Quantum-optimal measurements for multi-telescope interferometry

Determine whether measuring each telescope pair separately is quantum-optimal, or whether quantum states and joint measurements shared across more than two telescopes can extract image information more efficiently.

Background

The paper explains that extending quantum-assisted interferometry from a single baseline to an imaging array is not automatic. Although prior proposals describe multi-station entanglement and reference states, the efficiency of pairwise measurements relative to genuinely joint measurements across multiple telescopes remains unresolved. The question is especially relevant for imaging systems with more than two stations, where multi-telescope quantum states and joint receivers might provide information-processing advantages beyond independent baseline measurements.

References

Can three stations recover closure phase? Measure closure phase on a thermal source for simple image reconstruction.

— Development of quantum technologies for optical/infrared interferometry  (2609.04311 - Monnier, 3 Sep 2026) in Section 7, “Next experiments,” item 4

The open question is whether measuring each pair separately is quantum-optimal, or whether quantum states and joint measurements shared across $N>2$ telescopes can extract that information more efficiently.

— Development of quantum technologies for optical/infrared interferometry  (2609.04311 - Monnier, 3 Sep 2026) in Section 3.3, “More than two telescopes”

The collective receiver of Sec.~\ref{sec:receiver} is an explicit, near-optimal example (within ${\sim}7\%$ of the SLD bound), but a measurement that provably attains the Holevo bound is not yet constructed.

— Multiparameter quantum bounds for entanglement-assisted aperture synthesis  (2609.10111 - Madhav et al., 9 Sep 2026) in Section Discussion, Scope and limitations, item (i)