Non-Perturbative Modulus Decay and Multi-Component Dark Matter
Abstract
Non-thermal cosmological histories rest on the assumption that scalars displaced during inflation undergo coherent oscillations, dominate the energy density of the universe before Big Bang Nucleosynthesis, and decay perturbatively through gravitationally suppressed interactions. In addition, usually a single dark matter component is assumed. This early matter-dominated era is the basis for the usual predictions of non-thermal WIMP production, axion dark matter, entropy generation, and dark radiation. This paper examines whether this picture is dynamically robust against non-perturbative decay of the modulus condensate. In this work, we study non-perturbative particle production from oscillating moduli using the effective field theory appropriate to G2 compactifications. We find that non-perturbative production of Wino-like fermions is strongly suppressed in the relevant parameter regime. In contrast, a modulus-dependent axion kinetic term admits narrow instability bands with growth rates that can exceed the Hubble rate. A linear Floquet analysis alone, however, cannot determine whether these bands significantly deplete the modulus condensate, since cosmic expansion, backreaction, rescattering, and higher-order operators in the effective theory can become important. As a result, the conventional modulus-dominated cosmology remains robust against Wino and gauge-field preheating, while the axion channel provides a potentially important modification that requires nonlinear study. If sufficiently efficient, axion production can alter the division of dark matter between Winos and axions and enhance the dark-radiation abundance.
Related
- A full chemical network treatment of supermassive black hole seed formation from dark matter annihilation or decay
- MeV dark matter decay forecasts for the COSI mission
- Two-Component Dark Matter and Strongly First-Order Electroweak Phase Transition via a Two-Step Mechanism in the Inert Doublet plus Real Singlet Model
- Constraints with CMB lensing on dark matter decays to massive decay products
- Raising the Optical Depth to Reionization with Dark Matter Decay
BibTeX
@misc{kane2026nonperturbative,
title = {{Non-Perturbative Modulus Decay and Multi-Component Dark Matter}},
author = {Gordon Kane and Leia Price and Luis Rufino and Scott Watson and Fred Adams},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.22438},
eprint = {2609.22438},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.22438},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Non-Perturbative Modulus Decay and Multi-Component Dark Matter
AU - Gordon Kane
AU - Leia Price
AU - Luis Rufino
AU - Scott Watson
AU - Fred Adams
PY - 2026
DA - 2026/09/18
PB - arXiv
DO - 10.48550/arxiv.2609.22438
UR - https://arxiv.org/abs/2609.22438
AB - Non-thermal cosmological histories rest on the assumption that scalars displaced during inflation undergo coherent oscillations, dominate the energy density of the universe before Big Bang Nucleosynthesis, and decay perturbatively through gravitationally suppressed interactions. In addition, usually a single dark matter component is assumed. This early matter-dominated era is the basis for the usual predictions of non-thermal WIMP production, axion dark matter, entropy generation, and dark radiation. This paper examines whether this picture is dynamically robust against non-perturbative decay of the modulus condensate. In this work, we study non-perturbative particle production from oscillating moduli using the effective field theory appropriate to G_2 compactifications. We find that non-perturbative production of Wino-like fermions is strongly suppressed in the relevant parameter regime. In contrast, a modulus-dependent axion kinetic term admits narrow instability bands with growth rates that can exceed the Hubble rate. A linear Floquet analysis alone, however, cannot determine whether these bands significantly deplete the modulus condensate, since cosmic expansion, backreaction, rescattering, and higher-order operators in the effective theory can become important. As a result, the conventional modulus-dominated cosmology remains robust against Wino and gauge-field preheating, while the axion channel provides a potentially important modification that requires nonlinear study. If sufficiently efficient, axion production can alter the division of dark matter between Winos and axions and enhance the dark-radiation abundance.
ER -