https://doi.org/10.1140/epjc/s10052-013-2653-x
Regular Article - Theoretical Physics
ΛCDM model with a scalar perturbation vs. preferred direction of the universe
Institute of High Energy Physics, Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, 100049, Beijing, China
* e-mail: lixin@ihep.ac.cn
Received:
6
September
2013
Revised:
22
October
2013
Published online:
28
November
2013
We present a scalar perturbation for the ΛCDM model, which breaks the isotropic symmetry of the universe. Based on the Union2 data, the least-χ 2 fit of the scalar perturbed ΛCDM model shows that the universe has a preferred direction (l,b)=(287∘±25∘,11∘±22∘). The magnitude of scalar perturbation is about −2.3×10−5. The scalar perturbation for the ΛCDM model implies a peculiar velocity, which is perpendicular to the radial direction. We show that the maximum peculiar velocities at redshift z=0.15 and z=0.015 equal to 73±28 km s−1 and 1099±427 km s−1, respectively. They are compatible with the constraints on the peculiar velocity given by the Planck Collaboration.
© Springer-Verlag Berlin Heidelberg and Società Italiana di Fisica, 2013
