Dans cet article nous démontrons l'existence de structures d'Einstein sasakiennes sur certaines 7-sphères d'homologie rationnelle, 2-connexes. Elle apparaissent comme étant les premiers exemples non réguliers de métriques d'Einstein sasakiennes sur les sphères d'homologie rationnelle, simplement connexes. Nous décrivons aussi brièvement les 7- sphères d'homologie rationnelle qui admettent des structures sasakiennes positives régulières.
In this paper we demonstrate the existence of Sasakian-Einstein structures on certain 2- connected rational homology 7-spheres. These appear to be the first non-regular examples of Sasakian-Einstein metrics on simply connected rational homology spheres. We also briefly describe the rational homology 7-spheres that admit regular positive Sasakian structures.
@article{AIF_2002__52_5_1569_0, author = {Boyer, Charles P. and Galicki, Krzysztof and Nakamaye, Michael}, title = {Einstein metrics on rational homology 7-spheres}, journal = {Annales de l'Institut Fourier}, volume = {52}, year = {2002}, pages = {1569-1584}, doi = {10.5802/aif.1925}, zbl = {1023.53029}, language = {en}, url = {http://dml.mathdoc.fr/item/AIF_2002__52_5_1569_0} }
Boyer, Charles P.; Galicki, Krzysztof; Nakamaye, Michael. Einstein metrics on rational homology 7-spheres. Annales de l'Institut Fourier, Tome 52 (2002) pp. 1569-1584. doi : 10.5802/aif.1925. http://gdmltest.u-ga.fr/item/AIF_2002__52_5_1569_0/
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