Gauge Backreaction in Standard Model Warm Inflation
Abstract
Standard-Model warm inflation (SMWI) makes QCD the microscopic origin of inflationary dissipation, so the real-time response of the gauge plasma enters the cosmological prediction. We show that a slowly relaxing gauge-helicity response cannot, in general, be absorbed into an effective friction coefficient and must instead remain dynamical. We therefore evolve the quark axial densities and a matched hard-helicity mode, with QCD sphalerons and an effective 2↔3 channel generating both charge transfer and correlated stochastic sources in the full perturbation covariance system. The resulting backreaction is substantial but mainly indirect: gauge-helicity screening can reduce the warm dissipation ratio by an order-one fraction on the strong branch, while the 2↔3 channel contributes only 0.2%−0.7% of the zero-density sphaleron friction directly, shifting the amplitude-normalized trajectory in both ns and rvac. The relevant trajectories, however, lack a parametrically broad hard-soft hierarchy and extend beyond strict linear response. The predictions should therefore be understood within the stated local Gaussian transport closure; a parameter-free Standard-Model (SM) result requires finite-affinity real-time SU(3) drift, susceptibility, and noise kernels.
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BibTeX
@misc{dejrah2026gauge,
title = {{Gauge Backreaction in Standard Model Warm Inflation}},
author = {Rafid H. Dejrah and Anish Ghoshal},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.35756},
eprint = {2609.35756},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.35756},
}
RIS
TY - UNPB
TI - Gauge Backreaction in Standard Model Warm Inflation
AU - Rafid H. Dejrah
AU - Anish Ghoshal
PY - 2026
DA - 2026/09/28
PB - arXiv
DO - 10.48550/arxiv.2609.35756
UR - https://arxiv.org/abs/2609.35756
AB - Standard-Model warm inflation (SMWI) makes QCD the microscopic origin of inflationary dissipation, so the real-time response of the gauge plasma enters the cosmological prediction. We show that a slowly relaxing gauge-helicity response cannot, in general, be absorbed into an effective friction coefficient and must instead remain dynamical. We therefore evolve the quark axial densities and a matched hard-helicity mode, with QCD sphalerons and an effective 2↔3 channel generating both charge transfer and correlated stochastic sources in the full perturbation covariance system. The resulting backreaction is substantial but mainly indirect: gauge-helicity screening can reduce the warm dissipation ratio by an order-one fraction on the strong branch, while the 2↔3 channel contributes only 0.2%−0.7% of the zero-density sphaleron friction directly, shifting the amplitude-normalized trajectory in both n_s and r_vac. The relevant trajectories, however, lack a parametrically broad hard-soft hierarchy and extend beyond strict linear response. The predictions should therefore be understood within the stated local Gaussian transport closure; a parameter-free Standard-Model (SM) result requires finite-affinity real-time SU(3) drift, susceptibility, and noise kernels.
ER -