The Coherence Number from Orbit: What CAL and MAIUS-1 Already Bound, What They Cannot Reach, and the Measurement That Would Price π©
Year: 2026
Type: preprint
Abstract: The corpus's bounce is conditional on one unmeasured number. With π© = n_f V_c β fermion density times spin-coherence volume at bounce conditions β the bounce exists if π© β² 1β10Β², stands at its published numbers if π© β 1β2, and does not exist if the coherence length is any fixed physical length, which gives π© = 2.15Γ10Β³βΈ. No real material, at any density, has a priced π©. This paper asks what the best free-fall coherence record in existence β the Cold Atom Lab (CAL) on the International Space Station and the MAIUS-1 sounding-rocket interferometers β already implies for the π© programme, what it cannot reach, and what measurement would. The verdict is printed at full size. Read in the only dimensionless form that travels, π©_lab = n ΞΎΒ³, the orbital condensates are coherent over 10β΅β10βΈ particles: if that value could be transplanted to bounce conditions the gate would be shut, not open. It cannot be transplanted β the orbital systems are dilute bosons at nanokelvin, the bounce system is dense fermions 28 orders of magnitude denser β and the paper builds the bridge that would be needed, names the joint where it is still open, and specifies the measurement that closes it: a degenerate, spin-mixed Fermi gas in persistent microgravity, measuring the spin correlation length directly, across degeneracy and interaction, to Β±10% in length (Β±30% in π©), so that the correlation physics β not a decree β is what gets evaluated at bounce density. Design only. No hardware is proposed for fabrication, and the fabrication gate stands.
Author: Aldred, William Alexander
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7225339379