The Cosmic Microwave Background Radiation (CMB) is observed to have a present day temperature of T = 2.725 K. In addition, the CMB is observed to have small temperature fluctuations (hot- and...

The Cosmic Microwave Background Radiation (CMB) is observed to have a present day temperature of T = 2.725 K. In addition, the CMB is observed to have small temperature fluctuations (hot- and cold-spots) superimposed upon it at a relative level of 10−4 . Explain the origin of these fluctuations