Multiscaling of cosmic microwave background radiation

The multiscaling features of structure functions of cosmic microwave background (CMB) radiation have been studied using the new data available with the resolution of the order of a degree (combined QMAP and Saskatoon CMB radiation maps). It is shown that the scaling exponents of the CMB structure functions in the angular scale interval 0.9-4degrees are nearly identical to those of universal velocity structure functions in fluid turbulence. This indicates a strong connection between fluid turbulence and the origin of the observed CMB angular anisotropy in this interval of scales. Since the atmosphere and foreground radiation give minor contribution to these data the most likely explanation for this finding is primordial turbulence. (C) 2002 Elsevier Science B.V. All rights reserved.