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Some topics concerning homeomorphic parameterizations.

Stephen Semmes (2001)

Publicacions Matemàtiques

In this survey, we consider several questions pertaining to homeomorphisms, including criteria for their existence in certain circumstances, and obstructions to their existence.

Sur certaines équivalences d'homotopies

M. Aubry, Jean-Michel Lemaire (1991)

Annales de l'institut Fourier

On sait qu’il y a 144 classes d’homotopies d’applications de S 3 × S 3 dans lui-même dont la restriction à S 3 S 3 est homotope à l’identité: ce sont des exemples d’applications qui induisent l’identité en homologie et en homotopie. Plus généralement, soit X un complexe de Poincaré 1-connexe de dimension n , qui n’a pas le type d’homotopie rationnelle de S n : si X est formel, nous montrons que le groupe des classes d’homotopies d’applications de X dans X , dont la restriction au ( n - 1 ) -squelette est homotope à l’identité,...

The cell-like approximation theorem in dimension 5

Robert J. Daverman, Denise M. Halverson (2007)

Fundamenta Mathematicae

The cell-like approximation theorem of R. D. Edwards characterizes the n-manifolds precisely as the resolvable ENR homology n-manifolds with the disjoint disks property for 5 ≤ n < ∞. Since no proof for the n = 5 case has ever been published, we provide the missing details about the proof of the cell-like approximation theorem in dimension 5.

The generalized Schoenflies theorem for absolute suspensions

David P. Bellamy, Janusz M. Lysko (2005)

Colloquium Mathematicae

The aim of this paper is to prove the generalized Schoenflies theorem for the class of absolute suspensions. The question whether the finite-dimensional absolute suspensions are homeomorphic to spheres remains open. Partial solution to this question was obtained in [Sz] and [Mi]. Morton Brown gave in [Br] an ingenious proof of the generalized Schoenflies theorem. Careful analysis of his proof reveals that modulo some technical adjustments a similar argument gives an analogous result for the class...

The geometry of abstract groups and their splittings.

Charles Terence Clegg Wall (2003)

Revista Matemática Complutense

A survey of splitting theorems for abstract groups and their applications. Topics covered include preliminaries, early results, Bass-Serre theory, the structure of G-trees, Serre's applications to SL2 and length functions. Stallings' theorem, results about accessibility and bounds for splittability. Duality groups and pairs; results of Eckmann and collaborators on PD2 groups. Relative ends, the JSJ theorems and the splitting results of Kropholler and Roller on PDn groups. Notions of quasi-isometry,...

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