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Effective perfect fluids in cosmology

3 Pith papers cite this work, alongside 34 external citations. Polarity classification is still indexing.

3 Pith papers citing it
34 external citations · Pith
abstract

We describe the cosmological dynamics of perfect fluids within the framework of effective field theories. The effective action is a derivative expansion whose terms are selected by the symmetry requirements on the relevant long-distance degrees of freedom, which are identified with comoving coordinates. The perfect fluid is defined by requiring invariance of the action under internal volume-preserving diffeomorphisms and general covariance. At lowest order in derivatives, the dynamics is encoded in a single function of the entropy density that characterizes the properties of the fluid, such as the equation of state and the speed of sound. This framework allows a neat simultaneous description of fluid and metric perturbations. Longitudinal fluid perturbations are closely related to the adiabatic modes, while the transverse modes mix with vector metric perturbations as a consequence of vorticity conservation. This formalism features a large flexibility which can be of practical use for higher order perturbation theory and cosmological parameter estimation.

years

2026 3

representative citing papers

A solid unification of the dark sector

astro-ph.CO · 2026-06-25 · unverdicted · novelty 6.0

A generalized Chaplygin-type solid unifies dark matter and dark energy via an early pressureless phase transitioning to a late solid phase that supports acceleration and produces distinct low-redshift perturbation signatures.

Non-minimal fluid Lagrangian couplings

gr-qc · 2026-05-15 · unverdicted · novelty 5.0

Derives modified Einstein and fluid equations for non-minimal matter-Lagrangian-curvature couplings and demonstrates non-equivalence of Schutz and Brown fluid formulations.

Effective Field Theories for Material Media

hep-th · 2026-07-07 · accept · novelty 4.0

Spacetime-symmetry-breaking Goldstone EFTs systematically describe bulk and localized excitations of solids, fluids, and superfluids, with new thermodynamic identifications and corrected scattering rates.

citing papers explorer

Showing 3 of 3 citing papers.

  • A solid unification of the dark sector astro-ph.CO · 2026-06-25 · unverdicted · none · ref 55 · internal anchor

    A generalized Chaplygin-type solid unifies dark matter and dark energy via an early pressureless phase transitioning to a late solid phase that supports acceleration and produces distinct low-redshift perturbation signatures.

  • Non-minimal fluid Lagrangian couplings gr-qc · 2026-05-15 · unverdicted · none · ref 21 · internal anchor

    Derives modified Einstein and fluid equations for non-minimal matter-Lagrangian-curvature couplings and demonstrates non-equivalence of Schutz and Brown fluid formulations.

  • Effective Field Theories for Material Media hep-th · 2026-07-07 · accept · none · ref 170 · internal anchor

    Spacetime-symmetry-breaking Goldstone EFTs systematically describe bulk and localized excitations of solids, fluids, and superfluids, with new thermodynamic identifications and corrected scattering rates.