72 citations · 101 across the 13 of their papers we have counts for
16 papers
Harmonic mappings, univalence criteria and a theorem of Lehtinen
Iason Efraimidis, Rodrigo Hernández
The harmonic inner radius of a planar domain is the largest constant with which a univalence criterion via the Schwarzian derivative holds for harmonic mappings. We sh…
On Hardy spaces, univalent functions and the second coefficient
Martin Chuaqui, Iason Efraimidis, Rodrigo Hernández
We consider normalized univalent functions with prescribed second Taylor coefficient . For convex functions we study the Hardy spaces to which and belong, refinin…
Hyperbolic convexity of holomorphic level sets
Iason Efraimidis, Pavel Gumenyuk
We prove that the sublevel set , , is geodesically convex with resp…
Korenblum's principle for Bergman spaces with radial weights
Iason Efraimidis, Adrián Llinares, Dragan Vukotić
We show that the Korenblum maximum (domination) principle is valid for weighted Bergman spaces with arbitrary (non-negative and integrable) radial weights in the case $…
Estimates for truncated area functionals on the Bloch space
Iason Efraimidis, Alejandro Mas, Dragan Vukotić
Recently, Kayumov \cite{K} obtained a sharp estimate for the -th truncated area functional for normalized functions in the Bloch space for and then, together with Wirth…
Ahlfors-Weill extensions for harmonic mappings
Iason Efraimidis, Rodrigo Hernández, María J. Martín
We provide two new formulas for quasiconformal extension to for harmonic mappings defined in the unit disk and having sufficiently small Schwarzian derivati…
Quasiconformal extension for harmonic mappings on finitely connected domains
Iason Efraimidis
We prove that a harmonic quasiconformal mapping defined on a finitely connected domain in the plane, all of whose boundary components are either points or quasicircles, admits a qu…
Criteria for univalence and quasiconformal extension for harmonic mappings on planar domains
Iason Efraimidis
If is a simply connected domain in then, according to the Ahlfors-Gehring theorem, is a quasidisk if and only if there exists a sufficient condition…
Schwarzian derivatives for pluriharmonic mappings
Iason Efraimidis, Álvaro Ferrada-Salas, Rodrigo Hernández +1
A pre-Schwarzian and a Schwarzian derivative for locally univalent pluriharmonic mappings in are introduced. Basic properties such as the chain rule, multiplicative…
A class of Weierstrass-Enneper lifts of harmonic mappings
Martin Chuaqui, Iason Efraimidis
We introduce a class of Weierstrass-Enneper lifts of harmonic mappings which satisfy a criterion for univalence introduced by Duren, Osgood and the first author in [J. Geom. Anal.…
Some more counterexamples for Bombieri's conjecture on univalent functions
Iason Efraimidis, Carlos Pastor
We disprove a conjecture of Bombieri regarding univalent functions in the unit disk in some previously unknown cases. The key step in the argument is showing that the global minimu…
On the failure of Bombieri's conjecture for univalent functions
Iason Efraimidis
A conjecture of Bombieri states that the coefficients of a normalized univalent function should satisfy $$ \liminf_{f\to K} \frac{n-{\rm Re\,}a_n}{m-{\rm Re\,}a_m} = \min_{t\in…
Applications of Livingston-type inequalities to the generalized Zalcman functional
Iason Efraimidis, Dragan Vukotić
We obtain sharp estimates for a generalized Zalcman coefficient functional with a complex parameter for the Hurwitz class and the Noshiro-Warschawski class of univalent functions a…
On harmonic Bloch-type mappings
I. Efraimidis, J. Gaona, R. Hernández +1
Let be a complex-valued harmonic mapping defined in the unit disk . We introduce the following notion: we say that is a Bloch-type function if its Jacobian satis…
A generalization of Livingston's coefficient inequalities for functions with positive real part
Iason Efraimidis
For functions holomorphic in the unit disk, satisfying , we generalize two inequalities proved by Livingston in 1969 an…
On the generalized Zalcman functional for some classes of univalent functions
Iason Efraimidis, Dragan Vukotić
We prove three sharp estimates for the generalized Zalcman coefficient functional: one for the Hurwitz class, another for the Noshiro-Warschawski class, and yet another for the fun…