Study determines Borsuk-Ulam property for maps between torus and Klein bottle.
problem Determining maps with Borsuk-Ulam property between torus and Klein bottle.
method Analyzing homotopy classes of maps and using fundamental groups.
result Identifies specific homotopy classes of maps with Borsuk-Ulam property.
The paper connects sectional category and parametrized Borsuk-Ulam property for fibrations.
problem Parametrized Borsuk-Ulam property for fibrations.
method Investigation of sectional category connections and fibrations.
result The sectional category of q being larger than qp′ implies the parametrized Borsuk-Ulam property for the triple (p,τ;p′). In this paper we present a Kakutani type theorem that is equivalent to the Borsuk--Ulam theorem for manifolds.
Extends Borsuk-Ulam theorem with applications in sphere coverings and colorings.
problem Complexity bounds and structural insights for triangulated sphere mappings.
method Combinatorial labeling and order type analysis of finite point sets.
result New topological Hall theorem and generalizations of hypergraph Hall theorems.
New example solves topological dynamics problem.
problem Embedding compact metric space into cubical shift.
method Borsuk-Ulam theorem, p-adic completions, equivariant Sullivan conjecture.
result Existence of a compact metric space not embeddable into a cubical shift.
The paper generalizes the Borsuk-Ulam theorem to surfaces and cyclic actions.
problem Generalizing the Borsuk-Ulam theorem to surfaces and cyclic actions.
method Algebraic criterion involving braid groups and homology groups.
result Determines the Borsuk-Ulam property for maps from surfaces to R^2.
Let M be a closed, connected 3-manifold which admits Nil geometry, we determine all free involutions τ on M and the Borsuk-Ulam index of (M,τ).
We consider spaces with free involutions that satisfy the Borsuk - Ulam theorems (BUT-spaces). There are several equivalent definitions for BUT-spaces that can be considered as their properties. Our main technical tool is Yang's cohomological index.
Let M be a Seifert manifold which belongs to the geometry Flat. In this work we determine all the free involutions τ on M, and the Borsuk-Ulam indice of (M,τ).
Let M and N be topological spaces such that M admits a free involution $\τ$. A homotopy class β ∈ [M, N ] is said to have the Borsuk-Ulam property with respect to $\τ$ if for every representative map f : M → N of β, there exists a point x ∈ M such that f ($\τ$ (x)) = f (x). In the case where M i…
Study exact partition recovery with same-cluster oracle, bounded error.
problem Exact recovery of partitions with same-cluster oracle in adversarial error.
method Novel connection to correlation clustering, Rényi-Ulam framework, upper and lower bounds, randomized algorithm analysis, adaptivity-query complexity study.
result Upper and lower bounds on worst-case query complexity, expected performance bounds of randomized algorithm.
The paper proves no multiple equichordal points exist in convex bodies.
problem Existence of multiple equichordal points in convex bodies.
method Topological tools like the Borsuk-Ulam theorem and analysis of convex body properties.
result Nonexistence of multiple equichordal points in n-dimensional convex bodies for n≥2. Let M be a topological space that admits a free involution τ, and let N be a topological space. A homotopy class β∈[M,N] is said to have {\it the Borsuk-Ulam property with respect to τ} if for every representative map f:M→N of β, there exists a point x∈M such that f(τ(x))=f(x). In this …
Let (X, t, S) be a triple, where S is a compact, connected surface without boundary, and t is a free cellular involution on a CW-complex X. The triple (X, t, S) is said to satisfy the Borsuk-Ulam property if for every continuous map f:X-->S, there exists a point x belonging to X satisfying f(t(x))=f(x). In this paper, …
New theorem connects distant points and identical points on manifolds.
problem Continuous maps and distant points on manifolds.
method Qualitative extension of Hopf theorem, using topological 'distant' points.
result Existence of connected component containing both distant and identical points.
The paper studies self-Bäcklund curves in centroaffine geometry using elliptic functions.
problem Understanding self-Bäcklund curves in centroaffine geometry.
method Description of general properties and detailed analysis using elliptic functions.
result Provides a detailed description of self-Bäcklund centroaffine curves in terms of elliptic functions.
