Environmental Imprints as Spatial Proof-of-Presence in Multi-Reference Location Validation

Conventional location systems treat position as a signal to be reported, authenticated, and verified.Such signals can be relayed, replayed, or synthesized, enabling adversaries to fabricate coherent butfalse locations. This paper argues that trustworthy location validation must be grounded not incoordinates, but in environmental exposure. Local environments leave persistent biological,chemical, and physical imprints on devices, substrates, and organisms. These imprints encodeevidence of prolonged presence that cannot be retroactively fabricated. We introduce the conceptof spatial proof-of-presence, in which location claims are validated through correlation of multipleenvironmental signatures across timescales. This work extends prior research on biological,chemical, and physical hysteresis for temporal validation, reframing those principles as spatialconstraints on plausible location histories.