Estimates geodesics on surfaces without conjugate points.
problem Counting geodesics on surfaces without conjugate points.
method Margulis-type asymptotic estimates.
result Asymptotic estimates for geodesics on surfaces.
New manifolds found without interior conjugate points.
problem Existence of interior conjugate points in hyperbolic manifolds.
method Construction of non-trapping asymptotically hyperbolic manifolds.
result Found manifolds without interior conjugate points.
Study Price inequalities and Betti number growth on specific manifolds.
problem Understanding the asymptotic behavior of Betti numbers on manifolds without conjugate points.
method Derive Price inequalities for harmonic forms, use techniques for non-positive sectional curvature, and apply to Betti number growth.
result Prove strengthened Price inequalities and give vanishing results for L2-Betti numbers. In this short note, we prove that the usual Θ function on a Riemannian manifold without conjugate points is uniformly bounded from below. This extends a result of Green in two dimensions. This elementary lemma implies that the Bérard remainder in the Weyl law is valid for a manifold without conjugate points, without …
We show that in the fundamental groups of closed manifolds without conjugate points centralizers of all elements virtually split.
The study examines continuous mean curvature functions on manifolds without conjugate points.
problem Understanding properties of manifolds with specific curvature functions.
method Analyzing simply connected Riemannian manifolds with continuous horospherical mean curvature functions.
result Compact rank one manifolds without conjugate points are locally symmetric spaces of negative curvature.
Condition for Anosov flows on non-compact manifolds without conjugate points.
problem Conditions for Anosov flows on non-compact manifolds.
method Formulated a condition for complete, connected and non-compact Riemannian manifolds.
result No conjugate points in geodesic flow if Anosov.
Study geodesic flows on hyperbolic manifolds without conjugate points, proving unique measure of maximal entropy.
problem Proving uniqueness of measure of maximal entropy for geodesic flows on specific manifolds.
method Analyzing geodesic flows on closed Riemannian manifolds without conjugate points, using properties of Gromov hyperbolic and residually finite groups.
result Proves geodesic flow has a unique measure of maximal entropy under appropriate assumptions.
Locally extremal geodesic loops are closed geodesics in Riemannian manifolds.
problem Characterizing geodesic loops in Riemannian manifolds.
method Analyzing properties of geodesic loops and their conjugate points.
result Locally extremal non-self-conjugate geodesic loops are closed geodesics.
The paper connects geodesic flows and limit sets on visibility manifolds.
problem Understanding dynamics and ergodic properties on non-compact visibility manifolds.
method Analyzing geodesic flows and Patterson-Sullivan measures on visibility manifolds without conjugate points.
result The positivity of the Patterson-Sullivan measure of the Myrberg limit set is equivalent to the conservativity of the geodesic flow.
Study equilibrium measures on manifolds without conjugate points with visibility covering.
problem Uniqueness and properties of equilibrium measures on manifolds without conjugate points.
method Analysis of geodesic flows, study of equilibrium measures, ergodic properties, and pressure gap.
result Equilibrium measures satisfy a weak pressure gap under certain conditions.
Study ergodic properties of geodesic flows on specific manifolds without conjugate points.
problem Ergodic properties of geodesic flows on uniform visibility manifolds without conjugate points.
method Comprehensive study including geometric properties, entropy gap assumption, and symbolic approach.
result Geodesic flow is ergodic with respect to Liouville measure under certain conditions.
Euclidean metrics without conjugate points are proven to be flat.
problem Proving the flatness of metrics without conjugate points.
method Analyzing asymptotically Euclidean metrics.
result Asymptotically Euclidean metrics without conjugate points are isometric to the Euclidean metric.
Geodesic flows on specific manifolds are structurally stable.
problem Stability of geodesic flows on compact manifolds without conjugate points.
method Analyzing the C∞ compact manifold (M,g) with quasi-convex universal covering and divergent geodesic rays. result Proved the C1-stability conjecture for geodesic flows of compact manifolds. New examples of stable Lorentzian surfaces without conjugate points are found.
problem Existence and stability of Lorentzian surfaces without conjugate points.
method Study of new examples and stability among Lorentzian metrics with a Killing field.
result Obtained a new obstruction and proved stability of Clifton-Pohl torus and some examples.
