Curvature Perturbations from First-Order Phase Transitions: Implications to Black Holes and Gravitational Waves
Abstract
Understanding whether primordial black holes form during strong first-order phase transition (FOPT) is a crucial open question in cosmology. We address this using a fully covariant formalism to study cosmological perturbations, highlighting previously overlooked gauge dependencies. We show that non-covariant treatments can overestimate primordial black holes and scalar-induced gravitational waves. Once gauge dependencies are accounted for, both signals are strongly suppressed, with direct implications for the FOPT interpretation of the Pulsar Timing Array signal.
Fields of Study & Subjects
Relativity and Gravitational Theory
Cosmology and Gravitation Theories
Black Holes and Theoretical Physics
Publication details
- Journal / source
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Volume
- 136
- Issue
- 17
- Pages
- 171404–171404
- Publication date
- 11 February 2026
- Language
- EN