Proves linear extension of isometries in smooth 2D Banach spaces.
problem Linear extension of isometries in absolutely smooth 2D Banach spaces.
method Analyzes isometries between unit spheres of smooth Banach spaces.
result Any isometry extends to a linear isometry of Banach spaces.
Study introduces combinatorial criterion for quasi-isometry groups of Euclidean spaces.
problem Determining quasi-isometries of Euclidean spaces.
method Introduces PLδ-homeomorphisms and combinatorial criterion using vertices and edges of simplicial structures. result The center of the quasi-isometry group QI(Rn) is trivial. The geometry of conjugation is mapped within Euclidean isometry groups.
problem Understanding conjugacy classes and their transformations in Euclidean groups.
method Geometric description of conjugacy classes and sets of conjugating elements based on linearizations.
result The conjugacy classes and sets of conjugating elements are described by the move-set and fix-set of linearizations.
Study on holomorphic isometries between complex domains, revealing geometric properties.
problem Characterizing holomorphic isometries between bounded symmetric domains.
method Analyzing holomorphic isometries between complex unit ball and other bounded symmetric domains, using classical results for complex-analytic subvarieties of Stein manifolds.
result Images of holomorphic isometries have specific geometric properties, including intersections with affine-linear subspaces.
In this paper we study isometry-invariant Finsler metrics on inner product spaces over R or C, i.e. the Finsler metrics which do not change under the action of all isometries of the inner product space. We give a new proof of the analytic description of all such metrics. In this article the most g…
Conditions for polynomial to be isometry of lattice, answering Hasse principles.
problem Conditions for integral polynomials to be characteristic polynomials of isometries of lattices.
method Necessary and sufficient conditions derived from lattice isometries and Hasse principles.
result Proved a Hasse principle for signatures of knots.
Teichmüller space rigidity proven for Thurston metric.
problem Understanding isometries in Teichmüller space with Thurston metric.
method Analyzing R-linear surjective isometries between cotangent spaces. result Every isometry between hyperbolic surfaces induces an isometry in Teichmüller space.
We consider sub-Riemannian spaces admitting an isometry group that is maximal in the sense that any linear isometry between the horizontal tangent spaces is realized by a global isometry. We will show that these spaces have a canonical choice of partial connection on their horizontal bundle, which is determined by isom…
The article proves isometry theorems for specific types of manifolds.
problem Investigating properties of Cartan-Hadamard manifolds and related solitons.
method Analyzing steady, gradient shrinking, and expanding Ricci solitons.
result Specific manifolds are isometric to Euclidean space under certain conditions.
New analysis proves sketching operators' RIP guarantees for mixture models without importance sampling.
problem Proving sketching operators' Restricted Isometry Property (RIP) for mixture models without assuming importance sampling.
method Proposed alternative analysis based on new deterministic bounds and concentration inequalities.
result Theoretical guarantees for sketching operators without importance sampling.
Let G be a countable group which acts by isometries on a separable, but not necessarily proper, Gromov hyperbolic space X. We say the action of G is weakly hyperbolic if G contains two independent hyperbolic isometries. We show that a random walk on such G converges to the Gromov boundary almost surely. We apply the co…
The paper classifies groups that can be isometry groups of infinite-genus hyperbolic surfaces.
problem Which groups can be realized as isometry groups of infinite-genus hyperbolic surfaces?
method Classification of isometry groups for infinite-genus 2-manifolds with no planar ends.
result There is an uncountable class of 2-manifolds where every countable group can be realized as an isometry group.
The paper studies MCF solutions on the Heisenberg group and finds linear affine motion functions.
problem Investigating mean curvature flow soliton solutions on the Heisenberg group.
method Analyzes solutions generated by isometries and proves motion functions are linear.
result Function describing motion is always a linear affine function.
It is known that the order of a finite group of diffeomorphisms of a 3-dimensional handlebody of genus g > 1 is bounded by the linear polynomial 12(g-1), and that the order of a finite group of diffeomorphisms of a 4-dimensional handlebody (or equivalently, of its boundary 3-manifold), faithful on the fundamental group…
We characterize helix surfaces (constant angle surfaces) in the special linear group SL(2,)˚. In particular, we give an explicit local description of these surfaces in terms of a suitable curve and a 1-parameter family of isometries of SL(2,)˚.
Deep 3D models are vulnerable to isometry transformations under adversarial attacks.
problem Vulnerability of deep 3D models to isometry transformations under adversarial attacks.
method Developed a black-box attack with success rate over 95% and a novel white-box attack framework.
result Deep 3D models are extremely vulnerable to isometry transformations under adversarial attacks.
