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Related papers: Isospectral Alexandrov Spaces

200 papers

We survey some aspects of the theory of noncommutative manifolds focusing on the noncommutative analogs of two-dimensional tori and low-dimensional spheres. We are particularly interested in those aspects of the theory that link the…

Quantum Algebra · Mathematics 2007-05-23 Jorge Plazas

We prove that Alexandrov's conjecture relating the area and diameter of a convex surface holds for the surface of a general ellipsoid. This is a direct consequence of a more general result which estimates the deviation from the optimal…

Differential Geometry · Mathematics 2015-12-04 Pedro Freitas , David Krejcirik

In this paper we consider nonnegatively curved finite dimensional Alexandrov spaces with a non-collapsing condition, i.e., such that unit balls have volumes uniformly bounded from below away from zero. We study the relation between the…

Differential Geometry · Mathematics 2025-04-01 Gioacchino Antonelli , Marco Pozzetta

An orbifold version of Bogomolov decomposition theorem is established for compact K\"ahler spaces with quotient singularities and first Chern class zero.The proof is a direct adaptation of the classical smooth case, using Ricci-flat…

Algebraic Geometry · Mathematics 2007-05-23 Frederic Campana

We consider two natural Lagrangian intersection problems in the context of symplectic toric manifolds: displaceability of torus orbits and of a torus orbit with the real part of the toric manifold. Our remarks address the fact that one can…

Symplectic Geometry · Mathematics 2012-01-18 Miguel Abreu , Leonardo Macarini

We relate the recently defined spectral torsion with the algebraic torsion of noncommutative differential calculi on the example of the almost-commutative geometry of the product of a closed oriented Riemannian spin manifold $M$ with the…

Quantum Algebra · Mathematics 2025-02-04 Ludwik Dąbrowski , Yang Liu , Sugato Mukhopadhyay

The K-rings of non-singular complex pro jective varieties as well as quasi- toric manifolds were described in terms of generators and relations in an earlier work of the author with V. Uma. In this paper we obtain a similar description for…

Algebraic Topology · Mathematics 2007-07-12 Parameswaran Sankaran

In the present article we introduce and study a class of topological reflection spaces that we call Kac-Moody symmetric spaces. These generalize Riemannian symmetric spaces of non-compact type. We observe that in a non-spherical Kac-Moody…

Group Theory · Mathematics 2019-05-03 Walter Freyn , Tobias Hartnick , Max Horn , Ralf Köhl

The well known equivalence between preorders and Alexandrov spaces is extended to an equivalence between arbitrary topological spaces and spatial fibrous preorders, a new notion to be introduced.

Category Theory · Mathematics 2013-08-01 N. Martins-Ferreira

We define a compactification of symmetric spaces of noncompact type, seen as spaces of isometry classes of marked lattices, analogous to the Thurston compactification of the Teichm\"uller space, and we show that it is equivariantly…

Geometric Topology · Mathematics 2011-05-11 Thomas Haettel

We first show that a Laplace isospectral family of Riemannian orbifolds, satisfying a lower Ricci curvature bound, contains orbifolds with points of only finitely many isotropy types. If we restrict our attention to orbifolds with only…

Spectral Theory · Mathematics 2009-09-29 Elizabeth Stanhope

An important question with a rich history is the extent to which the symplectic category is larger than the Kaehler category. Many interesting examples of non-Kaehler symplectic manifolds have been constructed. However, sufficiently large…

dg-ga · Mathematics 2008-02-03 Susan Tolman

We study branched covering spaces in several contexts, proving that under suitable circumstances the cover satisfies the same upper curvature bounds as the base space. The first context is of a branched cover of an arbitrary metric space…

Differential Geometry · Mathematics 2007-05-23 Daniel Allcock

In a recent paper Garoufalidis and Reid constructed pairs of 1-cusped hyperbolic 3-manifolds which are isospectral but not isometric. In this paper we extend this work to the multi-cusped setting by constructing isospectral but not…

Geometric Topology · Mathematics 2023-07-20 Benjamin Linowitz

With the goal of solving optimisation problems on non-Riemannian manifolds, such as geometrical surfaces with sharp edges, we develop and prove the convergence of a forward-backward method in Alexandrov spaces with curvature bounded both…

Optimization and Control · Mathematics 2026-04-03 Heikki von Koch , Tuomo Valkonen

The equivariant Gromov--Hausdorff convergence of metric spaces is studied. Where all isometry groups under consideration are compact Lie, it is shown that an upper bound on the dimension of the group guarantees that the convergence is by…

Metric Geometry · Mathematics 2020-01-23 John Harvey

A number of questions related to the length spectrum of surfaces are discussed and in particular the existence of pairs of surfaces which though not isometric are isospectral. Here by isospectral we mean that a pair of bodies have the same…

Geometric Topology · Mathematics 2023-08-24 Hidetoshi Masai , Greg McShane

S. Donaldson introduced a metric on the space of volume forms, with fixed total volume on any compact Riemmanian manifold. With this metric, the space of volume forms formally has non-positive curvature. The geodesic equation is a fully…

Differential Geometry · Mathematics 2010-04-16 Xiuxiong Chen , Weiyong He

We classify tuples of (not necessarily commuting) isometries that admit von Neumann-Wold decomposition. We introduce the notion of twisted isometries for tuples of isometries and prove the existence of orthogonal decomposition for such…

Functional Analysis · Mathematics 2022-09-29 Narayan Rakshit , Jaydeb Sarkar , Mansi Suryawanshi

In the previous work [35], the second and third authors established a Bochner type formula on Alexandrov spaces. The purpose of this paper is to give some applications of the Bochner type formula. Firstly, we extend the sharp lower bound…

Differential Geometry · Mathematics 2012-05-29 Zhongmin Qian , Hui-Chun Zhang , Xi-Ping Zhu