Study non-convex manifolds' rigidity properties without convexity assumption.
problem Rigidity properties of non-convex manifolds.
method Analyzes boundary and lens rigidity on non-convex domains, proving rigidity for simply connected and non-trapping surfaces.
result Injectivity of X-ray transform on tensors for non-convex boundaries and non-trapping surfaces.
Geodesic flows on compact manifolds without conjugate points are shown to have a unique measure of maximal entropy.
problem Analyzing geodesic flows on compact manifolds without conjugate points and with visibility universal covering.
method Using topological mixing, local product structure, and properties of geodesic flows, the authors prove the existence of an expansive factor and uniqueness of measure of maximal entropy.
result The geodesic flow on compact manifolds without conjugate points has a unique measure of maximal entropy.
The paper solves the Dirichlet problem at infinity and defines Poisson boundaries for certain manifolds.
problem Existence of bounded harmonic functions on manifolds without conjugate points.
method Investigation of harmonic extensions and Poisson boundaries for specific types of manifolds.
result Harmonic extensions and Poisson boundaries defined for rank 1 manifolds without focal points.
We prove flatness of complete Riemannian planes and cylinders without conjugate points under optimal conditions on the area growth.
We show that given a point on a Finsler surface, one can always find a neighborhood of the point and isometrically embed this neighborhood into a Finsler torus without conjugate points.
Study light ray transform on Lorentzian manifolds without conjugate points.
problem Recovering spacelike singularities from weighted light ray transforms.
method Fourier Integral Operator analysis and filtered back-projection.
result Recovery of spacelike singularities from weighted light ray transforms without conjugate points.
Geodesic flows on certain surfaces are shown to be semi-conjugate to expansive flows.
problem Understanding geodesic flows on compact surfaces without conjugate points.
method Time-preserving semi-conjugation to a continuous expansive flow.
result Geodesic flows on compact surfaces without conjugate points of genus > 1 have a unique measure of maximal entropy.
Let Wn be the class of C∞ complete simply connected n−dimensional manifolds without conjugate points. The hyperbolic space as well as Euclidean space are good examples of such manifolds. Let and let A be a subset of W. This article aims at characterization and bu…
In this paper, we are interested in the location of conjugate points along a geodesic in the volumorphism group of a compact three-dimensional manifold without boundary (the configuration space of an ideal fluid). As shown in the author's previous work, these are typically pathological, i.e., they can occur in clusters…
The paper counts geodesic loops on surfaces without conjugate points.
problem Counting geodesic loops on surfaces of genus at least 2 without conjugate points.
method Proves asymptotic estimates for closed geodesic loops on compact surfaces with no conjugate points.
result Generalizes classical counting results and sector theorems for surfaces of strictly negative curvature.
Let (M,g) be a complete, simply connected Riemannian manifold of dimension 3 without conjugate points. We show that M is a flat manifold, provided M is asymptotically harmonic of constant h=0.
Global rigidity theorem for metrics on Σ×S1 without conjugate points.
problem Classifying metrics without conjugate points on Σ×S1.
method Two independent proofs: Busemann functions and Riccati equation, curvature operator analysis.
result Metrics on Σ×S1 without conjugate points are Riemannian products.
Unique entropy measure found for geodesic flows on certain surfaces.
problem Finding a unique measure of maximal entropy for geodesic flows.
method Analyzing geodesic flows on surfaces without conjugate points.
result Proved existence of a unique measure of maximal entropy for geodesic flows on certain surfaces.
Let (M,g) be a complete, simply connected Riemannian manifold of dimension 3 without conjugate points. We show that M is a hyperbolic manifold of constant sectional curvature, provided M is asymptotically harmonic of constant h > 0.
We study the geodesic X-ray transform IΓ of tensor fields on a compact Riemannian manifold M with non-necessarily convex boundary and with possible conjugate points. We assume that IΓ is known for geodesics belonging to an open set Γ with endpoint on the boundary. We prove generic s-injectivity and a stabilit…
Abstract manifolds split with no conjugate points using special functions.
problem Splitting compact manifolds without conjugate points.
method Developed functions that vanish under certain conditions on central Busemann functions.
result Central Busemann functions split linearly under specific conditions.
Study analyzes Lévy process structure on manifolds with conjugate points.
problem Microlocal analysis of Lévy processes on manifolds with conjugate points.
method Microlocal analysis, pseudodifferential operators, Fourier integral operators.
result Generator can be expressed as sum of pseudodifferential and Fourier integral operators.
