No Entanglement Without a Common Origin — A Naturalistic Principle

It is well known that entangled quantum systems can be prepared in laboratories via spontaneous parametric down-conversion, controlled interactions, and entanglement swapping. In nature, however, such engineered processes are absent. This paper examines all known or plausibly natural sources of entanglement — including pair production, radioactive decay, radical-pair reactions, particle scattering, and hypothetical cosmological scenarios — and finds a unifying pattern: natural entanglement arises only when the entangled systems share a past quantum unity, either as a single parent system that splits into two or more daughters, or as two initially separate systems that temporarily merge into a single undivided quantum state before separating. By contrast, entanglement swapping and quantum teleportation (including satellite-based demonstrations such as the Chinese Micius experiments) are shown to be engineered processes that do not occur spontaneously in nature. Moreover, a close reading of the Micius experiments reveals that the entangled bridge itself requires a common origin, and the teleportation protocol requires classical communication and conditional operations absent in natural settings. Bell's theorem is discussed as a supporting but non‑essential component: it rules out local hidden variable explanations of entanglement but does not address the question of whether entanglement can arise without a shared past. The proposed principle, if empirically robust, suggests that entanglement in the wild is always a vestige of contact — a signature of past unity rather than a mysterious link between strangers.