Thickenings of a metric space capture local geometric properties of the space. Here we exhibit applications of lower bounding the topology of thickenings of the circle and more generally the sphere. We explain interconnections with the geometry of circle actions on Euclidean space, the structure of zeros of trigonometr…
The paper studies which branched covers can be lifted to braided embeddings.
problem Which branched covers lift to braided embeddings?
method Analyzes conditions for liftability using Hansen's criterion and examples in different dimensions.
result Not all branched covers lift to braided embeddings; examples are provided in various dimensions.
The paper connects geometric and topological concepts to bound distances between metric spaces.
problem Bounding distances between metric spaces using Gromov-Hausdorff distance.
method Using Borsuk-Ulam theorems and Vietoris-Rips complexes, the paper obstructs the existence of certain continuous maps between complexes to bound discontinuities of functions.
result The paper provides new bounds on Gromov-Hausdorff distances between spheres of different dimensions.
We compute the rings H∗(N;F2) for N a closed Sol3-manifold and then determine the Borsuk-Ulam indices BU(N,φ) with φ=0 in H1(N;F2).
Bounds and constructions for Gromov-Hausdorff distance between spheres.
problem Calculating distances between spheres using Gromov-Hausdorff metric.
method Explicit constructions and topological ideas based on Borsuk-Ulam theorem.
result Lower bounds are tight for specific cases of sphere distances.
Let M be a manifold, V be a vector field on M, and B be a Banach space. For any fixed function f:M→B and any fixed complex number λ, we study Hyers-Ulam stability of the global differential equation Vy=λy+f.
We prove several new results around Gromov's waist theorem. We give a simple proof of Vaaler's theorem on sections of the unit cube using the Borsuk--Ulam--Crofton technique. We consider waists of real and complex projective spaces, flat tori, convex bodies in Euclidean space. We establish waist-type results in terms o…
The paper explores how to reduce classification tasks to optimization problems in Euclidean space.
problem Understanding the minimum dimension needed for reducing classification tasks to optimization problems.
method Developed a generalization of the Borsuk-Ulam Theorem to analyze the expressivity of reductions.
result The minimum Euclidean dimension required can be exponentially larger than the VC dimension, even for slightly non-trivial reductions.
The study connects projective codes to the distribution of zeros of odd maps.
problem Understanding the distribution of zeros of odd maps from spheres to Euclidean space.
method Using the topology of the space of probability measures on the sphere.
result Generalization of the Borsuk-Ulam theorem and its four consequences.
Introduces injective category number for continuous maps, linking classical and contemporary research.
problem Understanding conditions for a continuous map to be injective.
method Defines injective category number and examines its behavior under various operations.
result Provides a cohomological lower bound and expressions for injective category numbers in specific cases.
Proves existence of sentences to identify homeomorphic manifolds.
problem Identifying homeomorphic manifolds using group properties.
method Defines sentences in group language to match homeomorphic manifolds.
result Existence of sentences to distinguish homeomorphic manifolds.
Researchers create black holes isometric to extremal Reissner-Nordström.
problem Third law of black hole thermodynamics.
method Novel Ck characteristic gluing procedure and scalar field pulses. result Definitive disproof of the third law of black hole thermodynamics.
Tucker and Ky Fan's lemma are combinatorial analogs of the Borsuk-Ulam theorem (BUT). In 1996, Yu. A. Shashkin proved a version of Fan's lemma, which is a combinatorial analog of the odd mapping theorem (OMT). We consider generalizations of these lemmas for BUT-manifolds, i.e. for manifolds that satisfy BUT. Proofs rel…
The abstract discusses transversality for infinite dimensional manifolds.
problem Transversality for infinite dimensional Fréchet manifolds.
method Constructing degree of nonlinear Fredholm mappings using transversality results.
result Proof of rank theorem, invariance of domain theorem, and Bursuk-Ulam type theorem.
We introduce and study a new family of extensions for the Borsuk-Ulam and topological Radon type theorems. The defining idea for this new family is to replace requirements of the form `a subset that is large in some sense goes to a singleton' with requirements of the milder form `a subset that is large in some sense go…
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.
