3 papers
gr-qc2026
Scalar charge bounds for extremal black hole formation
Berend Schneider
I prove that a collapsing charged scalar field with scalar charge that forms an exactly extremal Reissner--Nordström black hole à la Kehle--Unger with radius m…
astro-ph.HE2026
EP250302a: violent shell collision in a soft-X-ray-selected GRB-like transient
Shao-Yu Fu, Cui-Yuan Dai, Ai-Ling Wang +57
The Einstein Probe opens a previously unexplored soft X-ray window onto gamma-ray bursts, filling a critical observational gap in the soft X-ray coverage of their prompt emission.…
gr-qc2026
Self-gravitating thin shells are dynamically unstable on all angular scales
Tristan Pitre, Berend Schneider, Eric Poisson
We establish the dynamical instability of a static, spherically symmetric, and infinitesimally thin shell in general relativity. The shell is made up of a perfect fluid with a baro…