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Domain Walls as Dark Energy

Alexander Friedland·Hitoshi Murayama·Maxim Perelstein
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Abstract

The possibility that the energy density of the Universe is dominated by a network of low-tension domain walls provides an alternative to the commonly discussed cosmological constant and scalar-field quintessence models of dark energy. We quantify the lower bound on the number density of the domain walls that follows from the observed near-isotropy of the cosmic microwave background radiation. This bound can be satisfied by a strongly frustrated domain wall network. No fine-tuning of the parameters of the underlying field theory model is required. We briefly outline the observational consequences of this model.

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Alexander Friedland, Hitoshi Murayama, Maxim Perelstein. 2003-01-16. Domain Walls as Dark Energy. https://doi.org/10.1103/physrevd.67.043519

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