The paper proves manifold isometries for certain gradient Ricci solitons.
problem Characterizing isometry of gradient shrinking Ricci solitons.
method Analyzing volume growth, scalar curvature, and potential function subharmonicity.
result Gradient shrinking Ricci solitons with specific properties are isometric to spheres or other specific manifolds.
Given an affine isometry of R3 with hyperbolic linear part, its Margulis invariant measures signed Lorentzian displacement along an invariant spacelike line. In order for a group generated by hyperbolic isometries to act properly on R3, the sign of the Margulis invariant must be constant over the group. We show…
This note explores norms beyond ultrametric inequalities in non-Archimedean analysis.
problem Analyzing norms beyond ultrametric inequalities in non-Archimedean analysis.
method Characterization of isometries between finite-dimensional spaces with a specific norm.
result Characterization of isometries between finite-dimensional linear spaces over a valued field.
Maps close to isometries on Riemannian manifolds are close to isometries.
problem Understanding the rigidity of maps on Riemannian manifolds.
method Optimal linear estimate using Sobolev maps, weak Riemannian Piola identity, harmonic map heat flow, and linearization.
result Optimal rigidity estimate for maps of a compact Riemannian manifold to itself.
The paper proves conjectures about Minkowski norms with specific symmetry groups.
problem Proving conjectures about Minkowski norms with certain symmetries.
method Analyzing isometries of the Hessian metric for Minkowski norms invariant under SO(k)imesSO(n−k). result Proves Laugwitz and Landsberg Unicorn conjectures for Minkowski norms with the specified symmetry.
We consider various notions of strains; quantitative measures for the deviation of a linear transformation from an isometry. The main approach, which is motivated by physical applications and follows the work of Patrizio Neff and co-workers , is to select a Riemannian metric on GLn, and use its induced geodes…
Based on the work of Adams and Stuck as well as on the work of Zeghib, we classify the Lie groups which can act isometrically and locally effectively on Lorentzian manifolds of finite volume. In the case that the corresponding Lie algebra contains a direct summand isomorphic to the two-dimensional special linear algebr…
It is well known that the initialization of weights in deep neural networks can have a dramatic impact on learning speed. For example, ensuring the mean squared singular value of a network's input-output Jacobian is O(1) is essential for avoiding the exponential vanishing or explosion of gradients. The stronger condi…
We study general linear perturbations of a class of 4d real-dimensional hyperkahler manifolds obtainable by the (generalized) Legendre transform method. Using twistor methods, we show that deformations can be encoded in a set of holomorphic functions of 2d+1 variables, as opposed to the functions of d+1 variables contr…
Paper proves sufficient conditions for tensor recovery using t-RIP with random measurements.
problem Establish robust recovery guarantees for low-tubal-rank tensors.
method Probabilistic arguments and random sub-Gaussian distributions to ensure t-RIP conditions.
result Minimal number of linear measurements nearly optimal for tensor recovery.
Random walks on hyperbolic spaces show linear growth in translation lengths.
problem Investigate the growth of translation lengths in random walks on hyperbolic spaces.
method Prove linear growth without moment conditions and apply to Teichmüller spaces.
result Linear growth of translation lengths in random walks on hyperbolic spaces.
Isometry regularizer improves autoencoder performance on manifold learning.
problem Bad generalization in autoencoders, especially extrinsic and intrinsic issues.
method Introduces an isometry regularizer that encourages the decoder to be an isometry and the encoder to be its pseudo-inverse.
result Isometry regularizer leads to better generalization and useful low-dimensional data representations.
Being E a vector space with inner product and S the sphere of E, will be given a demonstration that every application of the sphere S itself it such that preserve inner product is the restriction of a linear isometry in E.
The paper studies cohomogeneity one actions on pseudo-Euclidean space and identifies unique orbit structures.
problem Characterizing cohomogeneity one actions on pseudo-Euclidean spaces.
method Analyzing isometric linear actions of subgroups of the isometry group of Rp,q. result Identified unique orbit structures of cohomogeneity one actions on Rp,q. Hexagon grid patterns emerge from conformal isometry in grid cell neural networks.
problem Understanding the algebraic, geometric, and topological properties of grid cells.
method Investigating recurrent neural network models of grid cells, focusing on Lie group and Lie algebra representations, conformal isometry, and hexagon periodic patterns.
result Conformal isometry leads to hexagon periodic patterns in grid cell responses and accurate path integration.
We give an analytical proof of the Poincare-type inequalities for widths of geodesic homotopies between equivariant maps valued in Hadamard metric spaces. As an application we obtain a linear bound for the length of an element conjugating two finite lists in a group acting on an Hadamard space.
