  Existence of global regular solution branches of the Boltzmann Cauchy problem
with continuously differentiable data in phase space dimension $2d\geq 6$ with
polynomial decay at infinity of order greater than $2d$ is proved. There are
data in this class of infinite relative entropy with respect to the Gaussian.
Furthermore, there are weakly singular solution branches of the Boltzmann
equation in spatial dimension $d\geq 3$, i.e., solutions of the Boltzmann
equations which are only Lipschitz with respect to the velocity variables at
some point in phase space. This is in accordance with a.e. $L^1$-uniqueness of
renormalized solutions (cf.\cite{L}) and more classical results in function
spaces of mixed regularity.
