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

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)
  • ORCID iD https://orcid.org/0000-0002-1832-9491
  • Pomeranian University in Słupsk, Institute of Exact and Technical Sciences, Arciszewskiego 22d, 76-200 Słupsk, Poland
  • Communicated by Palle E.T. Jorgensen.
  • Received: 2022-12-29.
  • Revised: 2023-01-16.
  • Accepted: 2023-01-17.
  • Published online: 2023-03-27.
Opuscula Mathematica - cover

Cite this article as:
Gertruda Ivanova, Elżbieta Wagner-Bojakowska, Władysław Wilczyński, Lower density operators. Φf versus Φd, Opuscula Math. 43, no. 2 (2023), 185-197, https://doi.org/10.7494/OpMath.2023.43.2.185

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