P05 — Emergent Time as a Semigroup Parameter in the Selected Physical Sector

This paper is part of a coherent research program developing an informationally emergent physical framework. P05 addresses the emergence of time within the framework by showing how an effective temporal parameter arises in a selected physical sector as a semigroup evolution, rather than as a fundamental reversible time variable. The analysis builds on the loss of coherence induced by coarse-graining and the selection of dynamically stable informational configurations. The paper demonstrates that effective time evolution naturally acquires an intrinsic directionality and irreversibility, providing a structural explanation for time asymmetry without postulating it at the fundamental level. This result establishes the basis for the emergence of dynamical laws and thermodynamic behavior in later developments of the framework. While this paper can be read independently, its full significance is apparent only within the complete sequence of papers (P00–P32). The reference entry for the full framework, including priority timestamp and complete context, is:DOI: 10.5281/zenodo.18369063