The paper extends Santaló's ellipse measures to hitting probabilities for circle lattices.
problem Calculating hitting probabilities for ellipses intersecting circles.
method Deriving measures for all positions of a moving ellipse inside a fixed circle and calculating hitting probabilities for circle lattices.
result Hitting probabilities for lattices of circles are deduced from ellipse measures.
Study rigidity of PSU(1,1) actions on circle via harmonic measures.
problem Rigidity properties of surface group actions on the circle.
method Foliated harmonic measures and curvature estimates.
result Curvature estimate and Gauss--Bonnet formula for S1 connection. The Cannon-Thurston map's pushed measures on the circle are singular with respect to sphere measures.
problem Understanding the behavior of geodesics and measures on fibered hyperbolic 3-manifolds.
method Properties of geodesics and measures on the circle and sphere are analyzed to prove singularity.
result Natural measures on the circle become singular with respect to measures on the sphere.
New measure proves Poncelet-type theorems.
problem Proving Poncelet-type theorems.
method Introducing a new invariant measure on the circle.
result Simple proof of Emch closing theorem.
Stationary measures on hyperbolic surfaces with cusps are singular and stable under quasi-symmetries.
problem Understanding stationary measures on hyperbolic surfaces with cusps.
method Analyzing exponential decay of cusp excursions and proving quasi-symmetry stability.
result Stationary measures on hyperbolic surfaces with cusps are quasi-symmetrically stable and singular.
Let P be a locally finite circle packing in the plane invariant under a non-elementary Kleinian group Gamma and with finitely many Gamma-orbits. When Gamma is geometrically finite, we construct an explicit Borel measure on the plane which describes the asymptotic distribution of small circles in P, assuming that either…
The paper studies the geometry of probability measures on the unit circle.
problem Understanding the Riemannian geometry of probability measures on the unit circle.
method Developed an intrinsic framework using the Peter-Weyl Theorem to study the differential geometry of Wasserstein spaces of compact Lie groups.
result Explicitly demonstrated that the Wasserstein space of the unit circle is flat with vanishing curvature.
Study shows only circles have optimal curvature bounds.
problem Optimal curvature bounds for metric measure spaces.
method Analyzes spectrum of weighted Laplacian.
result One-dimensional circles are unique with optimal bounds.
The set of osculating circles of a given curve in $\SS^3$ forms a curve in the set of oriented circles in $\SS^3$. We show that its "21-dimensional measure" with respect to the pseudo-Riemannian structure of the set of circles is proportional to the conformal arc-length of the original curve, which is a confor…
Paper proves existence and uniqueness of circle patterns on surfaces with assigned geodesic curvatures.
problem Existence and uniqueness of circle patterns on surfaces with prescribed geodesic curvatures.
method Applied Perron's method and Thurston's algorithm to prove existence and convergence.
result Existence and uniqueness of circle patterns on surfaces with prescribed geodesic curvatures.
Theorems for harmonic functions on manifolds with unique conic measure.
problem Existence and properties of harmonic functions on manifolds.
method Integral sense Three Circles Theorems, nonnegative Ricci curvature, unique metric cone, conic measure, polynomial growth, frequency estimation.
result Existence of nonconstant harmonic functions with polynomial growth on manifolds with unique conic measure.
Using optimal transport we study some dynamical properties of expanding circle maps acting on measures by push-forward. Using the definition of the tangent space to the space of measures introduced by Gigli, their derivative at the unique absolutely continuous invariant measure is computed. In particular it is shown th…
Study the hanging chain shape around a circle.
problem Finding the shape of a curve extremizing potential energy to a circle.
method Analyzes curves minimizing potential energy to a circle, considering both inside and outside.
result Describes shapes of curves for different powers of distance to the circle.
This paper derives formulas for Chern classes of triangulated circle bundles using combinatorial necklaces.
problem Calculating Chern classes for triangulated circle bundles over polyhedra.
method Using triangulations and necklace combinatorics, the paper derives rational parity formulas for Chern classes.
result Rational parity formulas for Chern classes of triangulated circle bundles are derived.
Thurston's circle packing approximation of the Riemann Mapping (proven to give the Riemann Mapping in the limit by Rodin-Sullivan) is largely based on the theorem that any topological disk with a circle packing metric can be deformed into a circle packing metric in the disk with boundary circles internally tangent to t…
Study of Matsumoto maps on foliated bundles over hyperbolic manifolds.
problem Characterizing ergodic harmonic measures on foliated bundles.
method Analysis of actions of hyperbolic manifold groups on the circle.
result Suspension of actions with non-discrete images cannot admit Matsumoto maps of type I.
