http://popups.lib.uliege.be/1373-5411/index.php?id=3118 In this paper, entropy is portrayed as a property which is dependent on the levels of description (LODs) taken into account. LODs are abstractions in terms of which an observed system may be described. They highlight different qualitative or quantitative aspects of a system. For nested systems, the outcome of a measurement depends on the observer's position and extension, his internal differentiation and assignment conditions. The concept of interface complexity as a measure of entropy is introduced. Finally, a differentiation is suggested between ΔS (endo), ΔS (pseudo-exo) and ΔS (exo), which correspond to the inside, pseudo-outside and outside perspectives, respectively. Full text issues Volume 17 Physical Systems, Quantum Mechanics and Relativity fr Mon, 09 Sep 2024 09:35:54 +0200 Mon, 09 Sep 2024 09:36:04 +0200 http://popups.lib.uliege.be/1373-5411/index.php?id=3118 0