English

$\Lambda$CDM model with a scalar perturbation vs. preferred direction of the universe

General Relativity and Quantum Cosmology 2014-11-07 v1 Cosmology and Nongalactic Astrophysics

Abstract

We present a scalar perturbation for the Λ\LambdaCDM model, which breaks the isotropic symmetry of the universe. Based on the Union2 data, the least-χ2\chi^2 fit of the scalar perturbed Λ\LambdaCDM model shows that the universe has a preferred direction (l,b)=(287±25,11±22)(l,b)=(287^\circ\pm25^\circ,11^\circ\pm22^\circ). The magnitude of scalar perturbation is about 2.3×105-2.3\times10^{-5}. The scalar perturbation for the Λ\LambdaCDM model implies a peculiar velocity, which is perpendicular to the radial direction. We show that the maximum peculiar velocities at redshift z=0.15z=0.15 and z=0.015z=0.015 equal to 73±28kms173\pm28 \rm km\cdot s^{-1} and 1099±427kms11099\pm427 \rm km\cdot s^{-1}, respectively. They are compatible with the constraints on peculiar velocity given by Planck Collaboration.

Keywords

Cite

@article{arxiv.1311.3262,
  title  = {$\Lambda$CDM model with a scalar perturbation vs. preferred direction of the universe},
  author = {Xin Li and Hai-Nan Lin and Sai Wang and Zhe Chang},
  journal= {arXiv preprint arXiv:1311.3262},
  year   = {2014}
}

Comments

10 pages, 2 figures