Opuscula Math. 43, no. 2 (2023), 185-197
https://doi.org/10.7494/OpMath.2023.43.2.185
Opuscula Mathematica
Lower density operators. Φf versus Φd
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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- 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
- Communicated by Palle E.T. Jorgensen.
- Received: 2022-12-29.
- Revised: 2023-01-16.
- Accepted: 2023-01-17.
- Published online: 2023-03-27.
