A dipole anisotropy of galaxy distribution: Does the CMB rest-frame exist in the local universe?

Abstract

The peculiar motion of the Earth causes a dipole anisotropy modulation in the distant galaxy distribution due to the aberration effect. However, the amplitude and angular direction of the effect is not necessarily the same as those of the cosmic microwave background (CMB) dipole anisotropy due to the growth of cosmic structures. In other words exploring the aberration effect may give us a clue to the horizon-scale physics perhaps related to the cosmic acceleration. In this paper we develop a method to explore the dipole angular modulation from the pixelized galaxy data on the sky properly taking into account the covariances due to the shot noise and the intrinsic galaxy clustering contamination as well as the partial sky coverage. We applied the method to the galaxy catalogs constructed from the Sloan Digital Sky Survey (SDSS) Data Release 6 data. After constructing the four galaxy catalogs that are different in the ranges of magnitudes and photometric redshifts to study possible systematics, we found that the most robust sample against systematics indicates no dipole anisotropy in the galaxy distribution. This finding is consistent with the expectation from the concordance Lambda-dominated cold dark matter model. Finally we argue that an almost full-sky galaxy survey such as LSST may allow for a significant detection of the aberration effect of the CMB dipole having the precision of constraining the angular direction to ~ 20 degrees in radius. Assuming a hypothetical LSST galaxy survey, we find that this method can confirm or reject the result implied from a stacked analysis of the kinetic Sunyaev-Zel'dovich effect of X-ray luminous clusters in Kashlinsky et al. (2008,2009) if the implied cosmic bulk flow is not extended out to the horizon.

20 pages, 11 figures; 24 pages, added a couple of references and 2 figures. Revised version in response to the referee's comments. Resubmitted to Phys. Rev. D

References in corpus (9)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• A new measurement of the bulk flow of X-ray luminous clusters of galaxies
• Probing dark energy with cluster counts and cosmic shear power spectra: including the full covariance
• Can a galaxy redshift survey measure dark energy clustering?
• Detecting the Cosmic Dipole Anisotropy in Large-Scale Radio Surveys
• The PSCz Dipole Revisited
• Photometric Redshifts with Surface Brightness Priors
• Is the misalignment of the Local Group velocity and the 2MASS Redshift Survey dipole typical in a LambdaCDM model?

Cited by in corpus (35)

• Challenges for $\Lambda$CDM: An update
• Planck 2013 results. XXVII. Doppler boosting of the CMB: Eppur si muove
• Dipoles in the Sky
• High redshift radio galaxies and divergence from the CMB dipole
• Probing the Cosmological Principle in the counts of radio galaxies at different frequencies
• Homogeneity and isotropy in the 2MASS Photometric Redshift catalogue
• The Signature of Proper Motion in the Microwave Sky
• Planck intermediate results. XIII. Constraints on peculiar velocities
• The velocity field of 2MRS Ks=11.75 galaxies: constraints on beta and bulk flow from the luminosity function
• Is the 2MASS clustering dipole convergent?
• Dipolar modulation in number counts of WISE-2MASS sources
• Searching for anisotropy in the distribution of binary black hole mergers
• Testing the standard model of cosmology with the SKA: the cosmic radio dipole
• Large scale anisotropy due to pre-inflationary phase of cosmic evolution
• The dipole anisotropy of AllWISE galaxies
• Is there evidence for anomalous dipole anisotropy in the large-scale structure?
• Detected fluctuations in SDSS LRG magnitudes: Bulk flow signature or systematic?
• Direction dependence of the power spectrum and its effect on the Cosmic Microwave Background Radiation
• Probing statistical isotropy of cosmological radio sources using SKA
• Polarization Alignment in JVAS/CLASS flat spectrum radio surveys
• Testing the Cosmological Principle in the radio sky
• Probing the Universe's Tilt with the Cosmic Infrared Background Dipole
• Kinematic dipole detection with galaxy surveys: forecasts and requirements
• Non-comoving Cosmology
• Reconstructing the Primary CMB Dipole
• Tracing the cosmic velocity field at z ~ 0.1 from galaxy luminosities in the SDSS DR7
• The dipole anisotropy of WISE x SuperCOSMOS number counts
• Effect of Foregrounds on the CMBR Multipole Alignment
• Probing the rest-frame of the Universe with near-IR cosmic infrared background
• Probing the Cosmological Principle with the CSST Photometric Survey
• Gravitational Lensing from a Spacetime Perspective
• Measuring our peculiar velocity from spectroscopic redshift surveys
• Distortions in the Surface of Last Scattering
• Motion of the Local Group as a cosmological probe
• The Kaiser-Rocket effect: three decades and counting