Work

The special case of slow-roll attractors in de Sitter: non-Markovian noise and evolution of entanglement entropy

Year: 2025

Type: article

Abstract: We analyse the evolution of the reduced density matrix of inflationary perturbations, coupled to a heavy entropic field via the leading-order term within the Effective Field Theory of Inflation, for two nearly de Sitter backgrounds. We perform a full quantum treatment of the open system and derive a Fokker-Planck equation to describe decoherence and the entanglement structure of the adiabatic perturbations. We find that exotic phenomena, such as recoherence and transient negative growth of entanglement entropy, appearing for the attractor solution, are absent for the non-attractor background. We comment on the relationship of these to the non-Markovian nature of the system. Finally, we generalise to the case where a few e-folds of ultra-slow roll evolution are sandwiched between phases of slow-roll inflation to find its (memory) effects on the curvature perturbation.

Source: Journal of Cosmology and Astroparticle Physics

DOI: 10.1088/1475-7516/2025/04/050

Authors: Suddhasattwa Brahma, Jaime Calderón-Figueroa, Xiancong Luo, David Seery

Institutions: University of Edinburgh, University of Sussex

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,290

Funders: China Scholarship Council, Science and Technology Facilities Council