2026/07/22 by Christina Mahmoud
#math.NA #cs.NA
This work studies the linear Jin-Xin relaxation model by means of the relative entropy method, both at the continuous and fully discrete levels. Under the strict subcharacteristic condition, we obtain an O(ε) estimate for the convergence toward the equilibrium transport equation. We then develop discrete relative entropy estimates for a Lie splitting scheme and an asymptotic preserving staggered scheme. A fixed-time analysis further explains the O(ε2 ) behavior observed in the strongly stiff regime and the transition occurring when ε becomes comparable to the time step.