Long-wavelength Cosmological Perturbation in the Universe with Multiple Perfect Fluids

TL;DR

This paper develops a Hamilton-Jacobi based method to analyze large-scale cosmological perturbations in a universe with multiple perfect fluids, including applications to brane cosmology.

Contribution

It introduces a new Hamilton-Jacobi approach for gauge-invariant perturbation analysis in multi-fluid cosmologies, extending previous methods.

Findings

Derived a formula for gauge-invariant comoving curvature perturbation.

Applied the method to analyze perturbations in brane cosmology.

Provided insights into large-scale structure formation in complex cosmological models.

Abstract

We investigate the large scale cosmological perturbation in the Universe with multiple perfect fluids. Using the long-wavelength approximation with Hamilton-Jacobi method, we derive the formula for the gauge invariant comoving curvature perturbation. As an application of our approach, we examine the large scale perturbation in a brane cosmology.