Finite element solution of nonlinear elliptic equations with discontinuous coefficients and approximations in Sobolev-Slobodeckij spaces
Let be a cell complex obtained by attaching a 2-cell to a finite bouquet of circles (for example, a closed surface). In terms of the combinatorial type of the attaching map, the paper gives conditions for the existence of a fixed point free (topological) homeomorphism of the complex . Also, quotients of finite group actions on such complexes are considered as well as a condition under which the induced actions on cohomology are trivial.
[For the entire collection see Zbl 0699.00032.] The author defines a general notion of a foliated groupoid over a foliation with singularities, within the framework of a (known) general notion of a differentiable structure. Then, he generalizes the classical correspondence between the subalgebras of Lie algebras and the subgroups of the corresponding Lie groups for this type of pseudogroups.