Energy extraction from bouncing geometries

• Autor(a) principal: Cardoso, V.
• Data de Publicação: 2023
• Outros Autores: Costa, J. L., Natário, J., Zhong, Z.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10071/29789

Quantum gravity phenomenology suggests the interesting possibility that black holes are not eternal. Collapse could be halted by some unknown mechanism, or Hawking radiation might leave behind a regular spacetime. Here we investigate a simple bouncing geometry, with (outer and inner) apparent horizons but no event horizon. We show that the inner horizon blueshifts radiation, which can lead to a gigantic amplification of energy observable from far away regions. Thus, if such phenomena exist in our Universe, then they can power high-energy bursts at late stages in their lives, when the horizons disappear and spacetime bounces back to a flat geometry.