English

A scaling invariance of the perturbations in $k$-inflation models

General Relativity and Quantum Cosmology 2025-04-21 v2 Cosmology and Nongalactic Astrophysics

Abstract

We study the background and perturbations in kk-essence inflation models and show that a general kk-essence exhibits a simple scaling property. In particular, we study two classes of kk-inflation models with the potential characterized by an inflection point. We demonstrate that these models enjoy scaling properties that could be used to redefine input parameters so that the perturbation spectra satisfy correct normalization at the CMB pivot scale. The background and perturbation equations are integrated numerically for two specific models.

Keywords

Cite

@article{arxiv.2502.06456,
  title  = {A scaling invariance of the perturbations in $k$-inflation models},
  author = {Neven Bilić and Dragoljub D. Dimitrijević and Goran S. Djordjevic and Milan Milošević and Marko Stojanović},
  journal= {arXiv preprint arXiv:2502.06456},
  year   = {2025}
}

Comments

21 pages, 2 figures, 1 table, major revision, Introduction and Sec. 4.4 expanded, one figure added, 13 references added, typos corrected, accepted for publication in Universe