Äquivariantes kontrolliertes Schneiden und Kleben.
Arc presentations of knots and links
s paper presents some examples and a survey of results concerning a new way of presenting knots and links, together with the corresponding link invariant. More detailed accounts are given in [Cr, C-N, Nu1, Nu2, Nu3].
Arc-presentations of links: Monotonic simplification
In the early 90's J. Birman and W. Menasco worked out a nice technique for studying links presented in the form of a closed braid. The technique is based on certain foliated surfaces and uses tricks similar to those that were introduced earlier by D. Bennequin. A few years later P. Cromwell adapted Birman-Menasco's method for studying so-called arc-presentations of links and established some of their basic properties. Here we further develop that technique and the theory of arc-presentations, and...
Arcs in the Hilbert cube whose complements have different fundamental groups
Area functionals and Godbillon-Vey cocycles
We investigate the natural domain of definition of the Godbillon-Vey 2- dimensional cohomology class of the group of diffeomorphisms of the circle. We introduce the notion of area functionals on a space of functions on the circle, we give a sufficiently large space of functions with nontrivial area functional and we give a sufficiently large group of Lipschitz homeomorphisms of the circle where the Godbillon-Vey class is defined.
Area preserving group actions on surfaces.
Area preserving pl homeomorphisms and relations in
To any compactly supported, area preserving, piecewise linear homeomorphism of the plane is associated a relation in of the smallest field whose elements are needed to write the homeomorphism.Using a formula of J. Morita, we show how to calculate the relation, in some simple cases. As applications, a “reciprocity” formula for a pair of triangles in the plane, and some explicit elements of torsion in of certain function fields are found.
Area preserving twist homeomorphism of the annulus.
Arithmetic groups of gauge transformations.
Arithmetic hyperbolic surface bundles.
Arithmetic of an elliptic curve and circle actions on four-manifolds
Around the Borromean link.
This is a survey of some consequences of the fact that the fundamental group of the orbifold with singular set the Borromean link and isotropy cyclic of order 4 is a universal kleinian group.
Arrangements with one Bounded component and p-adic integrals.
Arrondissement des variétés à coins - Appendice à "Corners and Arithmetic Groups"
Artin groups of finite type are biautomatic.
ASD moduli spaces over four-manifolds with tree-like ends.
Aspherical 2-Complexes and an Unsettled Problem of J. H. C. Whitehead.
Aspherical four-manifolds and the centres of two-knot groups.
Aspherical Group Presentations.
Aspherical Manifolds and Higher-Dimensional Knots