V01.11 — Mirror Physics V: Entropy, Time and Constraint Dissolution

This paper is the fifth paper in the Physics Support Arc of the Mirror Programme, Volume I: Observerhood. It follows V01.07 — Mirror Physics I: Constraint Propagation and the Physical Conditions for Observerhood, V01.08 — Mirror Physics II: Constraint Salience and Physical Coupling, V01.09 — Mirror Physics III: Thermodynamic Observerhood, and V01.10 — Mirror Physics IV: Causal Invariance and the Speed of Constraint Propagation. Mirror Theory treats observerhood not as a primitive, but as a derived organisational condition: a bounded system becomes observer-like when it maintains a viability-relevant world-model, self-model, reliability structure and identity-continuity under perturbation. Earlier papers in the physics arc argued that such systems require physical support conditions, measurable constraint salience, thermodynamic maintenance and bounded causal update. The present paper adds the temporal component. It argues that persistent observerhood requires an asymmetric temporal structure because memory, prediction, repair, learning and identity-governance are not time-neutral from the standpoint of viability. A local observer must form records of prior interaction, use them to regulate present action, predict possible future states and spend energy to maintain organisation against constraint dissolution. The paper does not modify thermodynamics, statistical mechanics, relativity or quantum theory. Instead, it reframes entropy increase and temporal direction as the background physical conditions against which local observerhood becomes a constraint-maintenance process. The central result is an Arrow of Observerhood condition: if a bounded system preserves identity-continuity through memory-governed, viability-regulated update, then it necessarily distinguishes past records, present regulation and future viability in a physically asymmetric way. Observerhood is therefore not merely information processing in time; it is entropy-bearing constraint maintenance across time.