Conley pairs help in geometry, proving the Lusternik-Schnirelmann Theorem.
problem Proving the Lusternik-Schnirelmann Theorem in geometry.
method Using Conley pairs to implement the gradient flow proof of the Lusternik-Schnirelmann Theorem.
result Implemented the gradient flow proof of the Lusternik-Schnirelmann Theorem.
The paper proves a theorem linking convex body centroids and category theory.
problem Understanding centroids of sections of convex bodies.
method Lusternik-Schnirelmann category theory.
result At least n hyperplanes exist such that the center of mass of their intersection with a convex body lies on the boundary of the convex body.
We will provide a lower bound for the equivariant Lusternik-Schnirelmann category of an arbitrary proper action in terms of the stratification by orbit types, and an upper bound for proper polar actions in terms of the equivariant Lusternik-Schnirelmann category of its generalized Weyl group. As an application we repro…
The study finds the minimum number of critical points for functionals on Frechet spaces and Finsler manifolds.
problem Finding the minimum number of critical points for functionals on Frechet spaces and Finsler manifolds.
method Applying the Lusternik-Schnirelmann category to evaluate the minimal number of critical points for Keller Cc1-functionals on Frechet spaces and Finsler manifolds. result The minimal number of critical points is determined by the Lusternik-Schnirelmann category.
The study proves the existence of geodesics on reversible Finsler spheres.
problem Existence of closed geodesics on Finsler 2-spheres.
method Generalization of Grayson's curve shortening flow.
result Existence of three simple closed geodesics and infinitely many closed geodesics.
We define the LS-category cat_g by means of covers of a space by general subsets, and show that this definition coincides with the classical Lusternik-Schnirelmann category for compact metric ANR spaces. We apply this result to give short dimension theoretic proofs of the Grossman-Whitehead theorem and Dranishnikov's t…
We introduce the notion of Lusternik-Schnirelmann category for differentiable stacks and establish its relation with the groupoid Lusternik-Schnirelmann category for Lie groupoids.
New bounds on shortest geodesic loops on a sphere.
problem Finding shortest geodesic loops on a sphere.
method Analyzing geodesic loops starting and ending at a fixed point on a sphere.
result At any point on a sphere, there are at least two distinct geodesic loops whose lengths are bounded by 8d and 14d.
We prove the Arnold conjecture for closed symplectic manifolds with π2(M)=0 and $\cat M=\dim M$. Furthermore, we prove an analog of the Lusternik-Schnirelmann theorem for functions with ``generalized hyperbolicity'' property.
Formula proved for Lusternik-Schnirelmann category of connected sums of manifolds.
problem Calculating the Lusternik-Schnirelmann category for connected sums of manifolds.
method Used the Berstein-Hilton invariant to prove the formula.
result Proved the formula $\cat(M_1\sharp M_2)=\max\{\cat M_1, \cat M_2\}$ for closed manifolds.
The article applies Lusternik-Schnirelmann theory to establish lower bounds on critical points using sequential and parametrized topological complexity.
problem Establishing lower bounds on the number of critical points of functions using topological complexity.
method Applying Lusternik-Schnirelmann theory to sequential and parametrized topological complexity.
result Established various lower bounds on the number of critical points using sequential and parametrized topological complexity.
The minimal number of critical points is studied for smooth functions on closed manifolds.
problem Determining the minimal number of critical points for smooth functions on closed manifolds.
method Investigates cylindrical ball neighborhoods and exotic critical points, proving the conjecture for certain types of critical points.
result The minimal number of critical points is the same for smooth functions without exotic critical points on closed manifolds of dimension at least 6.
This paper extends Lusternik-Schnirelmann category to non-compact manifolds.
problem Extending Lusternik-Schnirelmann category to non-compact manifolds.
method Explanation and extension of Farber's results to non-compact manifolds.
result Farber's results hold equally well on non-compact manifolds, and new phenomena occur in gradient flows.
We prove that manifolds of Lusternik-Schnirelmann category 2 necessarily have free fundamental group. We thus settle a 1992 conjecture of Gomez-Larranaga and Gonzalez-Acuna, by generalizing their result in dimension 3, to all higher dimensions. We also obtain some general results on the relations between the fundamenta…
Study probabilistic category and complexity bounds, comparing with classical invariants.
problem Bounding classical category and complexity in probabilistic settings.
method Probabilistic Lusternik-Schnirelmann category and topological complexity computations.
result Established a universal upper bound in finite cases, contrasting with classical invariants.
