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arXiv · 2507.00785

A Non-Inflationary Axion and ALP Misalignment Mechanism

Robert Brandenberger
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Abstract

Based on considerations of quantum gravity, global symmetries which lead to axions as pseudo Nambu-Goldstone bosons after low scale symmetry breaking cannot be exact at the Planck scale. Here, we show that Planck-suppressed terms which yield this symmetry breaking may provide a non-inflationary misalignment mechanism which can generate coherent oscillations of the axion and axion-like particle (ALP) fields at low temperatures.

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Robert Brandenberger. 2025-07-01. A Non-Inflationary Axion and ALP Misalignment Mechanism. https://arxiv.org/abs/2507.00785

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