Classifies 3D manifold diffeos without heteroclinic curves.
problem Classifying Morse-Smale diffeomorphisms on 3-manifolds.
method Defines equivalence class by embedding heteroclinic laminations.
result Equivalence class determined by laminations' embedding.
The paper proves rigidity for Anosov geodesic flows on certain manifolds.
problem Rigidity of Anosov geodesic flows on specific manifolds.
method Analyzing sectional curvatures and applying rigidity results.
result Rigidity holds for Anosov geodesic flows on manifolds with bounded negative sectional curvatures.
Paper proves existence of conjugate points on ellipsoids but not on spheres.
problem Existence of conjugate points in incompressible Euler flows.
method Formulated a differential-geometric criterion (M-criterion) and analyzed flows on spheres and ellipsoids.
result Zonal flows on ellipsoids can satisfy M-criterion, while not on spheres.
We consider an equivariant analogue of a conjecture of Borcherds. Let Y be a real K3 surface without real points. Let g be a Ricci-flat Kaehler metric on Y invariant under the complex conjugation. We shall prove that the equivariant determinant of the Laplacian of (Y,g) with respect to the complex conjugation…
Study on conjugate points in a C∗-algebra's Grassmann manifold.
problem Characterizing conjugate points in a C∗-algebra's Grassmann manifold. method Analyzes connections and geodesics in the Riemannian metric induced by the Killing form.
result Points that are tangent conjugate in the classical setting may not be conjugate in a C∗-algebra's Grassmann manifold. Existence of a conjugate point proven on 3D ellipsoid.
problem Existence of conjugate points in incompressible Euler flow on 3D ellipsoid.
method Volume-preserving diffeomorphism group, Misiolek curvature criterion.
result Existence of a conjugate point on 3D ellipsoid.
We prove that the topology, smooth structure, and metric of a compact Lorentzian manifold with boundary is uniquely determined by data at the boundary. The data consists of the lengths and directions of future-directed once-broken geodesics connecting points on the boundary, which are first timelike and then lightlike.…
Study finds conjugate points in geodesics of Kolmogorov flows on torus.
problem Characterizing pairs of integers (m,n) for which geodesics have conjugate points.
method Analysis of geodesics in the group of volume-preserving diffeomorphisms of a torus using stream functions.
result Existence of conjugate points for all pairs of strictly positive integers (m,n).
From a spray space S on a manifold M we construct a new geometric space P of larger dimension with the following properties: 1. Geodesics in P are in one-to-one correspondence with parallel Jacobi fields of M. 2. P is complete if and only if S is complete. 3. If two geodesics in P meet at one point, the…
We show a Hopf type rigidity for thermostats without conjugate points on a 2-torus
Extends E. Hopf's theorem to magnetic systems without conjugate points.
problem Proving magnetic curvature non-positive for magnetic systems without conjugate points.
method Using magnetic curvature introduced by the first author, proving magnetic flatness conditions.
result Magnetic flatness is a rigid condition with specific metric and curvature properties.
What are appropriate geometric conditions ensuring that a complete Riemannian 2-cylinder without conjugate points is flat? Examples with nonpositive curvature show that one has to assume that the ends of the cylinder open sublinearly. We show that sublinear growth of the ends is indeed sufficient if it is measured by t…
Study geodesic ray transform on 2D manifolds with conjugate points.
problem Understanding geodesic ray transform on manifolds with conjugate points.
method Decomposition into pseudodifferential operator and Fourier integral operators using method of stationary phase.
result Explicit computation of principal symbol and cancellation of singularities.
Support theorem proved for X-ray transform on certain non-compact manifolds.
problem Support theorem for X-ray transform on non-compact manifolds with conjugate points.
method Use of plane covers and support theorem for simple manifolds by Krishnan.
result Support theorem proved for simply connected 2-step nilpotent Lie groups and some non-homogeneous 3D manifolds.
Study on sub-Riemannian manifolds, focusing on conjugate points and caustic stability.
problem Analyzing sub-Riemannian manifolds and their conjugate points.
method Computed sub-Riemannian Hamiltonian flow, approximated conjugate locus, introduced geometric invariant.
result Contact distributions exhibit unique behavior, different from 3D case.
A complete Riemannian manifold without conjugate points is called asymptotically harmonic if the mean curvature of its horospheres is a universal constant. Examples of asymptotically harmonic manifolds include flat spaces and rank one locally symmetric spaces of noncompact type. In this paper we show that this list exh…