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How Many e-Folds Should We Expect from High-Scale Inflation?

Remmen, Grant N. and Carroll, Sean M. (2014) How Many e-Folds Should We Expect from High-Scale Inflation? Physical Review D, 90 (6). Art. No. 063517. ISSN 1550-7998. doi:10.1103/PhysRevD.90.063517.

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We address the issue of how many e-folds we would naturally expect if inflation occurred at an energy scale of order 10^(16) GeV. We use the canonical measure on trajectories in classical phase space, specialized to the case of flat universes with a single scalar field. While there is no exact analytic expression for the measure, we are able to derive conditions that determine its behavior. For a quadratic potential V(ϕ)=m^2ϕ^2/2 with m=2×10^(13) GeV and cutoff at M_(Pl)=2.4×10^(18) GeV, we find an expectation value of 2×1010 e-folds on the set of FRW trajectories. For cosine inflation V(ϕ)=Λ^4[1−cos(ϕ/f)] with f=1.5×10^(19) GeV, we find that the expected total number of e-folds is 50, which would just satisfy the observed requirements of our own Universe; if f is larger, more than 50 e-folds are generically attained. We conclude that one should expect a large amount of inflation in large-field models and more limited inflation in small-field (hilltop) scenarios.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Remmen, Grant N.0000-0001-6569-8866
Carroll, Sean M.0000-0002-4226-5758
Additional Information:© 2014 American Physical Society. Received 22 May 2014; published 22 September 2014. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE-1144469, by DOE Grant No. DE-SC0011632, and by the Gordon and Betty Moore Foundation through Grant No. 776 to the Caltech Moore Center for Theoretical Cosmology and Physics. G.N.R. is supported by a Hertz Graduate Fellowship and a NSF Graduate Research Fellowship.
Group:Caltech Theory, Walter Burke Institute for Theoretical Physics, Moore Center for Theoretical Cosmology and Physics
Funding AgencyGrant Number
NSF Graduate Research FellowshipDGE-1144469
Department of Energy (DOE)DE-SC0011632
Gordon and Betty Moore Foundation776
Fannie and John Hertz FoundationUNSPECIFIED
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Issue or Number:6
Classification Code:PACS: 98.80.Cq, 98.80.Jk, 98.80.Bp
Record Number:CaltechAUTHORS:20140529-121305448
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Official Citation:How many e-folds should we expect from high-scale inflation? Grant N. Remmen and Sean M. Carroll Phys. Rev. D 90, 063517 (2014) – Published 22 September 2014
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:45972
Deposited By: Joy Painter
Deposited On:29 May 2014 22:01
Last Modified:10 Nov 2021 17:18

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