# The inflationary trispectrum

@article{Seery2006TheIT, title={The inflationary trispectrum}, author={David Seery and James E. Lidsey and Martin S. Sloth}, journal={Journal of Cosmology and Astroparticle Physics}, year={2006}, volume={2007}, pages={027 - 027} }

We calculate the trispectrum of the primordial curvature perturbation generated by an epoch of slow-roll inflation in the early universe, and demonstrate that the non-Gaussian signature imprinted at horizon crossing is unobservably small, of order τNL ≲ r/50, where r < 1 is the tensor-to-scalar ratio. Therefore any primordial non-Gaussianity observed in future microwave background experiments is likely to have been synthesized by gravitational effects on superhorizon scales. We discuss the…

## 192 Citations

Non-Gaussianity from the inflationary trispectrum

- Economics
- 2007

We present an estimate for the non-linear parameter τNL, which measures the non-Gaussianity imprinted in the trispectrum of the comoving curvature perturbation, ζ. Our estimate is valid throughout…

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- 2009

Using the covariant formalism, we derive the equations of motion for adiabatic and entropy perturbations at third order in perturbation theory for cosmological models involving two scalar fields. We…

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- 2008

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- 2008

We develop a formalism for studying non-Gaussianity in both curvature and isocurvature perturbations. It is shown that non-Gaussianity in the isocurvature perturbation between dark matter and photons…

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- 2012

If the expansion of the early Universe was not close to de Sitter, the statistical imprints of the primordial density perturbation on the cosmic microwave background can be quite different from those…

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- Physics
- 2013

We present a detailed study of the trispectrum of the curvature perturbation generated within a stable, well defined and predictive theory which comprises an inflationary phase. In this model the…

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We compute the covariant three-point function near horizon-crossing for a system of slowly-rolling scalar fields during an inflationary epoch, allowing for an arbitrary field-space metric. We show…

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