En utilisant des méthodes de topologie à grande échelle, on prouve que les classes fondamentales des variétés agrandissables ne s’annulent pas, ni dans l’homologie rationnelle de leurs groupes fondamentaux, ni dans la -théorie des -algèbres réduites correspondantes. Nos résultats ne dépendent pas de la conjecture de Baum-Connes, et confirment de façon indépendante certaines conséquences de cette conjecture.
Using methods from coarse topology we show that fundamental classes of closed enlargeable manifolds map non-trivially both to the rational homology of their fundamental groups and to the -theory of the corresponding reduced -algebras. Our proofs do not depend on the Baum-Connes conjecture and provide independent confirmation for specific predictions derived from this conjecture.
@article{ASENS_2008_4_41_3_473_0, author = {Hanke, Bernhard and Kotschick, Dieter and Roe, John and Schick, Thomas}, title = {Coarse topology, enlargeability, and essentialness}, journal = {Annales scientifiques de l'\'Ecole Normale Sup\'erieure}, volume = {41}, year = {2008}, pages = {473-495}, doi = {10.24033/asens.2073}, mrnumber = {2482205}, zbl = {1169.53032}, language = {en}, url = {http://dml.mathdoc.fr/item/ASENS_2008_4_41_3_473_0} }
Hanke, Bernhard; Kotschick, Dieter; Roe, John; Schick, Thomas. Coarse topology, enlargeability, and essentialness. Annales scientifiques de l'École Normale Supérieure, Tome 41 (2008) pp. 473-495. doi : 10.24033/asens.2073. http://gdmltest.u-ga.fr/item/ASENS_2008_4_41_3_473_0/
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