Superseded (July 2026): The 170 kDa sodium-nanoparticle interference result (Pedalino et al., Nature 649, 866 (2026)) closes the $\Gamma(10^4\,\text{amu}) \in [1.2, 3.8]$ s$^{-1}$ discovery window analysed here. This document is retained as a historical derivation and assumption audit; the current position is that the natural mass channel is excluded, leaving only a sub-half-nm microscopic corner and a differential reanalysis of existing data. See the site's Experimental Evidence view for the current status.
Update (July 16, 2026). The window computed here — Γ(10⁴ amu) ∈ [1.2, 3.8] s⁻¹ at the former atom-interferometry ceiling — was closed in January 2026 by the 170 kDa sodium-nanoparticle interference record (Pedalino et al., Nature649, 866): the form-factor-corrected M²/vb transfer bounds Γ(10⁴ amu) ≲ 0.07 s⁻¹ (0.03 at 1σ), ≥17× below the predicted floor for ξ ≳ 2 nm; the 1σ sensitivity estimate lies below the window over the entire continuum range; the conservative budget excludes ξ ≳ 0.7 nm, leaving a sub-half-nm corner at the constituent-spacing scale (likelihood-level analysis pending). The remaining test is a differential M²/vb + sidereal fit on the published MUSCLE dataset. Current statement: Mathematical Supplement (July 2026).
Kelly Sonderegger · Independent Researcher, Santaquin, Utah · ksondere@gmail.com
Abstract (current summary)
This note pressure-tested the one surviving realization of ACT's optional universal channel — a non-relativistic medium comoving with the laboratory, bounded through the transfer law \(\Gamma\propto M^2/v_b\). Current status: the window is closed. The 170 kDa sodium-nanoparticle interference record (Pedalino et al., Nature 649, 866 (2026)) bounds \(\Gamma(10^4\,\text{amu})\lesssim 0.07~\text{s}^{-1}\) (0.03 at the 1σ budget), at least 17× below the predicted floor for correlation lengths \(\xi\gtrsim 2\) nm; the conservative budget excludes \(\xi\gtrsim 0.7\) nm, leaving only a sub-half-nm corner pending a likelihood-level analysis. The remaining test is a differential \(M^2/v_b\) + sidereal-phase fit on the published MUSCLE dataset.
Historical derivation archived
The full pressure test — the swept-medium law \(\Gamma = (Mc^2/\hbar)^2\varphi^2_{\rm rms}\,\xi/v_b\), the cost ledger (preferred frame, drag mechanism, tuned correlation length), and the original discovery-window figures — is retained for the record in the project archive, superseded by the closure now summarized in the site's Experimental Evidence view. It is kept out of this active page because its window numbers no longer represent ACT's position.