Reconstructing the inflaton potential{emdash}an overview

Journal Article · Tue Apr 01 04:00:00 UTC 1997 · Reviews of Modern Physics

DOI:https://doi.org/10.1103/RevModPhys.69.373· OSTI ID:477110

Lidsey, J E ^[1]; Liddle, A R ^[2]; Kolb, E W ^[3]; Copeland, E J; Barreiro, T ^[4]; Abney, M ^[5]

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1. Astronomy Unit, School of Mathematical Sciences, Queen Mary and Westfield College, Mile End Road, London E1 4NS (United Kingdom)
2. Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom)
3. NASA/Fermilab Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)
4. Centre for Theoretical Physics, University of Sussex, Falmer, Brighton BN19QH (United Kingdom)
5. Department of Astronomy and Astrophysics, Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637 (United States)

The authors review the relation between the inflationary potential and the spectra of density waves (scalar perturbations) and gravitational waves (tensor perturbations) produced, with particular emphasis on the possibility of reconstructing the inflaton potential from observations. The spectra provide a potentially powerful test of the inflationary hypothesis; they are not independent but instead are linked by consistency relations reflecting their origin from a single inflationary potential. To lowest order in a perturbation expansion there is a single, now familiar, relation between the tensor spectral index and the relative amplitude of the spectra. The authors demonstrate that there is an infinite hierarchy of such consistency equations, though observational difficulties suggest only the first is ever likely to be useful. They also note that since observations are expected to yield much better information on the scalars than on the tensors, it is likely to be the next-order version of this consistency equation that will be appropriate, not the lowest-order one. If inflation passes the consistency test, one can then confidently use the remaining observational information to constrain the inflationary potential, and the authors survey the general perturbative scheme for carrying out this procedure. Explicit expressions valid to next-lowest order in the expansion are presented. The prospects for future observations{close_quote} reaching the quality required are then briefly assessed and simulated data sets motivated by this outlook are considered. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 477110
• Journal Information: Reviews of Modern Physics, Journal Name: Reviews of Modern Physics Journal Issue: 2 Vol. 69; ISSN 0034-6861; ISSN RMPHAT
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
DENSITY
EXPANSION
GRAVITATIONAL WAVES
INFLATIONARY UNIVERSE
PERTURBATION THEORY
POTENTIALS
REVIEWS
SCALAR FIELDS
TENSORS