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Updated: May 24, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Axion dark matter and cosmological parameters
1Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
Abstract:
We observe that photon cooling after big bang nucleosynthesis but before recombination can remove the conflict between the observed and theoretically predicted value of the primordial abundance of ^{7}Li. Such cooling is ordinarily difficult to achieve. However, the recent realization that dark matter axions form a Bose-Einstein condensate provides a possible mechanism because the much colder axions may reach thermal contact with the photons. This proposal predicts a high effective number of neutrinos as measured by the cosmic microwave anisotropy spectrum.
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