Bulk viscosity and $n$-component fluids
Fuente:
arXiv
Saved in:
| Main Author: | |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866908452995989504 |
|---|---|
| author | Säppi, Saga |
| author_facet | Säppi, Saga |
| contents | Understanding the hydrodynamics of out-of-equilibrium dense viscous fluids is of key importance to accurate descriptions of physical systems such as compact stars, particularly their mergers. We consider a near-equilibrium relativistic fluid with $n$ independent and small chemical potentials restoring the system back towards equilibrium. By diagonalising the evolution equation for the out-of-equilibrium chemical potentials, we construct an explicit evolution equation for the bulk scalar of the system in second-order hydrodynamics in terms of equilibrium quantities. We find expressions for the $2n$ transport quantities and show that in the rest frame of the fluid, the system admits a Green's function corresponding to an $n$-component fluid. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2507_12365 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Bulk viscosity and $n$-component fluids Säppi, Saga High Energy Physics - Phenomenology General Relativity and Quantum Cosmology High Energy Physics - Theory Nuclear Theory Understanding the hydrodynamics of out-of-equilibrium dense viscous fluids is of key importance to accurate descriptions of physical systems such as compact stars, particularly their mergers. We consider a near-equilibrium relativistic fluid with $n$ independent and small chemical potentials restoring the system back towards equilibrium. By diagonalising the evolution equation for the out-of-equilibrium chemical potentials, we construct an explicit evolution equation for the bulk scalar of the system in second-order hydrodynamics in terms of equilibrium quantities. We find expressions for the $2n$ transport quantities and show that in the rest frame of the fluid, the system admits a Green's function corresponding to an $n$-component fluid. |
| title | Bulk viscosity and $n$-component fluids |
| topic | High Energy Physics - Phenomenology General Relativity and Quantum Cosmology High Energy Physics - Theory Nuclear Theory |
| url | https://arxiv.org/abs/2507.12365 |