Chaotic inflation from nonlinear sigma models in supergravity
Abstract
We present a common solution to the puzzles of the light Higgs or quark masses and the need for a shift symmetry and large field values in high scale chaotic inflation. One way to protect, for example, the Higgs from a large supersymmetric mass term is if it is the Nambu–Goldstone boson (NGB) of a nonlinear sigma model. However, it is well known that nonlinear sigma models (NLSMs) with nontrivial Kähler transformations are problematic to couple to supergravity. An additional field is necessary to make theKähler potential of the NLSM invariant in supergravity. This field must have a shift symmetry — making it a candidate for the inflaton (or axion). We give an explicit example of such a model for the coset space SU(3)/SU(2) × U(1), with the Higgs as the NGB, including breaking the inflaton’s shift symmetry and producing a chaotic inflation potential. This construction can also be applied to other models, such as one based on E₇/SO(10) × U(1) × U(1) which incorporates the first two generations of (light) quarks as the Nambu–Goldstone multiplets, and has an axion in addition to the inflaton. Along the way we clarify and connect previous work on understanding NLSMs in supergravity andmore »
 Authors:
 The Univ. of Tokyo, Chiba (Japan). Kavli Institute for the Physics and Mathematics of the Universe.
 The Univ. of Tokyo, Chiba (Japan). Kavli Institute for the Physics and Mathematics of the Universe; Vanderbilt Univ., Nashville, TN (United States). Dept. of Physics and Astronomy.
 Publication Date:
 Research Org.:
 Vanderbilt Univ., Nashville, TN (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1197973
 Alternate Identifier(s):
 OSTI ID: 1192107
 Grant/Contract Number:
 SC0011981; 26104009; 26287039
 Resource Type:
 Journal Article: Published Article
 Journal Name:
 Physics Letters. Section B
 Additional Journal Information:
 Journal Volume: 742; Journal Issue: C; Journal ID: ISSN 03702693
 Publisher:
 Elsevier
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS
Citation Formats
Hellerman, Simeon, Kehayias, John, and Yanagida, Tsutomu T. Chaotic inflation from nonlinear sigma models in supergravity. United States: N. p., 2015.
Web. doi:10.1016/j.physletb.2015.02.019.
Hellerman, Simeon, Kehayias, John, & Yanagida, Tsutomu T. Chaotic inflation from nonlinear sigma models in supergravity. United States. doi:10.1016/j.physletb.2015.02.019.
Hellerman, Simeon, Kehayias, John, and Yanagida, Tsutomu T. 2015.
"Chaotic inflation from nonlinear sigma models in supergravity". United States.
doi:10.1016/j.physletb.2015.02.019.
@article{osti_1197973,
title = {Chaotic inflation from nonlinear sigma models in supergravity},
author = {Hellerman, Simeon and Kehayias, John and Yanagida, Tsutomu T.},
abstractNote = {We present a common solution to the puzzles of the light Higgs or quark masses and the need for a shift symmetry and large field values in high scale chaotic inflation. One way to protect, for example, the Higgs from a large supersymmetric mass term is if it is the Nambu–Goldstone boson (NGB) of a nonlinear sigma model. However, it is well known that nonlinear sigma models (NLSMs) with nontrivial Kähler transformations are problematic to couple to supergravity. An additional field is necessary to make theKähler potential of the NLSM invariant in supergravity. This field must have a shift symmetry — making it a candidate for the inflaton (or axion). We give an explicit example of such a model for the coset space SU(3)/SU(2) × U(1), with the Higgs as the NGB, including breaking the inflaton’s shift symmetry and producing a chaotic inflation potential. This construction can also be applied to other models, such as one based on E₇/SO(10) × U(1) × U(1) which incorporates the first two generations of (light) quarks as the Nambu–Goldstone multiplets, and has an axion in addition to the inflaton. Along the way we clarify and connect previous work on understanding NLSMs in supergravity and the origin of the extra field (which is the inflaton here), including a connection to Witten–Bagger quantization. This framework has wide applications to model building; a light particle from a NLSM requires, in supergravity, exactly the structure for chaotic inflaton or an axion},
doi = {10.1016/j.physletb.2015.02.019},
journal = {Physics Letters. Section B},
number = C,
volume = 742,
place = {United States},
year = 2015,
month = 2
}
Web of Science

We present a common solution to the puzzles of the light Higgs or quark masses and the need for a shift symmetry and large field values in high scale chaotic inflation. One way to protect, for example, the Higgs from a large supersymmetric mass term is if it is the Nambu–Goldstone boson (NGB) of a nonlinear sigma model. However, it is well known that nonlinear sigma models (NLSMs) with nontrivial Kähler transformations are problematic to couple to supergravity. An additional field is necessary to make theKähler potential of the NLSM invariant in supergravity. This field must have a shift symmetrymore »Cited by 2

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