detalle del documento
IDENTIFICACIÓN
oai:arXiv.org:2411.05393
Tema
Astrophysics - Astrophysics of Gal... Astrophysics - Cosmology and Nonga... General Relativity and Quantum Cos...Autor
Roupas, ZachariasCategoría
ciencias: astrofísica
Año
2024
fecha de cotización
18/12/2024
Palabras clave
expanding background baryonic astrophysicsResumen
Spatially homogeneous thermal equilibria of self-gravitating gas, being impossible otherwise, are nevertheless allowed in an expanding background accounting for Universe's expansion.
Furthermore, a fixed density at the boundary of a perturbation is a natural boundary condition keeping the mass finite inside without the need to invoke any unphysical walls.
These facts allow us to develop a consistent gravitational thermodynamics of isothermal spheres inside an expanding Universe.
In the canonical and grand canonical ensembles we identify an instability for both homogeneous and inhomogeneous equilibria.
We discuss a potential astrophysical application.
If such an instability is triggered on baryonic gas at high redshift $z > 137$ when the primary baryonic component, namely atomic hydrogen, was still thermally locked to the Cosmic Microwave Background radiation, then the corresponding destabilized gaseous clouds have baryonic mass $\geq 0.8\cdot 10^5 {\rm M}_\odot$ and radius $\geq 15{\rm pc}$.
;Comment: to appear in PRD
Roupas, Zacharias, 2024, Self-gravitating isothermal sphere in an expanding background
Clinical Relevance of Plaque Distribution for Basilar Artery Stenosis
study endovascular imaging wall basilar complications plaque postoperative artery plaques stenosis
