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Related papers: Conformally Natural extensions revisited

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We introduce the notions of \textit{conformal barycenter} and \textit{holomorphic barycenter} of a measurable set $D$ in the hyperbolic ball. The two barycenters coincide in the disk, but they differ in multidimensional balls $\mathbb{C}^m…

Differential Geometry · Mathematics 2024-11-26 Vladimir Jacimovic , David Kalaj

The barycentric extension due to Douady and Earle gives a conformally natural extension of a quasisymmetric automorphism of the circle to a quasiconformal automorphism of the unit disk. We consider such extensions for circle diffeomorphisms…

Complex Variables · Mathematics 2017-09-01 Katsuhiko Matsuzaki

There is a classical extension, of M\"obius automorphisms of the Riemann sphere into isometries of the hyperbolic space $\mathbb{H}^3$, which is called the Poincar\'e extension. In this paper, we construct extensions of rational maps on the…

Dynamical Systems · Mathematics 2013-05-31 Carlos Cabrera , Peter Makienko , Guillermo Sienra

For a function defined on an arbitrary subset of a Riemann surface, we give conditions which allow the function to be extended conformally. One folkloric consequence is that two common definitions of an analytic arc in ${\mathbb C}$ are…

Complex Variables · Mathematics 2014-06-16 P. M. Gauthier , V. Nestoridis

We establish a connection between two previously unrelated topics: a particular discrete version of conformal geometry for triangulated surfaces, and the geometry of ideal polyhedra in hyperbolic three-space. Two triangulated surfaces are…

Geometric Topology · Mathematics 2015-09-02 Alexander Bobenko , Ulrich Pinkall , Boris Springborn

Biharmonic and conformal-biharmonic maps are two fourth-order generalizations of the well-studied notion of harmonic maps in Riemannian geometry. In this article we consider maps into the Euclidean sphere and investigate a geometric…

Differential Geometry · Mathematics 2026-03-09 Volker Branding

The main objective of this paper is to show that balls under invariant metrics on hyperbolic planar domains are finitely-connected. As applications, we give new and transparent proofs of classical results on conformal mappings of planar…

Complex Variables · Mathematics 2025-02-04 Bharathi Thiruvengadam , Jaikrishnan Janardhanan

We present a few ways of using conformal maps in the reconstruction of two-dimensional conductivities in electrical impedance tomography. First, by utilizing the Riemann mapping theorem, we can transform any simply connected domain of…

Numerical Analysis · Mathematics 2017-02-27 Nuutti Hyvönen , Lassi Päivärinta , Janne P. Tamminen

We study extensions of the measure of maximal entropy to suitable compactifications of the parameter space and the moduli space of rational maps acting on the Riemann sphere. For parameter space, we consider a space which resolves the…

Dynamical Systems · Mathematics 2026-04-29 Jan Kiwi , Hongming Nie

A conformal metric $g$ with constant curvature one and finite conical singularities on a compact Riemann surface $\Sigma$ can be thought of as the pullback of the standard metric on the 2-sphere by a multi-valued locally univalent…

Differential Geometry · Mathematics 2016-01-20 Qing Chen , Wei Wang , Yingyi Wu , Bin Xu

Classical extremal length (or conformal modulus) is a conformal invariant involving families of paths on the Riemann sphere. In ``Extremal length and functional completion'', Fuglede initiated an abstract theory of extremal length which has…

Complex Variables · Mathematics 2024-08-23 Kai Rajala

In this paper (Math. Res. Lett. 13 (2006). No 4, 509-523), the authors established a pseudo-normal form for proper holomoprhic mappings between balls in complex spaces with degenerate rank. This then was used to give a complete…

Complex Variables · Mathematics 2007-05-23 Xiaojun Huang , Shanyu Ji , Dekang Xu

Roughly speaking, let us say that a map between metric spaces is large scale conformal if it maps packings by large balls to large quasi-balls with limited overlaps. This quasi-isometry invariant notion makes sense for finitely generated…

Differential Geometry · Mathematics 2017-11-28 Pierre Pansu

We examine the correspondence between the conformal field theory of boundary operators and two-dimensional hyperbolic geometry. By consideration of domain boundaries in two-dimensional critical systems, and the invariance of the hyperbolic…

High Energy Physics - Theory · Physics 2009-10-22 P. Kleban , I. Vassileva

The historical developments of conformal transformations and symmetries are sketched: Their origin from stereographic projections of the globe, their blossoming in two dimensions within the field of analytic complex functions, the generic…

History and Philosophy of Physics · Physics 2009-12-07 H. A. Kastrup

Given a Moebius homeomorphism $f : \partial X \to \partial Y$ between boundaries of proper, geodesically complete CAT(-1) spaces $X,Y$, we describe an extension $\hat{f} : X \to Y$ of $f$, called the circumcenter map of $f$, which is…

Differential Geometry · Mathematics 2017-10-12 Kingshook Biswas

We consider a conformally invariant version of the Calder\'on problem, where the objective is to determine the conformal class of a Riemannian manifold with boundary from the Dirichlet-to-Neumann map for the conformal Laplacian. The main…

Analysis of PDEs · Mathematics 2016-12-26 Matti Lassas , Tony Liimatainen , Mikko Salo

We first prove a version of Tietze-Urysohn's theorem for proper functions taking values in non-negative real numbers defined on $\sigma$-compact locally compact Hausdorff spaces. As its application, we prove an extension theorem of proper…

Metric Geometry · Mathematics 2022-12-27 Yoshito Ishiki

We consider the case with boundary of the classical Kazdan-Warner problem in dimension greater or equal than three, i.e. the prescription of scalar and boundary mean curvatures via conformal deformations of the metric. We deal in particular…

Analysis of PDEs · Mathematics 2021-05-12 S. Cruz-Blázquez , A. Malchiodi , D. Ruiz

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 "${\frac12}$-dimensional measure" with respect to the pseudo-Riemannian structure of the set of circles is…

Differential Geometry · Mathematics 2016-03-21 Rémi Langevin , Jun O'Hara
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