We consider Lipschitz mappings, , where X is a doubling metric measure space which satisfies a Poincaré inequality, and V is a Banach space. We show that earlier differentiability and bi-Lipschitz nonembedding results for maps, , remain valid when is replaced by any separable dual space. We exhibit spaces which bi-Lipschitz embed in , but not in any separable dual V. For certain domains, including the Heisenberg group with its Carnot–Caratheodory metric, we establish a new notion of differentiability for maps into . This implies that the Heisenberg group does not bi-Lipschitz embed in , thereby proving a conjecture of J. Lee and A. Naor. When combined with their work, this has implications for theoretical computer science.
Nous considérons des applications lipchitziennes, , où X est un espace métrique mesuré tel que l'on contrôle le volume des boules par doublement du rayon et qui satisfait à une inégalité de Poincaré, et où V est un espace de Banach. On montre que des résultats antérieurs de différentiabilité et de non plongement bilipschitzien pour des applications , restent valables quand on suppose que V est un dual séparable. Nous donnons des exemples d'espaces plongés de manière bilipschitzienne dans , mais qui ne sont plongeables dans aucun dual séparable. Pour certains espaces, dont le groupe d'Heisenberg muni de la métrique de Carnot–Caratheodory, on établit une nouvelle notion de différentiabilité pour des applications dans . Ceci implique que le groupe de Heisenberg ne possède aucun plongement bilipschitzien dans , un résultat conjecturé par J. Lee et A. Naor. Quand il est combiné avec des résultats de ces deux auteurs, notre travail a des applications en informatique théorique.
Accepted:
Published online:
Jeff Cheeger 1; Bruce Kleiner 2
@article{CRMATH_2006__343_5_297_0, author = {Jeff Cheeger and Bruce Kleiner}, title = {Generalized differentiation and {bi-Lipschitz} nonembedding in $ {L}^{1}$}, journal = {Comptes Rendus. Math\'ematique}, pages = {297--301}, publisher = {Elsevier}, volume = {343}, number = {5}, year = {2006}, doi = {10.1016/j.crma.2006.07.001}, language = {en}, }
Jeff Cheeger; Bruce Kleiner. Generalized differentiation and bi-Lipschitz nonembedding in $ {L}^{1}$. Comptes Rendus. Mathématique, Volume 343 (2006) no. 5, pp. 297-301. doi : 10.1016/j.crma.2006.07.001. https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.1016/j.crma.2006.07.001/
[1] Differentiability of Lipschitzian mappings between Banach spaces, Studia Math., Volume 57 (1976) no. 2, pp. 147-190
[2] Geometric Nonlinear Functional Analysis, vol. 1, Amer. Math. Soc. Colloq. Publ., vol. 48, American Mathematical Society, Providence, RI, 2000
[3] Poincaré inequalities and quasiconformal structure on the boundary of some hyperbolic buildings, Proc. Amer. Math. Soc., Volume 127 (1999) no. 8, pp. 2315-2324
[4] Differentiability of Lipschitz functions on metric measure spaces, Geom. Funct. Anal., Volume 9 (1999) no. 3, pp. 428-517
[5] On the structure of spaces with Ricci curvature bounded below, J. Differential Geom., Volume 46 (1997), pp. 406-480
[6] J. Cheeger, B. Kleiner, Differentiating Banach space valued functions on metric measure spaces, Preprint, 2005
[7] J. Cheeger, B. Kleiner, Differentiating maps to and the geometry of BV functions, Preprint, 2006
[8] J. Cheeger, B. Kleiner, Embedding Laakso spaces in , Preprint, 2006
[9] Abstrakte Functionen und lineare Operatoren, Mat. Sb., Volume 46 (1938) no. 4, pp. 235-284
[10] Carnot–Caratheodory spaces seen from within, Sub-Riemannian Geometry, Progr. in Math., Birkhäuser, Basel, 1996, pp. 79-323
[11] From local to global in quasiconformal structures, Proc. Nat. Acad. Sci. USA, Volume 93 (1996), pp. 554-556
[12] S. Khot, N. Vishnoi, The unique games conjecture, integrality gap for cut problems and embeddability of negative type metrics into , in: 46th Annual Symposium on Foundations of Computer Science, IEE Computer Society, Los Alamitos, 2005, pp. 53–62
[13] Ahlfors Q-regular spaces with arbitrary admitting weak Poincaré inequality, Geom. Funct. Anal., Volume 10 (2000) no. 1, pp. 111-123
[14] J. Lee, A. Naor, metrics on the Heisenberg group and the Goemans–Linial conjecture, Preprint, 2006
[15] Métriques de Carnot–Carathéodory et quasiisométries des espaces symétriques de rang un, Ann. of Math. (2), Volume 129 (1989) no. 1, pp. 1-60
[16] On the nonexistence of bi-Lipschitz parameterizations and geometric problems about -weights, Rev. Mat. Iberoamericana, Volume 12 (1996) no. 2, pp. 337-410
Cited by Sources:
Comments - Policy