Phantom damping of matter perturbations
Abstract
Cosmological scaling solutions are particularly important in solving the coincidence problem of dark energy. We derive the equations of subHubble linear matter perturbations for a general scalarfield Lagrangian—including quintessence, tachyon, dilatonic ghost condensate and kessence—and solve them analytically for scaling solutions. We find that matter perturbations are always damped if a phantom field is coupled to dark matter and identify the cases in which the gravitational potential is constant. This provides an interesting possibility to place stringent observational constraints on scaling dark energy models.
 Publication:

Physics Letters B
 Pub Date:
 January 2006
 DOI:
 10.1016/j.physletb.2005.10.065
 arXiv:
 arXiv:astroph/0506222
 Bibcode:
 2006PhLB..632..155A
 Keywords:

 98.80.k;
 Cosmology;
 Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 4 pages, 1 eps figure