2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/79762Recently, stretched exponential decay of multiple correlations in the periodic Lorentz gas has been used to show the convergence of a series of correlations which has the physical interpretation as the fourth order Burnett coefficient, a generalisation of the diffusion coefficient. Here the result is extended to include all higher order Burnett coefficients, and give a plausible argument that the expansion constructed from the Burnett coefficients has a finite radius of convergence.11 pages; no figures. This paper uses and extends the results given in chao-dyn/9910008 . Version 2 revised for greater mathematical clarityChaotic DynamicsStatistical MechanicsMathematical Physicstext