# Lecture Notes on Non-Gaussianity

@inproceedings{Byrnes2014LectureNO, title={Lecture Notes on Non-Gaussianity}, author={Christian T. Byrnes}, year={2014} }

We discuss how primordial non-Gaussianity of the curvature perturbation helps to constrain models of the early universe. Observations are consistent with Gaussian initial conditions, compatible with the predictions of the simplest models of inflation. Deviations are constrained to be at the sub percent level, constraining alternative models such as those with multiple fields, non-canonical kinetic terms or breaking the slow-roll conditions. We introduce some of the most important models of…

## 13 Citations

### More on the Non-Gaussianity of Perturbations in a Nonminimal Inflationary Model

- PhysicsAdvances in High Energy Physics
- 2018

We study nonlinear cosmological perturbations and their possible non-Gaussian character in an extended nonminimal inflation where gravity is coupled nonminimally to both the scalar field and its…

### Consistency relation and non-Gaussianity in a Galileon inflation

- Physics
- 2016

We study a particular Galileon inflation in the light of Planck2015 observational data in order to constraint the model parameter space. We study the spectrum of the primordial modes of the density…

### Testing an Inflation Model with Nonminimal Derivative Coupling in the Light of PLANCK 2015 Data

- Physics
- 2015

We study the dynamics of a generalized inflationary model in which both the scalar field and its derivatives are coupled with the gravity. We consider a general form of the nonminimal derivative…

### Non-Gaussianities and tensor-to-scalar ratio in non-local R2-like inflation

- PhysicsJournal of High Energy Physics
- 2020

In this paper we will study R2-like inflation in a non-local modification of gravity which contains quadratic in Ricci scalar and Weyl tensor terms with analytic infinite derivative form-factors in…

### Non-Gaussianity in multiple three-form field inflation

- Physics
- 2016

In this work, we present a method for implementing the $\delta N$ formalism to study the primordial non-Gaussianity produced in multiple three-form field inflation. Using a dual description relating…

### C O ] 2 1 D ec 2 01 5 Consistently violating the non-Gaussian consistency relation

- Physics
- 2015

Non-attractor models of inflation are characterized by the super-horizon evolution of curvature perturbations, introducing a violation of the non-Gaussian consistency relation between the…

### Non-Gaussianities in generalized non-local $R^2$-like inflation

- Physics
- 2022

: In [1], a most general higher curvature non-local gravity action admitting R 2 -like inﬂationary solution predicting scalar spectral index n s ( N ) ≈ 1 − 2 N , where N is the number of e-folds…

### Initial clustering and the primordial black hole merger rate

- PhysicsJournal of Cosmology and Astroparticle Physics
- 2020

If the primordial curvature perturbation followed a Gaussian distribution, primordial black holes (PBHs) will be Poisson distributed with no additional clustering. We consider local non-Gaussianity…

### The Observational Status of Cosmic Inflation after Planck

- Physics
- 2015

The observational status of inflation after the Planck 2013 and 2015 results and the BICEP2/Keck Array and Planck joint analysis is discussed. These pedagogical lecture notes are intended to serve as…

### Inflaton candidates: from string theory to particle physics

- Physics
- 2018

Cosmic inflation is the cornerstone of modern cosmology. In particular, following the Planck mission reports presented in 2015 regarding cosmic microwave background (CMB), there is an increasing…

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