Integrability breaking in the Rule 54 cellular automaton

Cellular automata have recently attracted a lot of attention as testbeds to explore the emergence many-body quantum chaos and hydrodynamics. We consider Rule 54 model, one simplest interacting integrable models featuring two species quasiparticles (solitons), in presence an integrability-breaking perturbation that allows solitons backscatter. study onset thermalization diffusive hydrodynamics this compute perturbatively diffusion constant tracer particles, comment on its relation transport coefficients.