English

(Slow-)Twisting inflationary attractors

High Energy Physics - Theory 2023-11-13 v3 Cosmology and Nongalactic Astrophysics

Abstract

We explore in detail the dynamics of multi-field inflationary models. We first revisit the two-field case and rederive the coordinate independent expression for the attractor solution with either small or large turn rate, emphasizing the role of isometries for the existence of rapid-turn solutions. Then, for three fields in the slow-twist regime we provide elegant expressions for the attractor solution for generic field-space geometries and potentials and study the behaviour of first order perturbations. For generic N\mathcal{N}-field models, our method quickly grows in algebraic complexity. We observe that field-space isometries are common in the literature and are able to obtain the attractor solutions and deduce stability for some isometry classes of N\mathcal{N}-field models. Finally, we apply our discussion to concrete supergravity models. These analyses conclusively demonstrate the existence of N>2\mathcal{N}>2 dynamical attractors distinct from the two-field case, and provide tools useful for future studies of their phenomenology in the cosmic microwave background and stochastic gravitational wave spectrum.

Keywords

Cite

@article{arxiv.2210.14900,
  title  = {(Slow-)Twisting inflationary attractors},
  author = {Perseas Christodoulidis and Robert Rosati},
  journal= {arXiv preprint arXiv:2210.14900},
  year   = {2023}
}

Comments

38 pages, 10 figures. v3: improved figures, minor changes

R2 v1 2026-06-28T04:35:14.790Z