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Voici les éléments 1 - 10 sur 437
- PublicationAccès libre
- PublicationMétadonnées seulementThe Haagerup property for measure preserving standard equivalence relations(2005)We define a notion of the Haagerup property for measure-preserving standard equivalence relations. Given such a relation R on X with finite invariant measure mu, we prove that R has the Haagerup property if and only if the associated finite von Neumann algebra L(R) (see J. Feldman and C. C. Moore. Ergodic equivalence relations, cohomology and von Neumann algebras II. Trans. Amer. Math. Soc. 234 (1977), 325-350) has relative property H in the sense of Popa with respect to its natural Cartan subalgebra L-infinity(X, mu). We also prove that if G is a countable group such that R = R-G has the Haagerup property and if R is ergodic, then G cannot have Kazhdan's property T.
- PublicationMétadonnées seulementNon-Properness of Amenable Actions on Graphs with Infinitely Many Ends(: World Scientific Pub Co Inc, 2006)
;Moon, Soyoung; ;Hawkes, TrevorLongobardi, Patrizia - PublicationAccès libreUpper bounds for Steklov eigenvalues of submanifolds in Euclidean space via the intersection index(2021-6-18)
; Gittins, Katie - PublicationMétadonnées seulementSome smooth Finsler deformations of hyperbolic surfaces(2009)
; ;Newberger, FlorenceVerovic, PatrickGiven a closed hyperbolic Riemannian surface, the aim of the present paper is to describe an explicit construction of smooth deformations of the hyperbolic metric into Finsler metrics that are not Riemannian and whose properties are such that the classical Riemannian results about entropy rigidity, marked length spectrum rigidity and boundary rigidity all fail to extend to the Finsler category. - PublicationAccès libreLusternik-Schnirelmann theory for fixed points of maps(2003)
;Rudyak, Yuli B. - PublicationMétadonnées seulementUniform stability of the Dirichlet spectrum for rough perturbations(2013-10-29)
; ; Iversen, Mette - PublicationMétadonnées seulementEigenvalue control for a Finsler--Laplace operator(2013-5-1)
;Barthelmé, Thomas - PublicationMétadonnées seulementExtremal g-invariant eigenvalues of the Laplacian of g-invariant metrics(2008-12-21)
; ;Dryden, Emily BEl Soufi, AhmadThe study of extremal properties of the spectrum often involves restricting the metrics under consideration. Motivated by the work of Abreu and Freitas in the case of the sphere S-2 endowed with S-1-invariant metrics, we consider the subsequence lambda(G)(k) of the spectrum of a Riemannian manifold M which corresponds to metrics and functions invariant under the action of a compact Lie group G. If. G has dimension at least 1, we show that the functional lambda(G)(k) admits no extremal metric under volume-preserving G-invariant deforma- tions. If, moreover, M has dimension at least three, then the functional lambda(G)(k) is unbounded when restricted to any conformal class of G-invariant metrics of fixed volume. As a special case of this, we can consider the standard 0(n)-action on S-n; however, if we also require the metric to be induced by an embedding of S-n in Rn+1, we get an optimal upper bound on lambda(G)(k). - PublicationMétadonnées seulementConjugacy growth series and languages in groups(2014)
; Hermiller, Susan