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The radial acceleration relation (RAR) revealed by the SPARC survey - a tight, nearly galaxy-independent correlation between observed and baryonic accelerations, controlled by a single scale $g_\dagger\sim 10^{-10}\ \mathrm{m\,s^{-2}}$ - remains unexplained within standard $\Lambda$CDM. We propose that this scale is the gravitational imprint of a representation-theoretically protected infrared spectral gap in a coherent gluonic dark sector. The argument follows a single logical chain. At the QCD epoch, colour confinement freezes a long-lived population of colour-singlet (scalar di-gluonic) bound states into a sector decoupled from the baryonic plasma. The QCD trace anomaly, through dimensional transmutation, generates a dynamical infrared scale in this sector. Requiring Lorentz covariance together with a positive-energy lowest-weight unitary realization then selects $\mathrm{SO}(2,3)$ - the isometry group of Anti-de Sitter space - as the natural symmetry of the infrared dynamics. The associated discrete Fronsdal spectrum carries a gap that is representation-theoretically protected, and its lowest scalar mode (conformally coupled, $\zeta=2$) undergoes Bose-Einstein condensation without any external trap. The resulting condensate halo has a finite total mass, a cored density profile $\rho\propto(1+r^2/r_c^2)^{-2}$, and an intrinsic acceleration scale $g_\star = GM_h/r_c^2$ naturally of order $g_\dagger$ - without fine-tuning and without modifying gravity.
Reference: Gilles Cohen-Tannoudji, Jean-Pierre Gazeau, Hamed Pejhan, and Jean-Pierre Treuil, Infrared Spectral Gap in a Gluonic Dark Sector as the Origin of the Galactic Acceleration Scale, arXiv:2604.12910v1 [hep-th]