26th Australian Institute of Physics Congress and the Australian and New Zealand Conference on Optics and Photonics

Physical Black Holes: Properties and Observational Tests

Not scheduled

1h

Belinda Hutchinson Building (The University of Sydney )

Contributed Oral AIP | General Relativity and Gravitation (ASGRG) Afternoon Tea and Poster Session 1

Speaker

Daniel Terno

Description

A physical black hole is a light-trapping region whose apparent horizon forms in finite time for a distant observer, irrespective of whether an event horizon exists. Recent work shows that, if such objects form, their near-horizon geometry is not merely a dynamical version of the Schwarzschild or Kerr picture: it has unusual structural properties and features that differ substantially from eternal black holes.

The central problem is whether these differences are observationally relevant. We take first steps towards its solution by developing effective near-horizon and interpolating descriptions suitable for computing signatures such as light rings and quasinormal modes. In addition, cosmological embedding provides a sharp test: hypothetical physical black holes do not couple to the large-scale structure of the Universe. Together, these results begin to translate the finite-time formation requirement into observational signatures and broader tests of the standard black-hole paradigm.

D. R. Terno, Apparent horizon as a membrane, Phys. Rev. D 113, 124019 (2026).
S. Maharana, F. Simovic, I. Soranidis, and D. R. Terno, Padé metrics for black hole perturbations and light rings, Phys. Rev. D 111, 104063 (2025).
P. K. Dahal, S. Maharana, F. Simovic, I. Soranidis, and D. R. Terno, Black holes as spherically-symmetric horizon-bound objects, Phys. Rev. D 110, 044032 (2024)