Zero-DOF Gravity Without Dark Matter: Strong Lensing to Cluster Scales via an Effective Fifth-Force Term

We present a closed-form, zero-degree-of-freedom (0-DOF) framework that reproduces stronglensing and dynamical observables from galaxies to clusters without particle dark matter. Theextra term acts as an effective fifth force fully determined by the baryonic mass distribution.We validate against: (i) a global H0 from CMB+BAO; (ii) time-delay cosmography with oneglobal f∗; (iii) SLACS strong lensing with a single aperture factor; (iv) SPARC/BTFR withlog Mb = log A + 4 log Vf (A = 47); (v) colliding clusters via κ–X-ray centroid offsets andaperture-mass comparisons; and (vi) projected Jeans diagnostics (ATLAS3D/MaNGA). All testsuse 0 tuning per object. We show that galaxy-scale strong lensing is explained with nodark matter. Some lensing tests could not be run to completion only due to missing publicFITS in this workspace, not model limitations.