On the renormalization group perspective of αattractors
Abstract
In this short paper we outline a recipe for the reconstruction of F ( R ) gravity starting from single field inflationary potentials in the Einstein frame. For simple potentials one can compute the explicit form of F ( R ), whilst for more involved examples one gets a parametric form of F ( R ). The F ( R ) reconstruction algorithm is used to study various examples: powerlaw φ {sup n} , exponential and α attractors. In each case it is seen that for large R (corresponding to large value of inflaton field), F ( R ) ∼ R {sup 2}. For the case of α attractors F ( R ) ∼ R {sup 2} for all values of inflaton field (for all values of R ) as α → 0. For generic inflaton potential V (φ), it is seen that if V {sup '}/ V →0 (for some φ) then the corresponding F ( R ) ∼ R {sup 2}. We then study αattractors in more detail using nonperturbative renormalisation group methods to analyse the reconstructed F ( R ). It is seen that α →0 is an ultraviolet stable fixed point of the renormalisation group trajectories.
 Authors:
 Kavli Institute for Theoretical Physics China (KITPC), Key Laboratory of Theoretical Physics, Institute of Theoretical Physics (ITP), Chinese Academy of Sciences CAS, Beijing 100190 (China)
 Publication Date:
 OSTI Identifier:
 22667636
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALGORITHMS; ATTRACTORS; GRAVITATION; INFLATONS; QUANTUM GRAVITY; RENORMALIZATION; TRAJECTORIES; ULTRAVIOLET RADIATION
Citation Formats
Narain, Gaurav, Email: gaunarain@itp.ac.cn. On the renormalization group perspective of αattractors. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/10/032.
Narain, Gaurav, Email: gaunarain@itp.ac.cn. On the renormalization group perspective of αattractors. United States. doi:10.1088/14757516/2017/10/032.
Narain, Gaurav, Email: gaunarain@itp.ac.cn. 2017.
"On the renormalization group perspective of αattractors". United States.
doi:10.1088/14757516/2017/10/032.
@article{osti_22667636,
title = {On the renormalization group perspective of αattractors},
author = {Narain, Gaurav, Email: gaunarain@itp.ac.cn},
abstractNote = {In this short paper we outline a recipe for the reconstruction of F ( R ) gravity starting from single field inflationary potentials in the Einstein frame. For simple potentials one can compute the explicit form of F ( R ), whilst for more involved examples one gets a parametric form of F ( R ). The F ( R ) reconstruction algorithm is used to study various examples: powerlaw φ {sup n} , exponential and α attractors. In each case it is seen that for large R (corresponding to large value of inflaton field), F ( R ) ∼ R {sup 2}. For the case of α attractors F ( R ) ∼ R {sup 2} for all values of inflaton field (for all values of R ) as α → 0. For generic inflaton potential V (φ), it is seen that if V {sup '}/ V →0 (for some φ) then the corresponding F ( R ) ∼ R {sup 2}. We then study αattractors in more detail using nonperturbative renormalisation group methods to analyse the reconstructed F ( R ). It is seen that α →0 is an ultraviolet stable fixed point of the renormalisation group trajectories.},
doi = {10.1088/14757516/2017/10/032},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2017,
place = {United States},
year = 2017,
month =
}

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