# Monodromy Inflation in the Strong Coupling Regime of the Effective Field Theory

## Abstract

We present a simple effective field theory formulation of a general family of single-field flux monodromy models for which strong coupling effects at large field values can flatten the potential and activate higher-derivative operators. Both of these effects can suppress the tensor amplitude. These models are radiatively and nonperturbatively stable and can sustain ≳ 60 e folds of inflation. The dynamics combines features of both large-field chaotic inflation and k inflation. Reducing the tensor-scalar ratio below the observational bound r ≲ 0.1 while keeping the scalar spectral index n _{s} within experimental bounds either yields equilateral non-Gaussianity f ^{ $\underset{\mathrm{NL}}{\overset{}{eq}}$} ≃ O(1) , close to the current observational bounds, or gives very small r .

- Authors:

- Publication Date:

- Research Org.:
- Brandeis Univ., Waltham, MA (United States); Univ. of California, Davis, CA (United States)

- Sponsoring Org.:
- USDOE Office of Science (SC)

- OSTI Identifier:
- 1467761

- Alternate Identifier(s):
- OSTI ID: 1502070

- Grant/Contract Number:
- SC0009999; SC0009987

- Resource Type:
- Published Article

- Journal Name:
- Physical Review Letters

- Additional Journal Information:
- Journal Name: Physical Review Letters Journal Volume: 121 Journal Issue: 9; Journal ID: ISSN 0031-9007

- Publisher:
- American Physical Society (APS)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTRONOMY AND ASTROPHYSICS

### Citation Formats

```
D’Amico, Guido, Kaloper, Nemanja, and Lawrence, Albion. Monodromy Inflation in the Strong Coupling Regime of the Effective Field Theory. United States: N. p., 2018.
Web. doi:10.1103/PhysRevLett.121.091301.
```

```
D’Amico, Guido, Kaloper, Nemanja, & Lawrence, Albion. Monodromy Inflation in the Strong Coupling Regime of the Effective Field Theory. United States. doi:10.1103/PhysRevLett.121.091301.
```

```
D’Amico, Guido, Kaloper, Nemanja, and Lawrence, Albion. Thu .
"Monodromy Inflation in the Strong Coupling Regime of the Effective Field Theory". United States. doi:10.1103/PhysRevLett.121.091301.
```

```
@article{osti_1467761,
```

title = {Monodromy Inflation in the Strong Coupling Regime of the Effective Field Theory},

author = {D’Amico, Guido and Kaloper, Nemanja and Lawrence, Albion},

abstractNote = {We present a simple effective field theory formulation of a general family of single-field flux monodromy models for which strong coupling effects at large field values can flatten the potential and activate higher-derivative operators. Both of these effects can suppress the tensor amplitude. These models are radiatively and nonperturbatively stable and can sustain ≳ 60 e folds of inflation. The dynamics combines features of both large-field chaotic inflation and k inflation. Reducing the tensor-scalar ratio below the observational bound r ≲ 0.1 while keeping the scalar spectral index ns within experimental bounds either yields equilateral non-Gaussianity feqNL ≃ O(1) , close to the current observational bounds, or gives very small r .},

doi = {10.1103/PhysRevLett.121.091301},

journal = {Physical Review Letters},

number = 9,

volume = 121,

place = {United States},

year = {2018},

month = {8}

}

DOI: 10.1103/PhysRevLett.121.091301

*Citation information provided by*

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Web of Science

#### Figures / Tables:

*n*

_{s}−

*r*plane for the ΛCDM model for

*V*

_{eff}∼ $\phi$

^{p}, with

*p*’s listed in the legend, and a quartic kinetic term. The solid lines denote

*c*

_{s}= 1; the dashed lines

*c*

_{s}= 0.6. The colored circles denote normalizations at 50more »

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*Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.*