Let V and W be orthogonal representations of G with VG=WG={0}. Let S(V) be the sphere of V and f:S(V)→W be a G-equivariant mapping. We give an estimate for the dimension of the set Zf=f−1{0} in terms of dimV and dimW, if G is the torus Tk, or the p-torus $\ma…
Stability result for nearly isometric subspaces and Finsler surfaces.
problem Stability of normed spaces and Finsler surfaces under near-isometric conditions.
method Refined topological argument and explicit quantification using Banach-Mazur distance.
result A 2-dimensional surface with near-monochromatic Finsler metric is approximately Riemannian.
The width w of a curve γ in Euclidean space Rn is the infimum of the distances between all pairs of parallel hyperplanes which bound γ, while its inradius r is the supremum of the radii of all spheres which are contained in the convex hull of γ and are disjoint from γ. We use a mixture of topological and…
This paper is an expository account of the development of soliton mathematics, from its inception in famous numerical experiments of Fermi-Pasta-Ulam and Zabusky-Kruskal to the recent synthesis of Terng-Uhlenbeck (dg-ga/9707004) that explains hidden symmetries of soliton equations in terms of loop-groups acting by dres…
It is proved that for a product action of (Zp)k on a product of (mod p) homology spheres Nn1×...×Nnk, where all ni's are assumed to be odd if p is odd, and any continuous map f:Nn1×...×Nnk→Rm the set $A(f)=\{x\in N^{n_1}\times...\times N^{n_k}…
New family of measurable pseudo-Anosov maps on spheres.
problem Generalizing pseudo-Anosov maps to measurable ones.
method Continuous family of homeomorphisms on sphere, semi-conjugate to core tent map.
result Measurable pseudo-Anosov maps have invariant dense streamlines with uniform measures.
New quasimorphisms constructed for manifolds with negative curvature.
problem Building quasimorphisms on manifolds with negative curvature.
method Generalizing Barge and Ghys construction to Lie groups.
result Counterexamples to Kapovich and Fujiwara theorem for Lie groups.
Study of f-neighbors in Riemannian manifolds, proving infinite set of distances.
problem Exploring variations of Hopf theorem in Riemannian manifolds.
method Investigates continuous maps of compact Riemannian manifolds to Rm and introduces f-neighbors. result Set of distances realized as visual f-neighbors is infinite. The study applies wealth thermalization hypothesis to social networks and explains inequality.
problem Explains inequality in human society through wealth thermalization hypothesis.
method Uses Random Matrix Theory and social networks with nonlinear perturbation.
result Shows that wealth distribution follows Rayleigh-Jeans distribution, leading to inequality.
We survey the status of some decision problems for 3-manifolds and their fundamental groups. This includes the classical decision problems for finitely presented groups (Word Problem, Conjugacy Problem, Isomorphism Problem), and also the Homeomorphism Problem for 3-manifolds and the Membership Problem for 3-manifold gr…
Optimal transport reformulates multiple quantile hedging problem.
problem Multiple quantile hedging problem in incomplete markets.
method Reformulated as Monge optimal transport problem, introduced Kantorovitch version, proved no duality gap.
result Multiple quantile hedging problem can be seen as semi-discrete optimal transport problem.
Solves four problems related to circle families in the plane.
problem Four basic problems of circle families in the plane.
method Solves all four basic problems of circle families in the plane.
result All four basic problems are solved.
Solves four problems related to sphere families in 3D space.
problem Four basic problems of sphere families in Euclidean 3-space.
method Solves all four basic problems of sphere families in Euclidean 3-space.
result All four basic problems are solved.
The paper solves optimal control problems for various convex sets using convex trigonometry.
problem Optimal control problems with 2D convex compact sets.
method Using convex trigonometry to derive extremals for various problems.
result Geodesics in multiple sub-Finsler problems are derived.
This paper is a tutorial for eigenvalue and generalized eigenvalue problems. We first introduce eigenvalue problem, eigen-decomposition (spectral decomposition), and generalized eigenvalue problem. Then, we mention the optimization problems which yield to the eigenvalue and generalized eigenvalue problems. We also prov…
This paper solves the Christoffel problem in hyperbolic space and its equivalent on spheres.
problem Prescribing curvatures for convex hypersurfaces in hyperbolic space.
method Proving a full rank theorem to establish the existence of solutions.
result Existence of solutions to the Christoffel problem and its equivalent Nirenberg-Kazdan-Warner problem on spheres.