We extend Lusternik-Schnirelmann theory to pairs (f,φ), where φ is a homotopy equivalence of a space X, f is a function on X which decreases along φ and (f,φ) satisfies a discrete analog of the Palais-Smale condition. The theory is carried out in an equivariant setting.
Surgery method proves category inequality for specific manifolds.
problem Proving category inequality for manifolds with given connectivity.
method Surgery approach to analyze normal maps and manifolds.
result Category of M is at least as large as N under given conditions. Topological complexity for closed 1-forms
problem Topological complexity for closed 1-forms
method Introduce and study a corresponding version of topological complexity
result Establish analogues of basic properties of ordinary topological complexity
New flow proves classical theorem on geodesic chords.
problem Existence of multiple orthogonal geodesic chords.
method Chord shortening flow as negative gradient of length functional.
result Convex chords not orthogonal shrink to points.
We prove that manifolds of Lusternik-Schnirelmann category 2 necessarily have free fundamental group. We thus settle a 1992 conjecture of Gomez-Larranaga and Gonzalez-Acuna, by generalizing their result in dimension 3, to all higher dimensions. We examine its ramifications in systolic topology, and provide a sufficient…
Study finds lower bounds for solutions on Riemannian orbifolds.
problem Finding solutions to nonlinear elliptic problems on Riemannian orbifolds.
method Employed the photography method to establish a lower bound.
result Lower bound for the number of solutions in terms of category.
New coarse LS-category introduced for groups and spaces.
problem Large-scale topological properties of groups and spaces.
method Introducing a coarse analog of Lusternik-Schnirelmann category for metric spaces.
result Established lower and upper bounds for geometrically finite and bicombable groups.
Let (M,g) be any closed Riemannianan manifold and (N,h) be a Riemannian manifold of constant positive scalar curvature. We prove that the Yamabe equation on the Riemannian product (M×N,g+δh) has at least Cat(M)+1 solutions for δ small enough, where Cat(M) denotes the Lusternik-Schnirelmann-categ…
The paper proves rigidity theorems for area widths of Riemannian manifolds.
problem Characterizing metrics on Riemannian manifolds using their area widths.
method Analyzing the volume spectrum and spherical area widths.
result Rigidity theorems for specific metrics on projective spaces.
We prove that the Lusternik-Schnirelmann category cat(M) of a closed symplectic manifold (M,ω) equals the dimension dim(M) provided that the symplectic cohomology class vanishes on the image of the Hurewicz homomorphism. This holds, in particular, when π2(M)=0. The Arnold conjecture asserts that the number of…
The study confirms a conjecture about critical points of smooth functions.
problem Understanding isolated critical points of smooth functions.
method Investigated cone-like, reasonable, and Rothe H hypothesis critical points.
result The conjecture holds true for certain critical points.
Study numerical invariants under retraction maps between topological spaces.
problem Understand behavior of invariants like cohomological dimensions under retractions.
method Introduced a notion of retraction and studied several numerical invariants.
result Proved inequalities between invariants hold under retractions.
Study on LS-category and topological complexity of connected sum manifolds.
problem Behavior of LS-category and topological complexity under connected sum operation.
method Analyzes the invariants LS-category and topological complexity for connected sum of manifolds.
result For orientable manifolds, $\cat(M\# N)=\max\{\cat M,\cat N\}$; for simply connected manifolds, $\TC (M\# N)\ge\max\{\TC M,\TC N\}$.
The topological complexity TC(X) is a numerical homotopy invariant of a topological space X which is motivated by robotics and is similar in spirit to the classical Lusternik-Schnirelmann category of X. Given a mechanical system with configuration space X, the invariant TC(X) measures the complexity of all possible mot…
The study finds multiple solutions for constant Q-curvature metrics.
problem Finding multiple metrics with constant Q-curvature.
method Proving subcritical equations have at least Cat(M) positive solutions.
result Proves existence of at least Cat(M) metrics with constant Q-curvature.
Study proves existence of closed geodesics on spheres and projective spaces.
problem Proving the existence of closed geodesics on Finsler metrics.
method Topological methods and Lusternik-Schnirelmann-type approach, using spherical complexities.
result Existence of multiple closed geodesics and upper bounds on their lengths.
New TC variant dTC better fits motion planning for some systems.
problem Improving motion planning for autonomous systems.
method Defined and computed new homotopy invariant dTC.
result dTC and dcat provide better motion planning solutions.
