Perspectives Recent Cosmic Microwave Background data

Wilson discovered the cosmic microwave background (CMB) and found the intensity in different directions to vary by less than 10%. The CMB describes the electro-magnetic energy at microwave frequencies (1 to 100 GHz) pouring in from the cosmos in all directions. This energy can be uniquely described in terms of the temperature of an ideal radiator, called a ‘black body’, that produces radiation at the same frequencies and intensity. In 1977, Smoot and others detected a system of ‘hot ’ and ‘cold ’ patches across the sky in the microwave spectrum.1 A two-dimensional map, as shown in Figure 1, was the result. If one points one’s radiometer (a device to measure ‘black body ’ radiation temperature) away from the hub of our Milky Way galaxy, a signal with a ‘black body’ radiation temperature of about 2.7 K is observed. Smoot detected a sinusoidal variation in the temperature of the CMB at the 1 part in 103 level.1 This was attributed to the motion of the Earth. In order to resolve intrinsic fluctuations, statistical analyses were needed and fluctuations of the order of 10 mK were extracted.2,3 Later, higher resolution measurements were made by the Boomerang (balloon observations of millimetric extra-galactic radiation and geomagnetics) experiment, which involved a microwave telescope lofted 38 km over Antarctica.4 The CMB itself seems to indicate a preferred frame of reference, which is not inconsistent with the principle of relativity.5 Inertial observers would not be able to distinguish anything about their motion except by com