Adjudication at the Worldline: Consolidated Price Discovery Is Physically Undefined; Local Arrival-Order Matching Relocates It, and the Co-location Premium with It

The National Best Bid and Offer (NBBO), the consolidated "now" at the centre of U.S. equity market structure under Regulation NMS, requires comparing price events at exchanges whose separation places those events outside one another's light cones. For such spacelike-separated events special relativity makes temporal order frame-dependent: there is no observer-independent fact about which quote is "current," and the consolidated best bid and offer is therefore not a measurement of the market but an artefact of one simultaneity convention. We restate this impossibility precisely and then make the constructive point that follows from it. A matching engine does not, in fact, rely on global time; it adjudicates by arrival order at a single point, which is a total, local, frame-invariant order. The defect is its singularity, not the principle: the entire co-location arms race is the cost of racing toward one privileged adjudication point. We propose relocating adjudication from that one conventional oracle to a local, physical oracle at each participant's own worldline, so that every node is the centre of its own light cone and simultaneity is constructed by a completed bilateral handshake rather than measured against a shared clock. Under this construction market centrality becomes relative: price discovery can occur from anywhere rather than only from the handful of captive co-location halls, the latency arms race that Budish, Cramton and Shim identify as socially wasteful loses its prize rather than merely being slowed, and the deterministic-completion skill that HFT firms have built becomes positive-sum. We give a falsifiable prediction distinguishing the two designs and discuss the limits set by the speed of light, liquidity fragmentation, and incumbent rents. JEL: G14; G18; D47.