Maps and measures on surfaces link best Lipschitz and least gradient functions.
problem Analyzing maps between surfaces and their geometric properties.
method Duality between best Lipschitz and least gradient maps, geodesic laminations, and transverse measures.
result The infinity harmonic map defines a geodesic lamination and the least gradient map defines a transverse measure.
Sharp convergence rate for curvature stability in planar free elastic flow.
problem Stability of ω-circles under the planar free elastic flow. method Improved closeness measurement via curvature scalar, leading to a sharp convergence rate.
result Sharp convergence rate for curvature stability in planar free elastic flow.
The Cannon-Thurston map's measures become singular with respect to sphere measures.
problem Characterizing the behavior of measures under the Cannon-Thurston map.
method Analyzing the geometric properties of hyperbolic geodesics and quasi-geodesics.
result Natural measures on the circle become singular with respect to measures on the sphere.
Study Teichmüller dynamics and dilation tori properties, proving almost all vertical foliations are Morse-Smale.
problem Understanding the coarse geometry of dilation tori and Teichmüller flow dynamics.
method Analysis of moduli space of dilation tori, Teichmüller flow action, and piecewise affine circle homeomorphisms.
result Vertical foliations of dilation tori are almost always Morse-Smale.
We construct a compact symplectic manifold with a Hamiltonian circle action for which the Duistermaat-Heckman function is not log-concave.
Let $\cT$ be Teichmüller space of a closed surface of genus at least 2. For any point $c\in \cT$, we describe an action of the circle on $\cT\times \cT$, which limits to the earthquake flow when one of the parameters goes to a measured lamination in the Thurston boundary of $\cT$. This circle action shares some of the …
The Circle of Investment explains the investment process as a circle with many dots, highlighting uncertainties and providing new insights.
problem Uncertainties and ambiguities in the investment process.
method Analogies and the Black-Litterman framework to explain and quantify uncertainties.
result Introduces two new points to better understand investment uncertainties and confidence levels.
Slim curves on 3-sphere help spherical CR uniformizations.
problem Understanding curves on 3-sphere for CR uniformizations.
method Defining slimness, analyzing foliations, and applying to quasi-Fuchsian groups.
result Slim curves lead to spherical CR uniformizations of certain 3-manifolds.
This paper introduces persistent equivariant cohomology and applies it to circle actions.
problem Understanding the cohomology of filtered spaces with group actions.
method Persistent Borel equivariant cohomology, Serre spectral sequence, Gysin homomorphism.
result Explicit description and cohomology computation for circle actions.
Study shows similar result to Margulis for Cantor set homeomorphisms.
problem Understanding groups of homeomorphisms of Cantor sets.
method Analogous to Margulis's proof for linear groups.
result Groups of homeomorphisms either preserve a measure or contain a free subgroup.
We give a short proof of the fact that bounded earthquakes of the unit disk induce quasisymmetric maps of the unit circle. By a similar method, we show that symmetric maps are induced by bounded earthquakes with asymptotically trivial measures.
Extends Fatou theorem to bounded harmonic maps.
problem Classical Fatou theorem for bounded harmonic functions.
method Extending theorem to bounded harmonic maps.
result Identifies bounded harmonic maps on unit disk with bounded measurable functions on boundary.
In this note, I will discuss a possible relation between the Mahler measure of the colored Jones polynomial and the volume conjecture. In particular, I will study the colored Jones polynomial of the figure-eight knot on the unit circle. I will also propose a method to prove the volume conjecture for satellites of the f…
Milnor-Thurston homology theory is a construction of homology theory that is based on measures. It is known that it is equivalent to singular homology theory in case of manifolds and complexes. Its behaviour for non-tame spaces is still unknown. This paper provides results in this direction. We prove that Milnor-Thurst…
Study of flows on circle bundles over translation surfaces, showing decay of correlations.
problem Ergodic properties of flows on circle bundles over translation surfaces.
method Generalizing Heisenberg nilflows to more general base surfaces, showing relatively mixing.
result Showed that such flows exhibit decay of correlations in the orthogonal complement of functions constant along fibers.
A new state-sum formula for the evaluation of the Yang-Mills measure in the Kauffman bracket skein algebra of a closed surface is derived. The formula extends the Kauffman bracket to diagrams that lie in surfaces other than the plane. It also extends Turaev's shadow world invariant of links in a circle bundle over a su…
Study stability of measures on Kähler manifolds with Hamiltonian actions.
problem Stability of measures on Kähler manifolds under group actions.
method Identify and apply momentum mapping criteria for stability, semi-stability, and polystability.
result Various stability criteria for measures on Kähler manifolds.
