Several giant gravitationally lensed arcs in galaxy clusters have angular sizes substantially larger than ΛCDM lensing models predict (Sharon 2005; Gladders 2003). The mismatch suggests either more concentrated cluster mass, systematically different source redshifts, or incorrect mass-density-profile predictions. The persistence across multiple clusters indicates systematic problems rather than random error. The Giant Arc itself extends ~3.3 Gly at z ≈ 0.8.
The standard model predicts giant-arc angular sizes from cuspy NFW cluster mass distributions plus standard cosmological geometry. Recovering the observed larger angular sizes demands either modified mass profiles or revised source-redshift estimates, neither of which is parsimonious within minimal ΛCDM.
SCT replaces the hot-dense-center with a superluminal collision and the thermalized debris field. From this single change, the Giant Arc (and similar gigaparsec-scale structures) is a first-stage cascade-collision arc signature inherited at deposition rather than assembled gravitationally. The cascade has a finite largest characteristic scale Λ_max ≈ 5 Gpc set by parent-pocket size (P22, P34, P55).
The Giant Arc joins the broader gigaparsec-wall-and-arc population: Hercules-Corona Borealis Wall (recid 100), Big Ring (recid 85), Sloan Great Wall (recid 99), CfA2 Great Wall (recid 94), and Huge-LQG (recid 103). All members of the cascade-deposited large-scale anomalous-structure family with characteristic sizes determined by cascade-stage geometry. Multi-stage cascade dynamics (P36, P37, P38) provides the formation context for these features.
The angular-size apparent excess relative to ΛCDM predictions reflects the cascade-deposited geometric structure rather than late-time gravitational assembly. Gravitational superposition (P50, P51, P52) gives apparent lensing dynamics through the Φ_mesh contribution. The same M4 framework that produces the Hercules-CB Wall (recid 100), Sloan Great Wall (recid 99), Big Ring (recid 85), and the broader gigaparsec-population accounts for the Giant Arc as a predicted cascade-stream-event signature.
If precision Euclid + DESI + LSST surveys find no gigaparsec-scale arc population beyond cosmic-variance expectations (no 3 to 7 per observable patch population matching cascade-stream demographics), the M4 cascade-collision arc explanation is refuted. The signature SCT prediction is the gigaparsec-arc population at Λ_max ≈ 5 Gpc with predictable demographics.