activity
20242026
collaborators

8 papers

gr-qc2026

On the uniqueness of continuous spacetime extensions in 1+1 dimensions with applications to weak null singularities

Peter Cameron, Jan Sbierski

Motivated by weak null singularities in black hole interiors, we study 1+1 dimensional Lorentzian manifolds which admit a continuous spacetime extension across a null bound…

gr-qc2026

A note on the instability of the Kerr Cauchy horizon under linearised gravitational perturbations

Jan Sbierski

This note slightly strengthens the result of arXiv:2201.12295 on the linear instability of the Kerr Cauchy horizon. This strengthened result is used in the proof arXiv:2604.04877 o…

gr-qc2026

The formation of a weak null singularity in the interior of generic rotating black holes

Jonathan Luk, Jan Sbierski

Given a characteristic initial value problem with smooth data representing a dynamical event horizon settling down to that of Kerr in the subextremal, strictly rotating range with…

math.AP2026

A mathematical description of the spin Hall effect of light in inhomogeneous media

Sam C. Collingbourne, Marius A. Oancea, Jan Sbierski

We study Gaussian wave packet solutions for Maxwell's equations in an isotropic, inhomogeneous medium and derive a system of ordinary differential equations that captures the leadi…

math.AP2025

A quasilinear wave with a supersonic shock in a weak solution interrupting the classical development

Leonardo Abbrescia, Pieter Blue, Jan Sbierski +1

We study the Cauchy problem for classical and weak shock-forming solutions to a model quasilinear wave equation in dimensions arising from a convenient choice of

gr-qc2025

Lipschitz inextendibility of weak null singularities from curvature blow-up

Jan Sbierski

We prove the -inextendibility of weak null singularities without any symmetry assumptions. The proof introduces a new strategy to infer $C^{0,1}_{\mathrm{lo…