281 citations · 1.9k across the 34 of their papers we have counts for
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Taming the Aretakis instability: extremal black holes with multi-degenerate horizons
Shreyansh Agrawal, Panagiotis Charalambous, Laura Donnay +2
Stationary black hole geometries with non-degenerate Cauchy horizons are classically unstable due to mass inflation. At extremality, mass inflation is absent, but a different dynam…
Generalized Couch--Torrence inversions
Panagiotis Charalambous, Laura Donnay, Alexandru Lupsasca
The Laplace equation on Euclidean flat space admits a discrete radial inversion symmetry. In 1983, Couch and Torrence (CT) found -- surprisingly -- that the massless wave equation…
Inferring fundamental spacetime symmetries with gravitational-wave memory: from LISA to the Einstein Telescope
Boris Goncharov, Laura Donnay, Jan Harms
We revisit gravitational wave (GW) memory as the key to measuring spacetime symmetries, extending beyond its traditional role in GW searches. In particular, we show how these symme…