Overview

• The IFPU-led paper identifies three black hole models: classical singular, regular non-singular, and horizonless mimickers.
• Quantum gravity effects are proposed to eliminate singularities, addressing the breakdown of general relativity in extreme conditions.
• Future observations, including photon-ring imaging and gravitational-wave analysis, are highlighted as tools to distinguish non-singular models from classical black holes.
• The collaborative review emerged from an interdisciplinary workshop, unifying diverse perspectives into a coherent framework for advancing black hole research.
• This work is seen as a stepping stone toward developing a quantum theory of gravity, bridging general relativity and quantum mechanics.