Absence of significant cross-correlation between WMAP and SDSS

Understand

AIMS.

• Several authors have claimed to detect a significant cross-correlation between microwave WMAP anisotropies and the SDSS galaxy distribution.
• We repeat these analyses to determine the different cross-correlation uncertainties caused by re-sampling errors and field-to-field fluctuations.
• The first type of error concerns overlapping sky regions, while the second type concerns non-overlapping sky regions.