Asymmetric-Loss Equal-Born Test: proposal for a host laboratory and first-run equipment list

Why this measurement is worth a bench: see section 2 of the proposal, "Why anyone should want to measure it". Contact: [email protected]. Two companion documents to the deposited paper, doi:10.5281/zenodo.22678044, and its pre-registration, osf.io/3h6yf. The question: does a 50/50 beam splitter transmit a single photon in exactly the same proportion as it transmits bright light? Standard linear optics says yes, exactly. The first run compares the two to one part in a thousand, with one source; only a calibrated attenuator changes between the bright phase and the single-photon phase. ALEBT_proposal_paper_v1_oct20.pdf: the proposal written for a host laboratory (the observable, the hypothesis, the error budget, the stages, the equipment and the open problems). ALEBT_equipment_list_v2_oct26.pdf: the first-run equipment list, with answers to the questions raised by groups we have written to (existing measurements, fibre-coupled detectors, differences between detectors).