Sky maps without anisotropies in the cosmic microwave background are a better fit to WMAP's uncalibrated time ordered data than the official sky maps

TL;DR

Reanalyzing WMAP's uncalibrated data shows that sky maps assuming no anisotropies fit the data better than the official maps, raising questions about the detection of cosmic microwave background anisotropies.

Contribution

This study introduces a null hypothesis test allowing calibration variability, revealing that anisotropy-free sky maps better match the raw data than official maps.

Findings

No anisotropy sky maps fit the data better than official maps

Calibration variability affects anisotropy detection

Results challenge the reliability of WMAP's anisotropy claims

Abstract

The purpose of this reanalysis of the WMAP uncalibrated time ordered data (TOD) was two fold. The first was to reassess the reliability of the detection of the anisotropies in the official WMAP sky maps of the cosmic microwave background (CMB). The second was to assess the performance of a proposed criterion in avoiding systematic error in detecting a signal of interest. The criterion was implemented by testing the null hypothesis that the uncalibrated TOD was consistent with no anisotropies when WMAP's hourly calibration parameters were allowed to vary. It was shown independently for all 20 WMAP channels that sky maps with no anisotropies were a better fit to the TOD than those from the official analysis. The recently launched Planck satellite should help sort out this perplexing result.