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Title: Massive fields as systematics for single field inflation

Abstract

During inflation, massive fields can contribute to the power spectrum of curvature perturbation via a dimension-5 operator. This contribution can be considered as a bias for the program of using n {sub s} and r to select inflation models. Even the dimension-5 operator is suppressed by Λ = M {sub p} , there is still a significant shift on the n {sub s} - r diagram if the massive fields have m ∼ H . On the other hand, if the heavy degree of freedom appears only at the same energy scale as the suppression scale of the dimension-5 operator, then significant shift on the n {sub s} - r diagram takes place at m =Λ ∼ 70 H , which is around the inflationary time-translation symmetry breaking scale. Hence, the systematics from massive fields pose a greater challenge for future high precision experiments for inflationary model selection. This result can be thought of as the impact of UV sensitivity to inflationary observables.

Authors:
;  [1]
  1. Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)
Publication Date:
OSTI Identifier:
22676154
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 06; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; DEGREES OF FREEDOM; DISTURBANCES; FIELD THEORIES; GRAVITATION; INFLATIONARY UNIVERSE; PERTURBATION THEORY; SENSITIVITY; SPECTRA; SYMMETRY BREAKING

Citation Formats

Jiang, Hongliang, and Wang, Yi, E-mail: hjiangag@connect.ust.hk, E-mail: phyw@ust.hk. Massive fields as systematics for single field inflation. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/06/038.
Jiang, Hongliang, & Wang, Yi, E-mail: hjiangag@connect.ust.hk, E-mail: phyw@ust.hk. Massive fields as systematics for single field inflation. United States. doi:10.1088/1475-7516/2017/06/038.
Jiang, Hongliang, and Wang, Yi, E-mail: hjiangag@connect.ust.hk, E-mail: phyw@ust.hk. Thu . "Massive fields as systematics for single field inflation". United States. doi:10.1088/1475-7516/2017/06/038.
@article{osti_22676154,
title = {Massive fields as systematics for single field inflation},
author = {Jiang, Hongliang and Wang, Yi, E-mail: hjiangag@connect.ust.hk, E-mail: phyw@ust.hk},
abstractNote = {During inflation, massive fields can contribute to the power spectrum of curvature perturbation via a dimension-5 operator. This contribution can be considered as a bias for the program of using n {sub s} and r to select inflation models. Even the dimension-5 operator is suppressed by Λ = M {sub p} , there is still a significant shift on the n {sub s} - r diagram if the massive fields have m ∼ H . On the other hand, if the heavy degree of freedom appears only at the same energy scale as the suppression scale of the dimension-5 operator, then significant shift on the n {sub s} - r diagram takes place at m =Λ ∼ 70 H , which is around the inflationary time-translation symmetry breaking scale. Hence, the systematics from massive fields pose a greater challenge for future high precision experiments for inflationary model selection. This result can be thought of as the impact of UV sensitivity to inflationary observables.},
doi = {10.1088/1475-7516/2017/06/038},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2017,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}
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