Foiling Black Hole Foils: Revealing Horizon Alternatives with Baryonic Atmospheres
Shokoufe Faraji, Avery E. Broderick

TL;DR
This paper demonstrates that horizonless black hole alternatives, or foils, develop observable baryonic atmospheres that produce thermal emissions, providing a way to distinguish them from true black holes through astrophysical observations.
Contribution
It shows that horizonless black hole models naturally form optically thick baryonic atmospheres, which produce observable thermal emissions, challenging the viability of such models as black hole mimickers.
Findings
Baryonic atmospheres form around horizonless foils in accreting systems.
The emergent luminosity is driven toward equilibrium and weakly depends on redshift.
Atmospheres are convectively stable and form at modest redshift even with extreme surface redshift.
Abstract
Event horizons are a defining feature of black holes. Consequently, there have been many efforts to probe their existence in astrophysical black hole candidates, spanning ten orders of magnitude in mass. Nevertheless, horizons remain an obstacle to unifying general relativity and quantum mechanics, most sharply presented by the information paradox. This has motivated a proliferation of horizonless alternatives (black hole foils) that avoid event horizons and are therefore benign. We show that for typical accreting astronomical targets, largely independent of a foil's underlying microphysics, a horizonless compact surface will generically be ensconced within an optically thick, scattering dominated baryonic settling layer that efficiently reprocesses the kinetic energy of infalling matter into observable thermal emission. The emergent photosphere luminosity is driven toward the…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsAstrophysical Phenomena and Observations · Pulsars and Gravitational Waves Research · Relativity and Gravitational Theory
