Konstantinos Zemas

activity

20192026

most citedRigidity estimates for isometric and conformal maps from

S^{n - 1}

R^{n}

6 citations · 14 across the 14 of their papers we have counts for

collaborators

15 papers

math.AP2026

Some lifting and approximation properties for maps in $W^{1, 2} (B^{3}; S^{2})$

André Guerra, Xavier Lamy, Konstantinos Zemas

Smooth maps $u : B^{3} \to S^{2}$ can be lifted to $u^: B^{3} \to S^{3}$ using the Hopf fibration $h : S^{3} \to S^{2}$ via the factori…

math.OC2026

Atomic Gradient Flows: Gradient Flows on Sparse Representations

Christian Amend, Marcello Carioni, Konstantinos Zemas

One of the most popular approaches for solving total variation-regularized optimization problems in the space of measures are Particle Gradient Flows (PGFs). These restrict the pro…

math.AP2025

Global minimality of the Hopf map in the Faddeev-Skyrme model with large coupling constant

André Guerra, Xavier Lamy, Konstantinos Zemas

We prove that, modulo rigid motions, the Hopf map is the unique minimizer of the Faddeev--Skyrme energy in its homotopy class, provided that the radius of the target 2-sphere is no…

math.AP2025

Derivation of Kirchhoff-type plate theories for elastic materials with voids

Manuel Friedrich, Leonard Kreutz, Konstantinos Zemas

We rigorously derive a Blake-Zisserman-Kirchhoff theory for thin plates with material voids, starting from a three-dimensional model with elastic bulk and interfacial energy featur…

math.AP2024

On the existence of degenerate solutions of the two-dimensional $H$ -system

André Guerra, Xavier Lamy, Konstantinos Zemas

We consider entire solutions $ω \in H ˙^{1} (R^{2}; R^{3})$ of the $H$ -system $Δ ω = 2 ω_{x} \land ω_{y},$ which we refer to as bubbles. Surprisingly, and contrary to conjectures r…

math.AP2024★ 1 cited

Energy barriers for boundary nucleation in a two-well model without gauge invariance

Antonio Tribuzio, Konstantinos Zemas

We study energy scaling laws for a simplified, singularly perturbed, double-well nucleation problem confined in a half-space, in the absence of gauge invariance and for an inclusio…

math.DG2024

Optimal quantitative stability of the Möbius group of the sphere in all dimensions

André Guerra, Xavier Lamy, Konstantinos Zemas

In any dimension $n \geq 3$ , we prove an optimal stability estimate for the Möbius group among maps $u : S^{n - 1} \to R^{n}$ , of the form $\inf_{λ>0,ϕ\in \mathrm{Mö…

math.AP2023

Homogenisation of nonlinear Dirichlet problems in randomly perforated domains under minimal assumptions on the size of perforations

Lucia Scardia, Konstantinos Zemas, Caterina Ida Zeppieri

In this paper we study the convergence of integral functionals with $q$ -growth in a randomly perforated domain of $R^{n}$ , with $1 < q < n$ . Under the assumption that the perfora…

math.AP2023★ 1 cited

Sharp quantitative stability of the Möbius group among sphere-valued maps in arbitrary dimension

André Guerra, Xavier Lamy, Konstantinos Zemas

In this work we prove a sharp quantitative form of Liouville's theorem, which asserts that, for all $n \geq 3$ , the weakly conformal maps of $S^{n - 1}$ with degree $\pm 1$ ar…

math.AP2023

Derivation of effective theories for thin 3D nonlinearly elastic rods with voids

Manuel Friedrich, Leonard Kreutz, Konstantinos Zemas

We derive a dimension-reduction limit for a three-dimensional rod with material voids by means of $Γ$ -convergence. Hereby, we generalize the results of the purely elastic setting […

math.AP2022★ 5 cited

From atomistic systems to linearized continuum models for elastic materials with voids

Manuel Friedrich, Leonard Kreutz, Konstantinos Zemas

We study an atomistic model that describes the microscopic formation of material voids inside elastically stressed solids under an additional curvature regularization at the discre…

math.AP2021★ 1 cited

Geometric rigidity in variable domains and derivation of linearized models for elastic materials with free surfaces

Manuel Friedrich, Leonard Kreutz, Konstantinos Zemas

We present a quantitative geometric rigidity estimate in dimensions $d = 2, 3$ generalizing the celebrated result by Friesecke, James, and Müller to the setting of variable domains. L…

math.AP2021

A note on a rigidity estimate for degree $\pm 1$ conformal maps on $S^{2}$

Jonas Hirsch, Konstantinos Zemas

In this note we present a short alternative proof of an estimate obtained by A.B.-Mantel, C.B. Muratov and T.M. Simon in [3] regarding the rigidity of degree { $\pm 1$ } conformal ma…

math.AP2021★ 6 cited

Rigidity estimates for isometric and conformal maps from $S^{n - 1}$ to $R^{n}$

Stephan Luckhaus, Konstantinos Zemas

We investigate both linear and nonlinear stability aspects of rigid motions (resp. Möbius transformations) of $S^{n - 1}$ among Sobolev maps from $S^{n - 1}$ into $\m…

math.DG2019

Stability estimates for the conformal group of $S^{n - 1}$ in dimension $n \geq 3$

Stephan Luckhaus, Konstantinos Zemas

The purpose of this paper is to exhibit a quantitative stability result for the class of Möbius transformations of $S^{n - 1}$ when $n \geq 3$ . The main estimate is of local…

Some lifting and approximation properties for maps in W1,2(B3;S2)

Atomic Gradient Flows: Gradient Flows on Sparse Representations

Global minimality of the Hopf map in the Faddeev-Skyrme model with large coupling constant

Derivation of Kirchhoff-type plate theories for elastic materials with voids

On the existence of degenerate solutions of the two-dimensional H-system

Energy barriers for boundary nucleation in a two-well model without gauge invariance

Optimal quantitative stability of the Möbius group of the sphere in all dimensions

Homogenisation of nonlinear Dirichlet problems in randomly perforated domains under minimal assumptions on the size of perforations

Sharp quantitative stability of the Möbius group among sphere-valued maps in arbitrary dimension

Derivation of effective theories for thin 3D nonlinearly elastic rods with voids

From atomistic systems to linearized continuum models for elastic materials with voids

Geometric rigidity in variable domains and derivation of linearized models for elastic materials with free surfaces

A note on a rigidity estimate for degree ±1 conformal maps on S2

Rigidity estimates for isometric and conformal maps from Sn−1 to Rn

Stability estimates for the conformal group of Sn−1 in dimension n≥3

Some lifting and approximation properties for maps in $W^{1, 2} (B^{3}; S^{2})$

On the existence of degenerate solutions of the two-dimensional $H$ -system

A note on a rigidity estimate for degree $\pm 1$ conformal maps on $S^{2}$

Rigidity estimates for isometric and conformal maps from $S^{n - 1}$ to $R^{n}$

Stability estimates for the conformal group of $S^{n - 1}$ in dimension $n \geq 3$