The study classifies Heintze groups up to isometry and quasi-isometry in low dimensions.
problem Classifying Heintze groups up to isometry and quasi-isometry in low dimensions.
method Analyzing quasi-isometries and isometries of Heintze groups, applying existing tools to groups of dimension 4 and 5.
result Complete classification of simply connected solvable groups in dimension 4 and groups of polynomial growth in dimension 5 up to isometry.
Sign-RIP improves robust low-rank matrix recovery by preserving norms even with corrupted measurements.
problem Robust low-rank matrix recovery in the presence of corrupted measurements.
method Proposed Sign-RIP, a robust restricted isometry property.
result Sign-RIP guarantees uniform convergence of subdifferentials in robust low-rank matrix recovery.
A surface in hyperbolic space $\h^3$ invariant by a group of parabolic isometries is called a parabolic surface. In this paper we investigate parabolic surfaces of $\h^3$ that satisfy a linear Weingarten relation of the form aκ1+bκ2=c or aH+bK=c, where $a,b,c\in \r$ and, as usual, κi are the principal curvatur…
In 1995, S. Adams and G. Stuck as well as A. Zeghib independently provided a classification of non-compact Lie groups which can act isometrically and locally effectively on compact Lorentzian manifolds. In the case that the corresponding Lie algebra contains a direct summand isomorphic to the two-dimensional special li…
Orthogonal initialization does not speed up training in ultra-wide neural networks.
problem Exploring the effect of orthogonal initialization on training speed in deep neural networks.
method Study of neural tangent kernel dynamics in FCNs and CNNs with orthogonal initialization.
result The NTK of orthogonally-initialized networks remains constant during training, suggesting no speedup in the NTK regime.
Linear invariants of complex manifolds preserved by biholomorphisms.
problem Identifying biholomorphic mappings between complex manifolds using holomorphic function spaces.
method Proving biholomorphic equivalence of domains via linear isometries of Lp-integrable holomorphic functions. result Linear isometries between Ap spaces imply biholomorphic equivalence of domains, with conditions on p and domain properties. Differential structure on partial isometries over Grassmannian constructed.
problem No specific problem stated; abstract focuses on method and result.
method Construction of differential structure on partial isometries over restricted Grassmannian.
result Set of partial isometries over restricted Grassmannian becomes a Banach Lie groupoid.
Let HHn denote the n-dimensional quaternionic hyperbolic space. The linear group Sp(n,1) acts by the isometries of HHn. A subgroup G of Sp(n,1) is called \emph{Zariski dense} if it does not fix a point on ${{\bf H}_{\mathbb H}}^n \cup \partial {{\bf H}_…
Many important applications, including signal reconstruction, parameter estimation, and signal processing in a compressed domain, rely on a low-dimensional representation of the dataset that preserves {\em all} pairwise distances between the data points and leverages the inherent geometric structure that is typically p…
In this paper we review some author's results about Weingarten surfaces in Euclidean space $\r^3$ and hyperbolic space $\h^3$. We stress here in the search of examples of linear Weingarten surfaces that satisfy a certain geometric property. First, we consider Weingarten surfaces in $\r^3$ that are foliated by circles, …
Lifts isometries in orbit spaces for compact groups.
problem Isometries in orbit spaces of compact groups.
method Equivariant isometry of original Euclidean space.
result Simple formula for connected component of isometry group.
Let F=R, C or H. Let HFn denote the n-dimensional F-hyperbolic space. Let U(n,1;F) be the linear group that acts by the isometries. A subgroup G of U(n,1;F) is called \emph{Zariski dense} if it does not fix a point…
Sharp stability of isometries on Heisenberg group proven.
problem Quantitative stability of isometries on the Heisenberg group.
method Proving quasi-isometries close to isometries with specific closeness orders.
result Quasi-isometries of Heisenberg group are close to isometries with specific closeness orders.
Study reveals structure of isometry group for specific manifolds.
problem Understanding the isometry group of non-compact, homogeneous manifolds.
method Analyzes non-compact, homogeneous manifolds with immortal Ricci flows.
result Establishes structure result for isometry group.
Quantum isometry groups exist for certain metric spaces.
problem Existence of quantum isometry groups for specific metric spaces.
method Proved existence for geodesic metrics and uniformly distributed measure spaces.
result Quantum isometry groups are classical (commutative) for Riemannian manifolds.
Study finds all isometries for specific Lie groups.
problem Identifying isometry groups in nonunimodular Lie groups.
method Examined left-invariant Riemannian metrics on Lie groups of dimension four.
result Determined full group of isometries for each metric.