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Ultra High Energy Cosmic Rays and de Sitter Vacua

Gian Luigi Alberghi·Kevin Goldstein·David A. Lowe
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Abstract

The production of ultra high-energy cosmic rays in de Sitter invariant vacuum states is considered. Assuming the present-day universe is asymptoting toward a future de Sitter phase, we argue the observed flux of cosmic rays places a bound on the parameter $α$ that characterizes these de Sitter invariant vacuum states, generalizing earlier work of Starobinsky and Tkachev. If this bound is saturated, we obtain a new top-down scenario for the production of super-GZK cosmic rays. The observable predictions bear many similarities to the previously studied scenario where super-GZK events are produced by decay of galactic halo super-heavy dark matter particles.

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Gian Luigi Alberghi, Kevin Goldstein, David A. Lowe. 2003-12-02. Ultra High Energy Cosmic Rays and de Sitter Vacua. https://doi.org/10.1016/j.physletb.2003.10.088

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