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Related papers: On the Blaschke's Conjecture

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It is known that if $M$ is a finite-dimensional Banach space, or a strictly convex space, or the space $\ell_1$, then every non-expansive bijection $F: B_M \to B_M$ is an isometry. We extend these results to non-expansive bijections $F: B_E…

Functional Analysis · Mathematics 2018-07-16 Olesia Zavarzina

Let $M$ be a graph manifold such that each piece of its JSJ decomposition has the $\Bbb H^2 \times \Bbb R$ geometry. Assume that the pieces are glued by isometries. Then, there exists a complete Riemannian metric on $\Bbb R \times M$ which…

Differential Geometry · Mathematics 2020-11-18 Koji Fujiwara , Takashi Shioya

Mahler's conjecture asks whether the cube is a minimizer for the volume product of a body and its polar in the class of symmetric convex bodies in R^n. The corresponding inequality to the conjecture is sometimes called the the reverse…

Metric Geometry · Mathematics 2013-02-26 Jaegil Kim , Artem Zvavitch

The Rolling Ball Theorem asserts that given a convex body K in Euclidean space and having a smooth surface bd(K) with all principal curvatures not exceeding c>0 at all boundary points, K necessarily has the property that to each boundary…

Differential Geometry · Mathematics 2009-03-30 Sz. Gy. Re've'sz

Motivated by a dictionary between polynomials and finite Blaschke products, we study both Smale's mean value conjecture and its dual conjecture for finite Blaschke products in this paper. Our result on the dual conjecture for finite…

Complex Variables · Mathematics 2016-09-02 Tuen-Wai Ng , Yongquan Zhang

We prove that if the classical Baum-Connes conjecture in complex K-theory is true (for a given discrete group G), then the conjecture is also true in the real case (for the same group G). The essential ingredients of the proof are the…

Operator Algebras · Mathematics 2016-09-07 Paul Baum , Max Karoubi

We prove that the Lusternik-Schnirelmann category $cat(M)$ of a closed symplectic manifold $(M, \omega)$ equals the dimension $dim(M)$ provided that the symplectic cohomology class vanishes on the image of the Hurewicz homomorphism. This…

dg-ga · Mathematics 2008-02-03 Yuli B. Rudyak , John Oprea

We consider the following generalisation of a well-known problem in Riemannian geometry: When is a smooth real-valued function s on a given compact n-dimensional manifold M (with or without boundary) the scalar curvature of some smooth…

Differential Geometry · Mathematics 2007-05-23 Marc Nardmann

The critical point equation arises as a critical point of the total scalar curvature functional defined on the space of constant scalar curvature metrics of a unit volume on a compact manifold. In this equation, there exists a function $f$…

Differential Geometry · Mathematics 2021-03-30 Seungsu Hwang , Gabjin Yun

In the biharmonic submanifolds theory there is a generalized Chen's conjecture which states that biharmonic submanifolds in a Riemannian manifold with non-positive sectional curvature must be minimal. This conjecture turned out false by a…

Differential Geometry · Mathematics 2014-05-30 Yong Luo

We describe an isomorphism of categories conjectured by Kontsevich. If $M$ and $\widetilde{M}$ are mirror pairs then the conjectural equivalence is between the derived category of coherent sheaves on $M$ and a suitable version of Fukaya's…

Algebraic Geometry · Mathematics 2008-11-26 Alexander Polishchuk , Eric Zaslow

We present a spherical version of the theorem of Blaschke that every body of constant width $w < \frac{\pi}{2}$ can be approximated as well as we wish in the sense of the Hausdorff distance by a body of constant width $w$ whose boundary…

Metric Geometry · Mathematics 2021-06-17 Marek Lassak

A submanifold $M$ of a Euclidean $m$-space is said to be biharmonic if $\Delta \overrightarrow H=0$ holds identically, where $\overrightarrow H$ is the mean curvature vector field and $\Delta$ is the Laplacian on $M$. In 1991, the author…

Differential Geometry · Mathematics 2013-07-16 Bang-Yen Chen

Let $M^4$ be a closed immersed minimal hypersurface with constant squared length of the second fundamental form $S$ and constant 3-mean curvature $H_3$ in $\mathbb{S}^{5}$. If $H_3^2\leq \frac{1}{2}.$ and Gauss-Kronecker curvature $K_M$…

Differential Geometry · Mathematics 2022-10-14 Fagui Li

In this paper, we begin by constructing global linear maps on (n-2)-dimensional subspaces, derived from the local continuity of linear transformations among central sections of a convex body. Using these linear maps, we subsequently…

Functional Analysis · Mathematics 2026-04-07 Ning Zhang

We explore the notion of m-intermediate Ricci curvature assumption introduced by Brendle-Hirsch-Johne further. If a manifold has non-negative m-intermediate Ricci curvature and stable weighted slicing of order m-1, then the last slice has…

Differential Geometry · Mathematics 2025-10-14 Yujie Wu

Let X be a complex surface with no nontrivial 2-forms. Then we show that Bloch's conjecture is true (i.e. the Albanese map in this case is injective) if and only if any homologically trivial idempotent in the ring of correspondences…

Algebraic Geometry · Mathematics 2007-05-23 Morihiko Saito

Given a real, twisted Dirac structure $L$ on a smooth manifold $M$, and a closed embedded submanifold $N\subseteq M$ of codimension $>1$, we characterise when $L$ lifts to a smooth, twisted Dirac structure on the real projective blowup of…

Symplectic Geometry · Mathematics 2025-06-19 Ioan Marcut , Andreas Schüßler , Marco Zambon

We prove two rigidity theorems for maps between Riemannian manifolds. First, we prove that a Lipschitz map $f:M\to N$ between two oriented Riemannian manifolds, whose differential is almost everywhere an orientation-preserving isometry, is…

Differential Geometry · Mathematics 2019-01-23 Raz Kupferman , Cy Maor , Asaf Shachar

We show that for every complete metric space $M$ there exists another complete metric space $N$ of the same density character such that the curve-flat quotient of $N$ is isometric to $M$. Moreover, we show that if $M$ is compact and…

Metric Geometry · Mathematics 2026-03-23 Jaan Kristjan Kaasik , Andrés Quilis