Preheating after multifield inflation with nonminimal couplings. I. Covariant formalism and attractor behavior

Journal Article · 26 January 2018 · Physical Review. D.

DOI: https://doi.org/10.1103/physrevd.97.023526 · OSTI ID:1505817

DeCross, Matthew P. ^[1]; Kaiser, David I. ^[1]; Prabhu, Anirudh ^[1]; Prescod-Weinstein, Chanda ^[2]; Sfakianakis, Evangelos I. ^[3]

---

1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics
2. Univ. of Washington, Seattle, WA (United States). Dept. of Physics
3. Univ. of Illinois, Urbana, IL (United States). Dept. of Physics

This is the first of a three-part series of papers, in which we study the preheating phase for multifield models of inflation involving nonminimal couplings. We study the single-field attractor behavior that these models exhibit during inflation and quantify its strength and parameter dependence. We further demonstrate that the strong single-field attractor behavior persists after the end of inflation. Preheating in such models therefore generically avoids the “dephasing” that typically affects multifield models with minimally coupled fields, allowing efficient transfer of energy from the oscillating inflaton condensate(s) to coupled perturbations across large portions of parameter space. We develop a doubly covariant formalism for studying the preheating phase in such models and identify several features specific to multifield models with nonminimal couplings, including effects that arise from the nontrivial field-space manifold. In papers II and III, we apply this formalism to study how the amplification of adiabatic and isocurvature perturbations varies with parameters, highlighting several distinct regimes depending on the magnitude of the nonminimal couplings $${{\xi}}_{I}$$.

• Research Organization: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP); USDOE
• Grant/Contract Number: SC0012567
• OSTI ID: 1505817
• Alternate ID(s): OSTI ID: 1418191
• Journal Information: Physical Review. D., Vol. 97, Issue 2; ISSN 2470-0010
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English