activity
20232026
collaborators

7 papers

math.CA2026

More on dominated and microscopic sets

Ondřej Zindulka, Piotr Nowakowski, Cristina Villanueva-Segovia

Let be a family of sequences decreasing to zero. A set in a metric space is -dominated if, for every , there exists a countable cover of such that…

math.CA2026

A characterization of uniqueness of purely atomic finite measures with central Cantor set range

Piotr Nowakowski, Franciszek Prus-Wiśniowski

We study purely atomic measures whose range is a central Cantor set and characterize those central Cantor sets that are the range of exactly one such measure. Next, we extend the c…

math.CA2026

Dominated sets, microscopic sets and Hausdorff measures

Ondřej Zindulka, Piotr Nowakowski

Let be a family of sequences of positive numbers that decrease to 0, let be a metric space and . is said to be -dominated if, for every , a coun…

math.GN2025

Spectre operator, achievement sets and sets of P-sums in a hyperspace of compact sets

Piotr Nowakowski, Franciszek Prus-Wiśniowski, Filip Turoboś

Let be an Abelian metric group and . We investigate the spectre of a set , defined as the set of all elements such that for every either…

math.DS2025

The Lebesgue measure of boundaries of multigeometric Cantorvals

Piotr Nowakowski, Franciszek Prus-Wiśniowski

We prove that the boundary of every multigeometric Cantorval is a null set, and extend this result to a larger class of standard achievable Cantorvals. In addition, we discuss the…

math.CA2025

The algebraic difference of a Cantor set and its complement

Piotr Nowakowski, Cheng-Han Pan

Let be a Cantor set. In the classical problems, modifying the ``size'' of has a magnified effect on $\mathcal{…

math.CA2023

Algebraic sums of achievable sets involving Cantorvals

Jacek Marchwicki, Piotr Nowakowski, Franciszek Prus-Wiśniowski

In this paper we look at the topological type of algebraic sum of achievement sets. We show that there is a Cantorval such that the algebraic sum of its copies is still a Canto…