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Related papers: Non-gaussianity from the trispectrum in general si…

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We compute the leading order contribution to the four-point function of the primordial curvature perturbation in a class of single field models where the inflationary Lagrangian is a general function of the inflaton and its first…

High Energy Physics - Theory · Physics 2008-12-04 Xingang Chen , Min-xin Huang , Gary Shiu

We investigate the primordial non-Gaussianities from the trispectra in multi-field inflation models, which can be seen as generalization of multi-field $k$-inflation and multi-DBI inflation. We derive the full fourth-order perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Xian Gao , Miao Li , Chunshan Lin

We compute the large scalar four-point correlation functions in general single field inflation models, where the inflaton Lagrangian is an arbitrary function of the inflaton and its first derivative. We find that the leading order…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Xingang Chen , Bin Hu , Min-xin Huang , Gary Shiu , Yi Wang

We perform the analysis of the trispectrum of curvature perturbations generated by the interactions characterizing a general theory of single-field inflation obtained by effective field theory methods. We find that curvature-generated…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Nicola Bartolo , Matteo Fasiello , Sabino Matarrese , Antonio Riotto

We study the second-order gauge-invariant adiabatic and isocurvature perturbations in terms of the scalar fields present during inflation, along with the related fully non-linear space gradient of these quantities. We discuss the relation…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-01 Eleftheria Tzavara , Bartjan van Tent

Single scalar field inflation with a generic, non-quadratic in derivatives, field Lagrangian is considered. It is shown that non-Gaussianity of curvature perturbations is characterized by two dimensionless amplitudes. One of these…

Astrophysics · Physics 2009-11-10 Andrei Gruzinov

In this paper, we compute the inflationary trispectrum of primordial gauge fields generated through the scalar and tensor exchanges in models with spectator $U(1)$ gauge fields which are kinetically coupled to the inflaton. Focusing on the…

High Energy Physics - Theory · Physics 2025-09-16 P. Jishnu Sai , S. R. Haridev , Rajeev Kumar Jain

We perform a general study of the primordial scalar non-Gaussianities in multi-field inflationary models in Einstein gravity. We consider models governed by a Lagrangian which is a general function of the scalar fields and their first…

Astrophysics · Physics 2009-06-23 Xian Gao

We compute the connected four-point correlation function of the primordial curvature perturbation generated during inflation with standard kinetic terms, where the correlation is established via exchange of a graviton between two pairs of…

Astrophysics · Physics 2010-04-21 David Seery , Martin S. Sloth , Filippo Vernizzi

We compute the bispectrum of primordial density perturbations in CMB to second order in the slow-roll parameters of single field inflation. We correct previous results and found that next-to-leading order corrections can be of the same…

High Energy Physics - Theory · Physics 2026-03-31 Ignatios Antoniadis , Auttakit Chatrabhuti , Jules Cunat , Hiroshi Isono

We study the linear perturbation of the recently proposed model of inflation where a uniform gauge-kinetic coupling of the inflaton to multiple vector fields breaks the cosmic no-hair conjecture while maintaining the isotropy. We derive the…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-09 Kei Yamamoto

The evolution of gauge invariant second-order scalar perturbations in a general single field inflationary scenario are presented. Different second order gauge invariant expressions for the curvature are considered. We evaluate…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Finelli , G. Marozzi , G. P. Vacca , G. Venturi

We present a model of inflation in which the inflaton field is charged under a triplet of $U(1)$ gauge fields. The model enjoys an internal $O(3)$ symmetry supporting the isotropic FRW solution. With an appropriate coupling between the…

High Energy Physics - Theory · Physics 2019-10-08 Hassan Firouzjahi , Mohammad Ali Gorji , Seyed Ali Hosseini Mansoori , Asieh Karami , Tahereh Rostami

We study non-Gaussianities in the primordial perturbations in single field inflation where there is radiation era prior to inflation. Inflation takes place when the energy density of radiation drops below the value of the potential of a…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-30 Suratna Das , Subhendra Mohanty

We study the bispectrum of the curvature perturbation on uniform energy density hypersurfaces in models of inflation with two scalar fields evolving simultaneously. In the case of a separable potential, it is possible to compute the…

Astrophysics · Physics 2009-11-11 Filippo Vernizzi , David Wands

We calculate the trispectrum of curvature perturbations for a model of inflation endowed with Galilean symmetry at the level of the fluctuations around an FRW background. Such a model has been shown to posses desirable properties such as…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Nicola Bartolo , Emanuela Dimastrogiovanni , Matteo Fasiello

We present the first computation of the cosmological perturbations generated during inflation up to second order in deviations from the homogeneous background solution. Our results, which fully account for the inflaton self-interactions as…

Astrophysics · Physics 2010-04-05 V. Acquaviva , N. Bartolo , S. Matarrese , A. Riotto

Inflationary predictions for the power spectrum of the curvature perturbation have been verified to an excellent degree, leaving many models compatible with observations. In this thesis we studied third-order correlations, that might allow…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 Eleftheria Tzavara

We compute the tree-level connected four-point function of the primordial curvature perturbation for a fairly general minimally coupled single field inflationary model, where the inflaton's Lagrangian is a general function of the scalar…

High Energy Physics - Theory · Physics 2010-04-14 Frederico Arroja , Shuntaro Mizuno , Kazuya Koyama , Takahiro Tanaka

Employing an effective field theory approach to inflationary perturbations, we analyze in detail the effect of curvature-generated Lagrangian operators on various observables, focusing on their running with scales. At quadratic order, we…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Nicola Bartolo , Matteo Fasiello , Sabino Matarrese , Antonio Riotto
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