of this paper is to fill this…
Hyperbolic geometry for non-differential topologists
Piotr Niemiec, Piotr Pikul
A soft presentation of hyperbolic spaces, free of differential apparatus, is offered. Fifth Euclid's postulate in such spaces is overthrown and, among other things, it is proved th…