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Related papers: Anomalous Dimensions and Non-Gaussianity

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We revisit the squeezed-limit non-Gaussianity in the single-field non-attractor inflation models from the viewpoint of the cosmological soft theorem. In the single-field attractor models, inflaton's trajectories with different initial…

High Energy Physics - Theory · Physics 2023-12-06 Teruaki Suyama , Yuichiro Tada , Masahide Yamaguchi

The presence of multiple fields during inflation might seed a detectable amount of non-Gaussianity in the curvature perturbations, which in turn becomes observable in present data sets like the cosmic microwave background (CMB) or the large…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-27 Sebastian Dorn , Erandy Ramirez , Kerstin E. Kunze , Stefan Hofmann , Torsten A. Enßlin

We study the generation of local non-Gaussianity in models of canonical single field inflation when their backgrounds are either attractor or non-attractor. We show that the invariance of inflation under space-time diffeomorphisms can be…

High Energy Physics - Theory · Physics 2023-04-13 Rafael Bravo , Gonzalo A. Palma

One of the fundamental objectives of contemporary cosmology is to understand the physics of the inflationary universe, owing to its observably verifiable predictions about the very early universe with an energy scale of $\sim 10^{16}$ GeV.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Aayush Randeep , Rajib Saha

In this paper we wish to point out the possibility of using a complex scalar field in a constant roll inflationary model, as needed for observational viability. We extend the idea of real field inflaton with constant rate of roll to a…

General Relativity and Quantum Cosmology · Physics 2023-07-04 Ali Mohammadi , Nahid Ahmadi , Mehdi Shokri

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

Galileon fields arise naturally from the decoupling limit of massive gravities, and possess special self-interactions which are protected by a spacetime generalization of Galilean symmetry. We briefly revisit the inflationary phenomenology…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-25 Raquel H. Ribeiro , David Seery

The simplicity of the CMB data, so well described by single-field inflation, raises the question whether there might be an equally simple multi-field realization consistent with the observations. We explore the idea that an approximate…

High Energy Physics - Theory · Physics 2019-07-04 Ana Achucarro , Yvette Welling

We study the evolution of various measures of quantumness of the curvature perturbation by integrating out the inaccessible entropic fluctuations in the multi-field models of inflation. In particular, we discuss the following measures of…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-17 Rathul Nath Raveendran , Sumanta Chakraborty

We use conformal symmetry to constrain the shape of inflationary correlators in the presence of long-lived vector field perturbations. Applying conformal Ward identities, we derive general expressions, up to amplitudes and normalization…

General Relativity and Quantum Cosmology · Physics 2019-09-24 Juan P. Beltrán Almeida , Josué Motoa-Manzano , César A. Valenzuela-Toledo

We propose an inflationary scenario, M-flation, in which inflation is driven by three $N\times N$ hermitian matrices $\Phi_i, i=1,2,3$. The inflation potential of our model, which is strongly motivated from string theory, is constructed…

High Energy Physics - Theory · Physics 2010-10-13 Amjad Ashoorioon , Hassan Firouzjahi , M. M. Sheikh-Jabbari

Here we concisely review the nonminimal coupling dynamics of a single scalar field in the context of purely affine gravity and extend the study to multifield dynamics. The coupling is performed via an affine connection and its associated…

General Relativity and Quantum Cosmology · Physics 2018-06-01 Hemza Azri

We investigate the possibility of constraining parameters of Effective Field Theory (EFT) of inflation with upcoming Large Scale Structure (LSS) surveys in order to have a better understanding of inflationary dynamics. With the development…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-23 Abhishek Naskar , Sayantan Choudhury , Argha Banerjee , Supratik Pal

Many controlled realizations of chaotic inflation employ pseudo-scalar axions. Pseudo-scalars \phi are naturally coupled to gauge fields through c \phi F \tilde{F}. In the presence of this coupling, gauge field quanta are copiously produced…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Neil Barnaby , Ryo Namba , Marco Peloso

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

A simple realization of inflation consists of adding the following operators to the Einstein-Hilbert action: (partial phi)^2, lambda phi^4, and xi phi^2 R, with xi a large non-minimal coupling. Recently there has been much discussion as to…

High Energy Physics - Phenomenology · Physics 2010-12-01 Mark P. Hertzberg

Motivated by the recent `Higgs-inflation' scenario based on a single inflaton field, we consider more generic two-field inflation with non-minimal coupling term. The generic analytic expressions are derived for cosmological observables with…

High Energy Physics - Phenomenology · Physics 2015-03-13 Jinsu Kim , Yoonbai Kim , Seong Chan Park

We develop a numerical statistical method to study linear cosmological fluctuations in inflationary scenarios with multiple fields, and apply it to an ensemble of six-field inflection point models in string theory. The latter are concrete…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-05 Sébastien Renaux-Petel

We study the multifield inflationary models where the cosmological perturbation is sourced by light scalar fields other than the inflaton. The corresponding perturbations are both scale invariant and special conformally invariant. We…

High Energy Physics - Theory · Physics 2015-06-05 A. Kehagias , A. Riotto

We present two examples of non-trivial field theories which are scale invariant, but not conformally invariant. This is done by placing certain field theories, which are conformally invariant in flat space, onto curved backgrounds of a…

High Energy Physics - Theory · Physics 2009-10-31 Adel M. Awad , Clifford V. Johnson