Abstract

The subject of ‘cosmic rays’ is one that embraces a vast range of particle and photon energies and is an ideal one for examining ‘Physics and the Cosmos’. In the present work we examine the twin problems of the origin of cosmic rays of both low and very high energies and find that they are related by studies of the Magellanic Clouds. This remarkable result comes from the hypothesis that there is a Giant Halo surrounding the Galaxy, support coming from Magellanic Cloud observations. Also examined is the flux of extragalactic gamma rays and its relevance to the question of the asymmetry between matter and anti-matter in the Universe.