The Gunn-Peterson opacity rise at z≈6 does not require reionization. A smooth absorber density gradient produces the same onset through geometric percolation alone. Seed 1201.
Mean transmitted flux vs redshift. Smooth absorber gradient with density bias toward high-z. No reionization event coded. Onset emerges from absorber geometry alone. Seed 1201.
Mean transmitted flux for three density environments. Onset redshift shifts by ~0.9 in z — inconsistent with a fixed global reionization epoch. Seed base 2202.