Two optimization problems for Loewner energy curves and their symmetries.
problem Optimizing Jordan curves and positive curves on boundary spaces.
method Using conformal welding and Möbius transformations.
result Symmetries between boundary spaces and pleated planes.
Geometrization theorem, fibered case: Every three-manifold that fibers over the circle admits a geometric decomposition. Double limit theorem: for any sequence of quasi-Fuchsian groups whose controlling pair of conformal structures tends toward a pair of projectively measured laminations that bind the surface, there is…
The paper finds circle packings with specific curvatures in hyperbolic geometry.
problem Finding circle packings with prescribed total geodesic curvatures and discrete Gaussian curvatures.
method Established existence and rigidity via variational principle, introduced combinatorial p-th Calabi flows.
result Introduced combinatorial p-th Calabi flows to find circle packings with prescribed curvatures.
The paper examines random walks on metric spaces and finds commensurable subgroups.
problem Determining commensurable subgroups via stationary measures in metric spaces.
method Analyzing random walks on isometry groups of metric spaces with non-singular stationary measures.
result Subgroups generated by random walks are commensurable under mild conditions.
The fixed-point index of a homeomorphism of Jordan curves measures the number of fixed-points, with multiplicity, of the extension of the homeomorphism to the full Jordan domains in question. The now-classical Circle Index Lemma says that the fixed-point index of a positive-orientation-preserving homeomorphism of round…
Study generates infinite circle packings with a specific property.
problem Generating infinite circle packings with a unique property.
method Investigates an infinite family of circle packings and uses them to create Apollonian packings.
result Created an infinite set of circle packings with the Apollonian property.
Properness proven for circle packings and Delaunay patterns on complex projective structures.
problem Proving properness for circle packings and Delaunay patterns on complex projective structures.
method Considering circle packings and Delaunay circle patterns on surfaces with complex projective structures, proving properness of the forgetful map.
result Proved properness of the forgetful map sending circle packings and Delaunay patterns to underlying complex structures.
The paper extends Descartes' circle theorem to n-flower configurations using hyperbolic geometry.
problem Extending Descartes' circle theorem to n-flower configurations.
method Spinorial description of horospheres in hyperbolic geometry.
result An explicit equation satisfied by the curvatures of n-flower configurations.
The paper explores universal circles for Anosov foliations and their uniqueness.
problem Exploring the uniqueness of universal circles for Anosov foliations.
method Using the flow space of an Anosov flow to parameterize the circle bundle at infinity of the foliations.
result Several constructions of a universal circle are typically distinct and not conjugate.
Solves Apollonius' problem using oriented circles and inversive geometry.
problem Constructing a circle tangent to three given circles.
method Using oriented circles and inversive invariants, reversing each given circle to find solutions.
result The problem has 0, 1, or 2 solutions, depending on the configuration of given circles.
The study proves conditions for rigidity of Kleinian groups using measure theory and ergodic theory.
problem Conditions for rigidity of Kleinian groups via self-joinings.
method Ergodic theory for directional diagonal flows and conformal measure theory.
result Proves dichotomy conditions for Λ_f and Λ, with implications for the dimension and structure of limit sets.
Link projections with the same circle arrangement can be transformed by specific moves.
problem Characterizing link projections based on their circle arrangements.
method Local moves to transform link projections and analyze their circle arrangements.
result Two link projections have the same circle arrangement if and only if they can be transformed into each other by certain local moves.
Study of Alexander polynomials of torus knots and links, showing zeros equidistribute on unit circle.
problem Analyzing asymptotic behavior and distribution of zeros of Alexander polynomials of torus knots.
method Equidistribution analysis, moment sequence, Iwasawa theory, logarithmic Mahler measure.
result Zeros of Alexander polynomials of torus knots and links become equidistributed on the unit circle as p, q → ∞.
Proves rigidity of circle packings in the plane, generalizing previous work.
problem Rigidity of infinite inversive distance circle packings in the plane.
method Maximal principle for generic weighted Delaunay inversive distance circle packings and ring lemma for inversive distance circle packings in hexagonal triangulated plane.
result Proves Bowers-Stephenson's conjecture for inversive distance circle packings.
A 1-parameter family of Steiner chains has constant curvature moments.
problem Characterize the curvature moments of a 1-parameter family of Steiner chains.
method Proved constant curvature moments for k=3 using Descartes Circle Theorem; extended to spherical and hyperbolic geometries.
result First k-1 moments of curvatures remain constant in a 1-parameter family of Steiner chains.