activity
20242026
collaborators

5 papers

math.AP2026

Homogenization and operator estimates for Steklov problems in perforated domains

Andrii Khrabustovskyi, Jari Taskinen

Let the set be obtained from the bounded domain by removing a family of -periodically distributed identical balls. In one consid…

math.SP2026

Periodic discrete graphs with prescribed spectrum

Andrii Khrabustovskyi, Anna Muranova

We construct a periodic weighted graph whose discrete Laplacian has a spectrum with precisely gaps. Moreover, we show that by an appropriate choice of the weights, the endpoint…

math.AP2025

A geometric approximation of non-local interface and boundary conditions

Pavel Exner, Andrii Khrabustovskyi

We analyze an approximation of a Laplacian subject to non-local interface conditions of a -type by Neumann Laplacians on a family of Riemannian manifolds with a sieve-like str…

gr-qc2025

Quasinormal Ringing and Shadows of Black Holes and Wormholes in Dark Matter-Inspired Weyl Gravity

Roman A. Konoplya, Andrii Khrabustovskyi, Jan Kříž +1

Weyl gravity naturally generates effective dark matter and cosmological constant terms as integration constants, eliminating the need to explicitly introduce them into the theory.…

math.SP2024

Quantum lattice transport along an infinitely extended perturbation

Marzieh Baradaran, Pavel Exner, Andrii Khrabustovskyi

We consider a periodic quantum graph in the form of a rectangular lattice with the -coupling of strength in the vertices perturbed by changing the latter at an infinite st…