New invariants help find closed geodesics on curved spaces.
problem Finding closed geodesics on curved spaces.
method Constructing numerical homotopy invariants and applying them to functions on loop and sphere spaces.
result Proved new existence results for closed geodesics on Finsler manifolds.
Maps from 2-planes to projective spaces using quaternions and octonions.
problem Constructing maps between geometric spaces.
method Using quaternions and octonions, maps are constructed from Gr2(Rn) to RPk. result Maps induce isomorphisms at the fundamental group level and are submersions for certain values of n and k. The paper explores the topology and curvature of isoparametric families in spheres.
problem Investigating the topology and curvature of isoparametric families in spheres.
method The paper investigates the topology and curvature of isoparametric families in spheres using homotopy, homeomorphism, diffeomorphism types, parallelizability, and Lusternik-Schnirelmann category.
result The paper determines conditions for non-negative sectional curvatures and positive Ricci curvatures in isoparametric families.
In his work on singularities, expanders and topology of maps, Gromov showed, using isoperimetric inequalities in graded algebras, that every real valued map on the n-torus admits a fibre whose homological size is bounded below by some universal constant depending on n. He obtained similar estimates for maps with va…
We show that the geodesic period spectrum of a Riemannian 2-orbifold all of whose geodesics are closed depends, up to a constant, only on its orbifold topology and compute it. In the manifold case we recover the fact proved by Gromoll, Grove and Pries that all prime geodesics have the same length. In the appendix we pa…
The study finds conditions for nonmaximal topological complexity of manifolds with abelian fundamental groups.
problem Conditions for nonmaximal topological complexity of manifolds with abelian fundamental groups.
method Analyzes conditions and examples to generalize results on topological complexity and Lusternik-Schnirelmann category.
result Generalizes results on topological complexity and Lusternik-Schnirelmann category for manifolds with abelian fundamental groups.
We study the number of Darboux charts needed to cover a closed connected symplectic manifold (M,ω), and effectively estimate this number from below and from above in terms of the Lusternik--Schnirelmann category of M and the Gromov width of (M,ω).
Investigates spectral problems in Finsler geometry with novel dimension pairs.
problem Spectral problems in Finsler geometry due to nonlinearity of the Finsler-Laplacian operator.
method Introduced 'faithful dimension pairs' to define the spectrum of compact reversible Finsler metrics.
result Provided upper and lower bounds for eigenvalues, extending previous results.
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.
We show that the Lusternik-Schnirelmann category of the homotopy cofiber of the diagonal map for non-orientable surfaces equals three. Also, we prove that the topological complexity of non-orientable surfaces of genus >3 is four.
New bounds on triangulations of manifolds with non-free fundamental groups.
problem Finding lower bounds on the number of vertices in PL-triangulations of manifolds.
method Using fundamental group structure and Lusternik-Schnirelmann category theory.
result Every PL-triangulation of a d-dimensional manifold with non-free fundamental group has at least 3d+1 vertices. We show that the geometry of a Riemannian manifold (M,g) is sensitive to the apparently purely homotopy-theoretic invariant of M known as the Lusternik-Schnirelmann category, denoted cat_{LS}(M). Here we introduce a Riemannian analogue of cat_{LS}(M), called the systolic category of M. It is denoted cat_{sys}(M), and d…
We discuss homotopy properties of endpoint maps for affine control systems. We prove that these maps are Hurewicz fibrations with respect to some W1,p topology on the space of trajectories, for a certain p>1. We study critical points of geometric costs for these affine control systems, proving that if the base m…
Let S be a set of critical points of a smooth real-valued function on a closed manifold M. Generalizing a well-known result of Lusternik--Schnirelmann, Reeken~[R] proved that $\cat S \geq \cat M$. Here we prove a generalization of Reeken"s inequality for gradient-like flows on compact spaces.
Lower bounds on periodic Finsler billiard trajectories in convex hypersurfaces.
problem Estimating the number of periodic Finsler billiard trajectories.
method Morse and Lusternik-Schnirelmann theories applied to extremal polygons inscribed in a smooth closed hypersurface.
result For prime r≥3, the number of r-periodic Finsler billiard trajectories is not less than (r−1)(d−2)+1. We prove a new systolic volume lower bound for non-orientable n-manifolds, involving the stable 1-systole and the codimension 1 systole with coefficients in Z_2. As an application, we prove that Lusternik-Schnirelmann category and systolic category agree for non-orientable closed manifolds of dimension 3, extending our…