activity
20222026
collaborators

8 papers

math.AP2026

Plane wave representations for wave scattering on a sphere

Valentin D. Kunz, Andrey V. Shanin, Raphael C. Assier

Motivated by three-dimensional wave diffraction by conical shapes, we consider the two-dimensional problem of wave scattering on the real sphere resulting from a po…

physics.flu-dyn2026

Extension of a mathematical analogy between vortical flows without surface tension and irrotational capillary flows

Valentin D. Kunz, Saleh Tanveer, Darren G. Crowdy

In a recent paper, a mathematical analogy was found between two physically distinct classes of two-dimensional free boundary problems in inviscid fluid mechanics. One class involve…

math-ph2026

A mathematical analogy between certain hollow vortex and bubble flows - existence, uniqueness, and identical boundary shapes

Valentin D. Kunz, Saleh Tanveer, Darren G. Crowdy

We study two physically distinct steady free-boundary problems in a two-dimensional inviscid fluid: a hollow vortex in a constant-vorticity flow subject to simple shear, third orde…

math.CV2026

Degree-Three Rational Sphere Maps: Sharp Denominator Region and Gram Normal Forms

Eden Danielsen-Jensen, Dusty Grundmeier, Abdullah Al Helal +4

We study degree-three rational sphere maps in two complex variables. After a standard normalization, the denominator of such a map takes the form \[ g_σ(z)=1+σ_1 z_1^2+σ_2 z_2^2, \…

math.AP2026

Plane-wave representation for the Laplace--Beltrami equation on a sphere. Application to the Green's function

Andrey V. Shanin, Valentin D. Kunz, Raphael C. Assier

We propose an extension of the plane-wave representation for wave fields defined on the real sphere . This representation is well-known in the planar setting but has…

math.AP2023

Diffraction by a right-angled no-contrast penetrable wedge: recovery of far-field asymptotics

Valentin D. Kunz, Raphael C. Assier

We provide a description of the far-field encountered in the diffraction problem resulting from the interaction of a monochromatic plane-wave and a right-angled no-contrast penetra…

math.AP2022

Diffraction by a Right-Angled No-Contrast Penetrable Wedge: Analytical Continuation of Spectral Functions

Valentin D. Kunz, Raphael C. Assier

We study the problem of diffraction by a right-angled no-contrast penetrable wedge by means of a two-complex-variable Wiener-Hopf approach. Specifically, the analyticity properties…

math.CV2022

Constructing Group-Invariant CR Mappings

Jennifer Brooks, Sean Curry, Dusty Grundmeier +4

We construct CR mappings between spheres that are invariant under actions of finite unitary groups. In particular, we combine a tensoring procedure with D'Angelo's construction of…