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We show that it is possible to simulate realistic inhomogeneities during cosmological inflation with high precision using {Numerical Relativity}. Stochastic initial conditions are set in line with the Bunch-Davies {vacuum} and satisfy the…

General Relativity and Quantum Cosmology · Physics 2025-07-24 Yoann L. Launay , Gerasimos I. Rigopoulos , E. Paul S. Shellard

We generalize the consistency condition for the three-point function in single field inflation to the case of dissipative, multi-field, single-clock models. We use the recently introduced extension of the effective field theory of inflation…

High Energy Physics - Theory · Physics 2015-06-05 Diana Lopez Nacir , Rafael A. Porto , Matias Zaldarriaga

We study the effects of non-trivial initial quantum states for inflationary fluctuations within the context of the effective field theory for inflation constructed by Cheung et al. which allows us to discriminate between different initial…

High Energy Physics - Theory · Physics 2013-11-20 Nishant Agarwal , R. Holman , Andrew J. Tolley , Jennifer Lin

We show that a perturbed inflationary spacetime, driven by a canonical single scalar field, is invariant under a special class of coordinate transformations together with a field reparametrization of the curvature perturbation in co-moving…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-15 Rafael Bravo , Sander Mooij , Gonzalo A. Palma , Bastián Pradenas

The Ward identities for conformal symmetries in single field models of inflation are studied in more detail in momentum space. For a class of generalized single field models, where the inflaton action contains arbitrary powers of the scalar…

High Energy Physics - Theory · Physics 2016-12-28 Ashish Shukla , Sandip P. Trivedi , V. Vishal

We compute the non-Gaussianities that arise in single field, slow roll inflationary models arising from arbitrary homogeneous initial states, as well as subleading contributions to the power spectrum. Non Bunch-Davies vacuum initial states…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-12 Sina Bahrami , Éanna É. Flanagan

We derive consistency relations for correlators of scalar cosmological perturbations which hold in the "squeezed limit" in which one or more of the external momenta become soft. Our results are formulated as relations between suitably…

High Energy Physics - Theory · Physics 2013-06-14 Walter D. Goldberger , Lam Hui , Alberto Nicolis

If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Sander Mooij , Gonzalo A. Palma , Grigoris Panotopoulos , Alex Soto

We calculate the three-point correlation function evaluated at horizon crossing for a set of interacting scalar fields coupled to gravity during inflation. This provides the initial condition for the three-point function of the curvature…

Astrophysics · Physics 2008-11-26 David Seery , James E. Lidsey

We investigate the phenomenological consequences of a modification of the initial state of a single inflationary field. While single-field inflation with the standard Bunch-Davies initial vacuum state does not generally produce a measurable…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jonathan Ganc , Eiichiro Komatsu

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 compute the three point correlation functions for primordial scalar and tensor fluctuations in single field inflationary models. We obtain explicit expressions in the slow roll limit where the answer is given terms of the two usual slow…

Astrophysics · Physics 2009-11-07 Juan Maldacena

We investigate the symmetry constraints on the bispectrum, i.e. the three-point correlation function of primordial density fluctuations, in slow-roll inflation. It follows from the defining property of slow-roll inflation that primordial…

High Energy Physics - Theory · Physics 2013-03-29 Koenraad Schalm , Gary Shiu , Ted van der Aalst

Non-Gaussianities of the primordial density perturbations have emerged as a very powerful possible signal to test the dynamics that drove the period of inflation. While in general the most sensitive observable is the three-point function in…

High Energy Physics - Theory · Physics 2011-01-17 Leonardo Senatore , Matias Zaldarriaga

We compute the 3-point correlation function for a general model of inflation driven by a single, minimally coupled scalar field. Our approach is based on the numerical evaluation of both the perturbation equations and the integrals which…

Astrophysics · Physics 2010-10-27 Xingang Chen , Richard Easther , Eugene A. Lim

We use the dS/CFT correspondence and bulk gravity to predict the form of the renormalized holographic three-point correlation function of the operator which is dual to the inflaton field perturbation during single-field, slow-roll…

Astrophysics · Physics 2007-05-23 David Seery , James E. Lidsey

We identify a two-parameter family of excited states within slow-roll inflation for which either the corrections to the two-point function or the characteristic signatures of excited states in the three-point function -- i.e. the…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-28 Amjad Ashoorioon , Gary Shiu

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…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-26 Christian T. Byrnes

In this paper, we present a non-Gaussianity consistency relation that enables the calculation of the squeezed limit bispectrum of the curvature perturbation in single-field inflationary models by carefully inspecting the background…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 Mohammad Hossein Namjoo

In this paper we present a simple, toy model of single field inflation in which the standard non-Gaussianity consistency condition is violated. In this model the curvature perturbations on super-horizon scales are not conserved and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Mohammad Hossein Namjoo , Hassan Firouzjahi , Misao Sasaki