TimeSeed: History as a First-Class Object — Proof-Carrying Time Semantics for WorldSeed-Compliant Programmable Worlds and World Markets

TimeSeed is a mechanically checkable semantic layer that elevates time, history, and responsibility to first-class objects in programmable world runtimes and open world markets. TimeSeed is defined strictly as a WorldSeed extension: it operates on top of the WorldSeed world interface (S,A,B,O) and inherits the WorldSeed compliance contract. TimeSeed blocks history rewriting attacks, including rollback laundering, audit deletion, narrative forgery, responsibility transfer, and retroactive certification. It enforces non-rewriteability through an append-only event semantics, cryptographic sealing of the history chain, small-step operational semantics producing causal traces, proof-carrying histories and claims, progress/preservation theorems ensuring time cannot stall and history cannot be rewritten, refinement mappings between worlds that preserve causal legality, and a marketplace listing protocol in which uncertified artifacts cannot be traded as certified. TimeSeed is the formal semantics of time required for a WorldSeed-based civilization economy to remain auditable, compositional, and safe under adversarial incentives.