arXiv research

Develops Patterson-Sullivan theory for coarse cocycles.

Paper develops a theory for Patterson-Sullivan measures in higher rank symmetric spaces.

The paper introduces Patterson-Sullivan systems and proves their rigidity, with applications to random walks and entropy rigidity.

Sullivan discusses his contributions to math and physics.

We define the Simons-Sullivan differential analytic index by translating the Freed-Lott differential analytic index via explicit ring isomorphisms between Freed-Lott differential K-theory and Simons-Sullivan differential K-theory. We prove the differential Grothendieck-Riemann-Roch theorem in Simons-Sullivan differenti…

The paper connects geodesic flows and limit sets on visibility manifolds.

Extends Hopf-Tsuji-Sullivan dichotomy to higher rank groups and applies to Anosov subgroups.

Paper proves finite BMS measure for SPR groups in higher rank Lie groups.

New findings show mapping class groups of certain high-dimensional manifolds are not residually finite.

Unique entropy measure found for convex projective manifolds.

We give a finite dimensional approach to the Chas-Sullivan product on the free loop space of a manifold, orientable or not.

Prove a global shadow lemma for Patterson-Sullivan measures associated with relatively Morse subgroups in higher-rank semisimple Lie groups.

We show that uniform lattices in some semi-simple groups (notably complex ones) admit Anosov surface subgroups. This result has a quantitative version: we introduce a notion, called $K$-Sullivan maps, which generalizes the notion of $K$-quasi-circles in hyperbolic geometry, and show in particular that Sullivan maps are…

New findings on geometric flows and equidistribution in Hilbert geometry.

Proves classification of 4D complete intersections up to diffeomorphism.

The fundamental group of a hyperbolic manifold acts on the limit set, giving rise to a cross-product C^* algebra. We construct nontrivial K-cycles for the cross-product algebra, thereby extending some results of Connes and Sullivan to higher dimensions. We also show how the Patterson-Sullivan measure on the limit set c…

Develops measures for non-Borel Anosov groups on Furstenberg boundary.

We extend several notions and results from the classical Patterson-Sullivan theory to the setting of Anosov subgroups of higher rank semisimple Lie groups, working primarily with invariant Finsler metrics on associated symmetric spaces. In particular, we prove the equality between the Hausdorff dimensions of flag limit…

In this article, we consider the geodesic flow on a compact rank $1$ Riemannian manifold $M$ without focal points, whose universal cover is denoted by $X$. On the ideal boundary $X(\infty)$ of $X$, we show the existence and uniqueness of the Busemann density, which is realized via the Patterson-Sullivan measure. Based …

We prove that for a relatively hyperbolic group G there is a sequence of relatively hyperbolic proper quotients such that their growth rates converge to the growth rate of G. Under natural assumptions, the same conclusion holds for the critical exponent of a cusp-uniform action of G on a hyperbolic metric space. As a c…

Combines Kleinian groups and polynomials into a dynamical system.

The paper develops a theory of conformal density at infinity for groups with contracting elements.

For a fixed closed manifold $P$, we construct a cobordism category of embedded manifolds with a single Baas-Sullivan singularity of type $P$. Our main theorem identifies the homotopy type of the classifying space of this cobordism category with that of the infinite loop-space of a certain spectrum related to the spectr…

Study vanishing theorems for CR manifolds using contact forms and Laplacian formulas.

Discretizes diffusions and harmonic functions on covering spaces.

Develops a chain-level model for Chas-Sullivan products using Morse theory with differential graded coefficients.

Maximal representations show strong entropy rigidity.

Anosov groups limit sets are Ahlfors regular, with applications in Teichmüller spaces.

The paper extends geometric results from negatively-curved spaces to strictly convex Hilbert geometry.

Extends Morse-Novikov Homology to include differential graded coefficients and fibration structures.

We define generalized currents associated with immersions of abstract solenoids with a transversal measure. We realize geometrically the full real homology of a compact manifold with these generalized currents, and more precisely with immersions of minimal uniquely ergodic solenoids. This makes precise and geometric De…

The paper proves convergence of discrete maps to Riemann mappings for polyhedral surfaces.

New measure of maximal entropy found for a class of geometrically finite groups.

Proves finite measure implies product structure for certain discrete subgroups.

For a given list of closed manifolds $Σ_k=(P_1,...,P_k)$, we construct a cobordism category $\mathbf{Cob}_{d}^{Σ_{k}}$ of embedded manifolds with Baas-Sullivan singularities of type $Σ_k$. Our main results identify the homotopy type of the classifying spaces $B\mathbf{Cob}_{d}^{Σ_{k}}$ of these cobordism categories wit…

Method extends eigenfunction construction to non-symmetric spaces.

Using intersection theory in the context of Hilbert manifolds and geometric homology we show how to recover the main operations of string topology built by M. Chas and D. Sullivan. We also study and build an action of the homology of reduced Sullivan's chord diagrams on the singular homology of free loop spaces, extend…

Study shows exact dimensionality and regularity of manifolds for specific groups.

In his 1985 paper Sullivan sketched a proof of his structural stability theorem for differentiable group actions satisfying certain expansion-hyperbolicity axioms. In this paper we relax Sullivan's axioms and introduce a notion of "meandering hyperbolicity" for group actions on geodesic metric spaces. This generalizati…

A note on the uniqueness of differential characters and K-theory via homological algebra.

Research confirms a conjecture about complex manifolds with total Betti number three.

Quantifies how geodesic planes isolate in hyperbolic 3-manifolds.

The study examines the realizability of a 4-manifold invariant for homeomorphisms.

The paper studies ergodicity of flows on subspaces, generalizing earlier work.

Motivated by Bonahon's result for hyperbolic surfaces, we construct an analogue of the Patterson-Sullivan-Bowen-Margulis map from the Culler-Vogtmann outer space $CV(F_k)$ into the space of projectivized geodesic currents on a free group. We prove that this map is a topological embedding. We also prove that for every $…

We prove that distortion of a knotted curve in $\R^3$ is great than 4.76. This improves a result obtained by John M. Sullivan and Elizabeth Denne in \cite{DS}.

We give a sufficient condition for a metric (homology) manifold to be locally bi-Lipschitz equivalent to an open subset in $\rn$. The condition is a Sobolev condition for a measurable coframe of flat 1-forms. In combination with an earlier work of D. Sullivan, our methods also yield an analytic characterization for smo…

Researchers calculate alpha invariant for certain complex projective spaces.