Details
| Original language | English |
|---|---|
| Article number | 002 |
| Number of pages | 41 |
| Journal | Journal of Cosmology and Astroparticle Physics |
| Volume | 2024 |
| Issue number | 3 |
| Publication status | Published - 5 Mar 2024 |
Abstract
Enhancements of primordial curvature fluctuations in single field inflation often involve departures from attractor trajectories in the phase space. We study enhancement/suppression of primordial fluctuations in one of the simplest models with exact background solutions for arbitrary initial conditions: a single field inflationary model with a piecewise exponential potential. We then present close to exact analytical solutions for primordial fluctuations in a general transition between two slow-roll attractors, valid whether the first slow parameter increases or decreases. The main features in the primordial spectrum are determined by the ratio of exponents of the potential. We also discuss the imprint of such features in the induced GW spectrum. Lastly, we apply the δN formalism to discuss non-Gaussianities and the tail of the probability distribution. We find that while non-Gaussianities are at most o(1) in the case of enhancement, they can be very large in the case of suppression. Our work can be easily generalized to multiple piecewise exponential potentials.
Keywords
- cosmological perturbation theory, inflation, primordial black holes, primordial gravitational waves (theory)
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Astronomy and Astrophysics
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In: Journal of Cosmology and Astroparticle Physics, Vol. 2024, No. 3, 002, 05.03.2024.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - An exact model for enhancing/suppressing primordial fluctuations
AU - Domènech, Guillem
AU - Vargas, Gerson
AU - Vargas, Teófilo
N1 - Funding Information: G.D. is supported by the DFG under the Emmy-Noether program grant no. DO 2574/1-1, project number 496592360. T.V. is supported by the Vice-rectorate for Research and Postgraduate B20131101 and CONCYTEC through the Research Academic grant.
PY - 2024/3/5
Y1 - 2024/3/5
N2 - Enhancements of primordial curvature fluctuations in single field inflation often involve departures from attractor trajectories in the phase space. We study enhancement/suppression of primordial fluctuations in one of the simplest models with exact background solutions for arbitrary initial conditions: a single field inflationary model with a piecewise exponential potential. We then present close to exact analytical solutions for primordial fluctuations in a general transition between two slow-roll attractors, valid whether the first slow parameter increases or decreases. The main features in the primordial spectrum are determined by the ratio of exponents of the potential. We also discuss the imprint of such features in the induced GW spectrum. Lastly, we apply the δN formalism to discuss non-Gaussianities and the tail of the probability distribution. We find that while non-Gaussianities are at most o(1) in the case of enhancement, they can be very large in the case of suppression. Our work can be easily generalized to multiple piecewise exponential potentials.
AB - Enhancements of primordial curvature fluctuations in single field inflation often involve departures from attractor trajectories in the phase space. We study enhancement/suppression of primordial fluctuations in one of the simplest models with exact background solutions for arbitrary initial conditions: a single field inflationary model with a piecewise exponential potential. We then present close to exact analytical solutions for primordial fluctuations in a general transition between two slow-roll attractors, valid whether the first slow parameter increases or decreases. The main features in the primordial spectrum are determined by the ratio of exponents of the potential. We also discuss the imprint of such features in the induced GW spectrum. Lastly, we apply the δN formalism to discuss non-Gaussianities and the tail of the probability distribution. We find that while non-Gaussianities are at most o(1) in the case of enhancement, they can be very large in the case of suppression. Our work can be easily generalized to multiple piecewise exponential potentials.
KW - cosmological perturbation theory
KW - inflation
KW - primordial black holes
KW - primordial gravitational waves (theory)
UR - http://www.scopus.com/inward/record.url?scp=85187524712&partnerID=8YFLogxK
U2 - 10.48550/arXiv.2309.05750
DO - 10.48550/arXiv.2309.05750
M3 - Article
AN - SCOPUS:85187524712
VL - 2024
JO - Journal of Cosmology and Astroparticle Physics
JF - Journal of Cosmology and Astroparticle Physics
SN - 1475-7516
IS - 3
M1 - 002
ER -