The Holosphere: An Outside View of the Holographic Ledger

This paper originates in a thought experiment: how must a hologram and its projection surface be constructed so that an observer embedded within the bulk experiences exactly the physics of our universe — locality, causality, gravity, quantum uncertainty, and cosmological expansion — while all information is encoded on a lower-dimensional boundary? We call this construction the Holosphere. In exploring it, we find that the Holosphere is the outside-view counterpart of the Holographic Ledger (HL) framework. We construct an explicit duality mapping, derive three falsifiable joint predictions (negative dwell time scaling, coherence-entanglement correspondence, CMB boundary topology), and demarcate structural isomorphism from physical identity claims.