Analysis of scalar perturbations in cosmological models with a non-local scalar field

Alexey S Koshelev (1) , Sergey Yu Vernov (2)

1 Theoretische Natuurkunde
2 SINP - D.V. Skobeltsyn Institute of Nuclear Physics

We develop the cosmological perturbations formalism in models with a single non-local scalar field originating from the string field theory description of the rolling tachyon dynamics. We construct the equation for the energy density perturbations of the non-local scalar field in the presence of the arbitrary potential and formulate the local system of equations for perturbations in the linearized model when both simple and double roots of the characteristic equation are present. We carry out the general analysis related to the curvature and entropy perturbations and consider the most specific example of perturbations when important quantities in the model become complex.

Mots clés: 98.80.Jk; 11.10Lm; 11.25.Sq; 95.36.+x

Domaines: Relativité Générale et Cosmologie Quantique [gr-qc]

Alexey S Koshelev, Sergey Yu Vernov. Analysis of scalar perturbations in cosmological models with a non-local scalar field. Classical and Quantum Gravity, 2011, 28 (8), pp.85019. ⟨10.1088/0264-9381/28/8/085019⟩. ⟨hal-00690075⟩