The quasi-2D transition module (transition_dp_2d.py)

Extends the transition test ( §3) to quasi-2D. The same G-SOC rules run on an L× L lattice with 4 neighbours (so the absorbing transition is in the (2+1)d directed-percolation class); the reserves (θ=0.45) and re-jam (q=0.35) are unchanged.

)} Extends the transition test (\S§3) to quasi-2D. The same G-SOC rules run on an L× L lattice with 4 neighbours (so the absorbing transition is in the (2+1)d directed-percolation class); the reserves (θ=0.45) and re-jam (q=0.35) are unchanged.

)} Extends the transition test (\S§3) to quasi-2D. The same G-SOC rules run on an $L\times L$ lattice with 4 neighbours (so the absorbing transition is in the (2{+}1) d directed-percolation class); the reserves ( $\theta=0.45$ ) and re-jam ( q=0.35 ) are unchanged. $\lambda_c$ is located by the survival transition (bracketed by whether the active density reaches a plateau or falls to the absorbing state, then bisected), and the turbulent-fraction box roughness $M_2(r)-1=\langle\rho_r^2\rangle/\langle\rho_r\rangle^2-1$ is measured on $r\times r$ coarse-grainings of the critical quasi-stationary state, fitted in the small- scaling regime over six realisations at L=384 . The result is $2\beta/\nu_\perp=1.475\pm0.058$ against the (2{+}1) d DP value 1.591 ; with the quasi-1D measurement ( 0.482 ) the 2D/1D ratio is 3.06 against the DP 3.16 . Captured output and the per-realisation values ship with the module.