“…The well-posedness problem for the Boltzmann equation is a large and important research area; we will not address questions of this type in this work, but refer, for instance, to [4,5,6,7,8,9,10,14,19,34,35,25,50,52,53,54,78,81,85,86,105,107,110,108,116,117,149,155,156,157,158,165,202,201,203,207,208,209,211] and references therein.…”