Letter | Published:

Origin of the Cosmic Rays

Nature volume 135, page 183 (02 February 1935) | Download Citation



FROM the properties of the kinematic world-models which I have been investigating during the past two and a half years, it can be shown that any unimpeded free particle, at large in inter-galactic space, undergoes acceleration as reckoned by an observer located on any arbitrary nebula, and attains the speed of light at some finite epoch in the experience of that observer. It then decelerates. It can also be shown that at any arbitrary epoch, in any arbitrary domain of inter-galactic space, there will occur some particles possessing velocities arbitrarily close to that of light. If such a particle, of atomic dimensions, happens to undergo a collision during this phase of its trajectory, it will give rise to effects similar to those observed in cosmic ray experiments. I therefore identify the primary agency responsible for cosmic rays with highspeed particles accelerated to the vicinity of the speed of light by the gravitational pull of the rest of the universe1. The arguments required are purely kinematical, and involve no appeal to any specific theory of gravitation, or any arbitrary hypotheses.

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  1. 1.

    cf. and , Z. Phys., 56, 777; 1929.

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  1. 19 Northmoor Road, Oxford. Jan. 11.

    • E. A. MILNE


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