Seminar

[Seminario]"Teorías efectivas, Física de partículas y Cosmología" por Héctor Villarrubia Rojo

Start date: 19/09/2019 11:30 End date: 19/09/2019 12:00

​"Tilting the dark sector"

One of the fundamental assumptions of the standard $\Lambda$CDM cosmology is that, on large scales, all the matter-energy components of the Universe share a common rest frame. This seems natural for the visible sector, that has been in thermal contact and tightly coupled in the primeval Universe. The dark sector, on the other hand, does not have any non-gravitational interaction known to date and therefore there is no a priori reason to impose that it is comoving with ordinary matter. Our model extends $\Lambda$CDM with the addition of a single free parameter $\beta_0$, the initial velocity of the visible sector with respect to the frame that observes a homogeneous and isotropic universe. This modification gives rise to a rich phenomenology, while being consistent with current observations for $\beta_0<1.6\times 10^{-3}$ (95% CL).

Among the observable effects we find: sizeable modifications in the density-velocity and density-lensing potential cross-correlation spectra for matter, violations of CMB statistical isotropy and production of vorticity and cosmological magnetic fields through new couplings between scalar and vector modes.


  • Centro Mixto perteneciente al Consejo Superior de Investigaciones Científicas (CSIC) y la Universidad de Cantabria (UC)

    Instituto de Física de Cantabria
    Edificio Juan Jordá
    Avenida de los Castros, s/n
    E-39005 Santander
    Cantabria, España

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