Développements récents sur les groupes de tresses. Applications à la topologie et à l'algèbre
Dicovering spaces.
Die Unterscheidung von Homotopietyp und einfachem Homotopietyp bei zweidimensionalen Komplexen.
Diffeomorphic types of the complements of arrangements of hyperplanes
Differentiable Motions of Unknotted, Unlinked Circles in 3-Space.
Discrete Dirac operators on Riemann surfaces and Kasteleyn matrices
Let be a flat surface of genus with cone type singularities. Given a bipartite graph isoradially embedded in , we define discrete analogs of the Dirac operators on . These discrete objects are then shown to converge to the continuous ones, in some appropriate sense. Finally, we obtain necessary and sufficient conditions on the pair for these discrete Dirac operators to be Kasteleyn matrices of the graph . As a consequence, if these conditions are met, the partition function of the dimer...
Discrete -groups with a parabolic generator.
Discrete Morse inequalities on infinite graphs.
Discrete Morse theory and graph braid groups.
Discrete thickness
We investigate the relationship between a discrete version of thickness and its smooth counterpart. These discrete energies are deffned on equilateral polygons with n vertices. It will turn out that the smooth ropelength, which is the scale invariant quotient of length divided by thickness, is the Γ-limit of the discrete ropelength for n → ∞, regarding the topology induced by the Sobolev norm ‖ · ‖ W1,∞(S1,ℝd). This result directly implies the convergence of almost minimizers of the discrete energies...
Discriminant d’un germe et quotients de contact dans la résolution de
Distances of Heegaard splittings.
Distortion in transformation groups (with an appendix by Yves de Cornulier).
Distribution of Points of Odd Degree of Certain Triangulations in the Plane.
Divergence in Submanifolds.
Divisibility of twisted Alexander polynomials and fibered knots
We prove that Wada’s twisted Alexander polynomial of a knot group associated to any nonabelian -representation is a polynomial. As a corollary, we show that it is always a monic polynomial of degree for a fibered knot of genus .
DNA knotting in spooling like conformations in bacteriophages.
Does the Jones polynomial detect unknottedness?
Dotted links, Heegaard diagrams, and colored graphs for PL 4-manifolds.
The present paper is devoted to establish a connection between the 4-manifold representation method by dotted framed links (or -in the closed case- by Heegaard diagrams) and the so called crystallization theory, which visualizes general PL-manifolds by means of edge-colored graphs.In particular, it is possible to obtain a crystallization of a closed 4-manifold M4 starting from a Heegaard diagram (#m(S1 x S2),ω) and the algorithmicity of the whole process depends on the effective possibility of recognizing...
Double coverings and reflexive abelian hypermaps.