Spherical collapse of dark energy with an arbitrary sound speed

@article{Basse2011SphericalCO,
  title={Spherical collapse of dark energy with an arbitrary sound speed},
  author={Tobias Basse and Ole Eggers Bjaelde and Yvonne Y. Y. Wong},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2011},
  volume={2011},
  pages={038-038}
}
We consider a generic type of dark energy fluid, characterised by a constant equation of state parameter w and sound speed cs, and investigate the impact of dark energy clustering on cosmic structure formation using the spherical collapse model. Along the way, we also discuss in detail the evolution of dark energy perturbations in the linear regime. We find that the introduction of a finite sound speed into the picture necessarily induces a scale-dependence in the dark energy clustering, which… Expand

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