English
Related papers

Related papers: On discs in bidiscs

200 papers

It is well known that every Hoelder-continuous function on the unit circle is the sum of two functions such that one of these two functions extends holomorphically into the unit disc and the other extends holomorphically into the complement…

Complex Variables · Mathematics 2007-05-23 Josip Globevnik

For an orientable surface with an area form, there are two invariants of area-preserving dynamics, the flux homomorphism and the Calabi invariant. Tsuboi found a remarkable connection between the Calabi invariant on the closed disk and a…

Geometric Topology · Mathematics 2025-08-19 KyeongRo Kim , Shuhei Maruyama

Under very general conditions it is shown that if $A$ is a uniform algebra generated by real-analytic functions, then either $A$ consists of all continuous functions or else there exists a disc on which every function in $A$ is holomorphic.…

Complex Variables · Mathematics 2017-10-10 Alexander J. Izzo

In one complex variable it is well known that if we consider the family of all holomorphic functions on the unit disc that fix the origin and with first derivative equal to 1 at the origin, then there exists a constant $\rho$, independent…

Complex Variables · Mathematics 2016-08-02 Cinzia Bisi

We give an example of a parabolic holomorphic self-map $f$ of the unit ball $\mathbb B^2\subset \mathbb C^2$ whose canonical Kobayashi hyperbolic semi-model is given by an elliptic automorphism of the disc $\mathbb D\subset \mathbb C$,…

Complex Variables · Mathematics 2024-03-05 Leandro Arosio , Filippo Bracci , Herv/'e Gaussier

It is shown that for a map $f \colon X \to Y$ of compact spaces the unital $\ast$-homomorphism $C(f) \colon C(Y) \to C(X)$ is projective in the category $\operatorname{Mor}({\mathcal C}^{1})$ precisely when $X$ is a dendrite and $f$ is…

Operator Algebras · Mathematics 2011-02-03 Alex Chigogidze

We study biharmonic maps between conformally compact manifolds, a large class of complete manifolds with bounded geometry, asymptotically negative curvature, and smooth compactification. These metrics provide a far-reaching generalization…

Differential Geometry · Mathematics 2026-01-14 Marco Usula

We identify all uniform limits of polynomials on the closed unit disc with respect to the chordal metric \c{hi} . One such limit is f=oo. The other limits are holomorphic functions f:-->C so that for every {\zeta} in the boundary of unit…

Complex Variables · Mathematics 2014-02-26 Vassilis Nestoridis

We show that the open unit ball $\mathbb{B}^n$ of $\mathbb{C}^n$ $(n>1)$ admits a nonsingular holomorphic foliation by complete properly embedded holomorphic discs.

Complex Variables · Mathematics 2020-10-27 Antonio Alarcon , Franc Forstneric

We show that if $E$ is a closed convex set in $\mathbb C^n$ $(n>1)$ contained in a closed halfspace $H$ such that $E\cap bH$ is nonempty and bounded, then the concave domain $\Omega = \mathbb C^n\setminus E$ contains images of proper…

Complex Variables · Mathematics 2023-08-07 Barbara Drinovec Drnovsek , Franc Forstneric

We show that there is no bi-Lipschitz homeomorphism of $\mathbb{R}^2$ that maps a spiral with a sub-exponential decay of winding radii to an unwinded arc. This result is sharp as shows an example of a logarithmic spiral.

Geometric Topology · Mathematics 2016-03-11 Alexander Fish , Laurentiu Paunescu

In this paper we construct for every integer $n>1$ a complex manifold of dimension $n$ which is exhausted by an increasing sequence of biholomorphic images of $\mathbb C^n$ (i.e., a long $\mathbb C^n$), but it does not admit any nonconstant…

Complex Variables · Mathematics 2017-01-25 Luka Boc Thaler , Franc Forstneric

The paper gives the following characterization of the disc algebra in terms of the argument principle: A continuous function f on the unit circle T extends holomorphically through the unit disc if and only if for each polynomial P such that…

Complex Variables · Mathematics 2007-05-23 Josip Globevnik

The aim of this paper is to prove that there exists no cohomogeneity one $G-$invariant proper biharmonic hypersurface into the Euclidean space ${\mathbb R}^n$, where $G$ denotes a tranformation group which acts on ${\mathbb R}^n$ by…

Differential Geometry · Mathematics 2016-06-22 Stefano Montaldo , Cezar Oniciuc , Andrea Ratto

Let B be the open unit ball in C^2 and let a, b be two points in B. It is known that for every positive integer k there is a function f in C^k(bB) which extends holomorphically into B along any complex line passing through either a or b yet…

Complex Variables · Mathematics 2009-12-03 Josip Globevnik

A manifold is T-embedded into an affine space if its tangent spaces at distinct points are disjoint. We prove that an n-dimensional disc cannot be T-embedded into 2n-dimensional space.

Differential Geometry · Mathematics 2007-05-23 G. Stojanovic , S. Tabachnikov

We construct an example showing that the solution map of the Euler equations is not continuous in the H\"older space from $C^{1,\alpha}$ to $L^\infty_tC^{1,\alpha}_x$ for any $0<\alpha<1$. On the other hand we show that it is continuous…

Analysis of PDEs · Mathematics 2017-04-28 Gerard Misiołek , Tsuyoshi Yoneda

We first give an exposition on holomorphic isometries from the Poincar\'e disk to polydisks and from the Poincar\'e disk to the product of the Poincar\'e disk with a complex unit ball. As an application, we provide an example of proper…

Complex Variables · Mathematics 2017-06-26 Shan Tai Chan , Ming Xiao , Yuan Yuan

We study holomorphic maps between C$^*$-algebras $A$ and $B$. When $f:B_A (0,\varrho) \longrightarrow B$ is a holomorphic mapping whose Taylor series at zero is uniformly converging in some open unit ball $U=B_{A}(0,\delta)$ and we assume…

Operator Algebras · Mathematics 2013-10-02 Jorge J. Garcés , Antonio M. Peralta , Daniele Puglisi , María I. Ramírez

In this paper, we show that the nonexistence of rotationally symmetric harmonic diffeomorphism between the unit disk without the origin and a punctured disc with hyperbolic metric on the target.

Differential Geometry · Mathematics 2013-05-17 Li Chen , Shi-Zhong Du , Xu-Qian Fan