Opuscula Mathematica
Opuscula Math. 43, no. 2 (2023), 185-197

Lower density operators. Φ<sub>f</sub> versus Φ<sub>d</sub>

Gertruda Ivanova
Elżbieta Wagner-Bojakowska
Władysław Wilczyński
Abstract. Using the new method of the construction of lower density operator introduced in the earlier paper of the first two authors, we study how much the new operator can be different from the classical one. The aim of this paper is to show that if \(f\) is a good adjusted measure-preserving bijection then the lower density operator generated by \(f\) can be really different from the classical density operator.
Keywords: lower density operator, measure-preserving bijection.
Mathematics Subject Classification: 54C60, 26E25, 28D05.
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About the authors ▼
Gertruda Ivanova (corresponding author)
https://orcid.org/0000-0002-1832-9491
Pomeranian University in Słupsk, Institute of Exact and Technical Sciences, Arciszewskiego 22d, 76-200 Słupsk, Poland
Elżbieta Wagner-Bojakowska
https://orcid.org/0000-0002-5916-6481
Łódź University, Faculty of Mathematics and Computer Science, Stefana Banacha 22, 90-238 Łódź, Poland
Władysław Wilczyński
https://orcid.org/0000-0002-7478-9847
Łódź University, Faculty of Mathematics and Computer Science, Stefana Banacha 22, 90-238 Łódź, Poland
About the article ▼
Communicated by Palle E.T. Jorgensen.
Received: 2022-12-29.
Revised: 2023-01-16.
Accepted: 2023-01-17.
Published online: 2023-03-27.
Cite this article as ▼
Gertruda Ivanova, Elżbieta Wagner-Bojakowska, Władysław Wilczyński, Lower density operators. Φ<sub>f</sub> versus Φ<sub>d</sub>, Opuscula Math. 43, no. 2 (2023), 185-197, https://doi.org/10.7494/OpMath.2023.43.2.185.
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