Upper Limits on Universal Microwave Radiation below λ = 1.7 mm

Abstract

THE microwave radiation discovered by Penzias and Wilson¹ fitted into the theory of the big-bang universe proposed by Gamow² and Dicke et al.³, which predicts a residual radiation with a temperature of ∼ 3° K from the cooling of the primordial radiation. Measurement of the strength of the microwave radiation at different wavelengths⁴ and the inferred strength at 2.3 mm fitted the blackbody curve with a temperature of 2.7° K (Fig. 1). Supporters of the steady state universe^5,6, however, are contesting this interpretation and suggest that the radiation may be the result of the superposition of “sources” or the scattering of source radiation by “dust grains”. At present, there are no direct experimental measurements of microwave radiation below a wavelength of 7 mm to show that the radiation is either a blackbody radiation of temperature 2.7° K or the type predicted by Narlikar and Wickramasinghe⁶. In this report I shall derive upper limits on the intensity of the microwave radiation below a wavelength of 1.7 mm using cosmic ray data to indicate the nature of the radiation.