Inflation in a scaleinvariant universe
A scaleinvariant universe can have a period of accelerated expansion at early times: inflation. We use a frameinvariant approach to calculate inflationary observables in a scaleinvariant theory of gravity involving two scalar fields: the spectral indices, the tensortoscalar ratio, the level of isocurvature modes, and nonGaussianity. We show that scale symmetry leads to an exact cancellation of isocurvature modes and that, in the scale symmetry–broken phase, this theory is well described by a single scalarfield theory. Lastly, ee find the predictions of this theory strongly compatible with current observations.
 Authors:

^{[1]}
;
^{[2]}
;
^{[3]}
;
^{[1]}
 Univ. of Oxford, Oxford (United Kingdom)
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 ETH Zurich, Zurich (Switzerland)
 Publication Date:
 Report Number(s):
 FERMILABPUB18079T; arXiv:1802.06069
Journal ID: ISSN 24700010; PRVDAQ; 1655609
 Grant/Contract Number:
 AC0207CH11359
 Type:
 Accepted Manuscript
 Journal Name:
 Physical Review D
 Additional Journal Information:
 Journal Volume: 97; Journal Issue: 12; Journal ID: ISSN 24700010
 Publisher:
 American Physical Society (APS)
 Research Org:
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 Sponsoring Org:
 USDOE Office of Science (SC), High Energy Physics (HEP) (SC25)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTRONOMY AND ASTROPHYSICS
 OSTI Identifier:
 1437397
 Alternate Identifier(s):
 OSTI ID: 1454351
Ferreira, Pedro G., Hill, Christopher T., Noller, Johannes, and Ross, Graham G.. Inflation in a scaleinvariant universe. United States: N. p.,
Web. doi:10.1103/PhysRevD.97.123516.
Ferreira, Pedro G., Hill, Christopher T., Noller, Johannes, & Ross, Graham G.. Inflation in a scaleinvariant universe. United States. doi:10.1103/PhysRevD.97.123516.
Ferreira, Pedro G., Hill, Christopher T., Noller, Johannes, and Ross, Graham G.. 2018.
"Inflation in a scaleinvariant universe". United States.
doi:10.1103/PhysRevD.97.123516.
@article{osti_1437397,
title = {Inflation in a scaleinvariant universe},
author = {Ferreira, Pedro G. and Hill, Christopher T. and Noller, Johannes and Ross, Graham G.},
abstractNote = {A scaleinvariant universe can have a period of accelerated expansion at early times: inflation. We use a frameinvariant approach to calculate inflationary observables in a scaleinvariant theory of gravity involving two scalar fields: the spectral indices, the tensortoscalar ratio, the level of isocurvature modes, and nonGaussianity. We show that scale symmetry leads to an exact cancellation of isocurvature modes and that, in the scale symmetry–broken phase, this theory is well described by a single scalarfield theory. Lastly, ee find the predictions of this theory strongly compatible with current observations.},
doi = {10.1103/PhysRevD.97.123516},
journal = {Physical Review D},
number = 12,
volume = 97,
place = {United States},
year = {2018},
month = {6}
}