Resurrecting power law inflation in the light of Planck results
Abstract
It is well known that a canonical scalar field with an exponential potential can drive power law inflation (PLI). However, the tensortoscalar ratio in such models turns out to be larger than the stringent limit set by recent Planck results. We propose a new model of power law inflation for which the scalar spectra index, the tensortoscalar ratio and the nongaussianity parameter f{sub N{sub L}{sup equil}} are in excellent agreement with Planck results. Inflation, in this model, is driven by a noncanonical scalar field with an inverse power law potential. The Lagrangian for our model is structurally similar to that of a canonical scalar field and has a power law form for the kinetic term. A simple extension of our model resolves the graceful exit problem which usually afflicts models of power law inflation.
 Authors:
 School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram 695016 (India)
 InterUniversity Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007 (India)
 Publication Date:
 OSTI Identifier:
 22369959
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; 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; LAGRANGIAN FUNCTION; SCALAR FIELDS; SCALARS; SPECTRA; TENSORS; COSMOLOGICAL INFLATION
Citation Formats
Unnikrishnan, Sanil, and Sahni, Varun, Email: sanil@iisertvm.ac.in, Email: varun@iucaa.ernet.in. Resurrecting power law inflation in the light of Planck results. United States: N. p., 2013.
Web. doi:10.1088/14757516/2013/10/063.
Unnikrishnan, Sanil, & Sahni, Varun, Email: sanil@iisertvm.ac.in, Email: varun@iucaa.ernet.in. Resurrecting power law inflation in the light of Planck results. United States. doi:10.1088/14757516/2013/10/063.
Unnikrishnan, Sanil, and Sahni, Varun, Email: sanil@iisertvm.ac.in, Email: varun@iucaa.ernet.in. 2013.
"Resurrecting power law inflation in the light of Planck results". United States.
doi:10.1088/14757516/2013/10/063.
@article{osti_22369959,
title = {Resurrecting power law inflation in the light of Planck results},
author = {Unnikrishnan, Sanil and Sahni, Varun, Email: sanil@iisertvm.ac.in, Email: varun@iucaa.ernet.in},
abstractNote = {It is well known that a canonical scalar field with an exponential potential can drive power law inflation (PLI). However, the tensortoscalar ratio in such models turns out to be larger than the stringent limit set by recent Planck results. We propose a new model of power law inflation for which the scalar spectra index, the tensortoscalar ratio and the nongaussianity parameter f{sub N{sub L}{sup equil}} are in excellent agreement with Planck results. Inflation, in this model, is driven by a noncanonical scalar field with an inverse power law potential. The Lagrangian for our model is structurally similar to that of a canonical scalar field and has a power law form for the kinetic term. A simple extension of our model resolves the graceful exit problem which usually afflicts models of power law inflation.},
doi = {10.1088/14757516/2013/10/063},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2013,
place = {United States},
year = 2013,
month =
}

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