Abstract:
The scalar and vector cosmological perturbations
at all length scales of our Universe are studied in the framework of the phantom braneworld model. The model is characterized by the parameter M ≡ M3/2m2H0, with M and
m the five- and four-dimensional Planck scales, respectively,
and H0 the Hubble parameter today, while M → 0 recovers the CDM model. Ignoring the backreaction due to the
peculiar velocities and also the bulk cosmological constant,
allows the explicit computation of the gravitational potentials, and . They exhibit exponentially decreasing screening behaviour characterized by a screening length which is a
function of the quasidensity parameter M .
