Saved in:
Bibliographic Details
Main Authors: Pareek, Pooja, Nautiyal, Akhilesh
Format: Preprint
Published: 2023
Subjects:
Online Access:https://arxiv.org/abs/2306.01576
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916081188208640
author Pareek, Pooja
Nautiyal, Akhilesh
author_facet Pareek, Pooja
Nautiyal, Akhilesh
contents The large value of non-minimal coupling constant $ξ$ required to satisfy CMB observations in Higgs inflation violates unitarity. In this work we study Higgs-inflation with non-canonical kinetic term of DBI form to find whether $ξ$ can be reduced. To study the inflationary dynamics, we transform the action to the Einstein frame, in which the Higgs is minimally coupled to gravity with a non-canonical kinetic term and modified potential. We choose the Higgs self coupling constant $λ=0.14$ for our analysis. We find that the value of $ξ$ can be reduced from $10^{3}-10^{4}$ to $\mathcal{O}(10)$ to satisfy Planck constraints on amplitude of scalar power spectrum. However, this model produces a larger tensor-to-scalar ratio $r$, in comparison to the Higgs inflation with canonical kinetic term. We also find that, to satisfy joint constraints on scalar spectral index $n_s$ and tensor-to-scalar ratio $r$ from Planck-2018 and bounds on $r$ from Planck and BICEP3, the value of $ξ$ should be of the order of $10^4$. Thus, the issue of unitarity violation remains even after considering Higgs inflation with non-canonical kinetic term
format Preprint
id arxiv_https___arxiv_org_abs_2306_01576
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Non-canonical Higgs inflation
Pareek, Pooja
Nautiyal, Akhilesh
Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
High Energy Physics - Theory
The large value of non-minimal coupling constant $ξ$ required to satisfy CMB observations in Higgs inflation violates unitarity. In this work we study Higgs-inflation with non-canonical kinetic term of DBI form to find whether $ξ$ can be reduced. To study the inflationary dynamics, we transform the action to the Einstein frame, in which the Higgs is minimally coupled to gravity with a non-canonical kinetic term and modified potential. We choose the Higgs self coupling constant $λ=0.14$ for our analysis. We find that the value of $ξ$ can be reduced from $10^{3}-10^{4}$ to $\mathcal{O}(10)$ to satisfy Planck constraints on amplitude of scalar power spectrum. However, this model produces a larger tensor-to-scalar ratio $r$, in comparison to the Higgs inflation with canonical kinetic term. We also find that, to satisfy joint constraints on scalar spectral index $n_s$ and tensor-to-scalar ratio $r$ from Planck-2018 and bounds on $r$ from Planck and BICEP3, the value of $ξ$ should be of the order of $10^4$. Thus, the issue of unitarity violation remains even after considering Higgs inflation with non-canonical kinetic term
title Non-canonical Higgs inflation
topic Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
High Energy Physics - Theory
url https://arxiv.org/abs/2306.01576