Resolving Nonlocal State Reduction via Induced Coherence in Frequency-Comb Biphoton Sources

Abstract:How macroscopic definite outcomes and nonlocal correlations emerge from entangled superpositions across spacelike-separated regions without superluminal action or {\it ad hoc} wavefunction collapse remains a defining open question in the foundations of quantum mechanics. Here, we resolve this century-long paradox within \textit{linear} relativistic quantum electrodynamics by developing an open-system and measurement-defined framework realized in dual, spacelike-separated nonlinear crystals driven synchronously by a multi-mode optical frequency comb and seeded by an ultra-narrow coherent laser. Expanding the transverse electromagnetic vector potential into discrete single-photon frequency-comb supermodes, we show that tracing out the unmeasured continuous-wave idler field yields an exact spatial dephasing Lindblad master equation whose decoherence rate is governed by the non-orthogonal state overlap of single-photon-added coherent states. Connecting this open-system map to free-vector-space quotient measurement theory, we demonstrate that single-particle interference arises from the geometric projection of the composite state onto detector-defined conditional cosets rather than remote collapse, establishing strict operational equivalence across pump, seed, and signal phase scans. The resulting wave-particle-entanglement triality equality $P^2 + E^2 + V^2 = 1$ is saturated across the complete parameter space, while the atomic-clock-referenced comb structure anchors continuous-variable time-frequency displacement stabilizers directly at the hardware layer. Our work unifies induced coherence, Bohr's complementarity, and quotient measurement theory, providing a microscopic pathway toward fault-tolerant bosonic quantum information processing.

arXiv:2610.27602 [quant-ph]

(or arXiv:2610.27602v1 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2610.27602 Focus to learn more arXiv-issued DOI via DataCite (pending registration)

arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website.

Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them.

Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs.