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We compute corrections to the inflationary potential due to conformally coupled non-relativistic matter. We find that under certain conditions of the matter coupling, inflation may be interrupted abruptly. We display this in the…

General Relativity and Quantum Cosmology · Physics 2015-11-11 Sebastian Cespedes , Anne-Christine Davis

We investigate the pre-inflationary dynamics of inflation with the Starobinsky potential, favored by recent data from the Planck mission, using techniques developed to study cosmological perturbations on quantum spacetimes in the framework…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Béatrice Bonga , Brajesh Gupt

The magnitude of B-mode polarization in the cosmic microwave background as measured by BICEP2 favours models of chaotic inflation with a quadratic $m^2 \phi^2/2$ potential, whereas data from the Planck satellite favour a small value of the…

High Energy Physics - Phenomenology · Physics 2014-08-25 John Ellis , Marcos A. G. Garcia , Dimitri V. Nanopoulos , Keith A. Olive

We study inflationary constraints from reheating on two classes of single-field inflationary models: a generalized $\alpha$-attractor with potential $V(\phi) = V_0 \!\left(1 - \sech^p\!\left[\phi/(\sqrt{6\alpha}\,M_{Pl})\right]\right)$ and…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 Gabriel German , Juan Carlos Hidalgo

In this work, we investigate the non-minimally coupled scenario in the context of warm inflation with quantum-corrected self-interacting potential. We transform the potential in the Jordan frame to the Einstein frame and consider a…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-06 Daris Samart , Patinya Ma-adlerd , Peeravit Koad , Phongpichit Channuie

Single field inflationary models are investigated within Palatini quadratic gravity represented by $R+\alpha R^2$ along with a non-minimal coupling of the form $f(\phi) R$ between the inflaton field $\phi$ and the gravity. The treatment is…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Mahmoud AlHallak

We derive new constraints on the Hubble function H(phi) and subsequently on the inflationary potential V(phi) from WMAP 3-year data combined with the Sloan Luminous Red Galaxy survey (SDSS-LRG), using a new methodology which appears to be…

Astrophysics · Physics 2009-06-23 Julien Lesgourgues , Alexei A. Starobinsky , Wessel Valkenburg

Building on the success of the Starobinsky model in describing the inflationary period of the universe, we investigate two simple generalizations of this model and their constraints imposed by the reheating epoch. The first generalization…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-21 Marcos A. G. Garcia , Gabriel Germán , R. Gonzalez Quaglia , A. M. Moran Colorado

An inflationary model in the framework of noncommutative space-time may generate a nontrivial running of the scalar spectral index, but usually induces a large tensor-to-scalar ratio simultaneously. With the latest observational data from…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-11 Nan Li , Xin Zhang

We investigate the observational constraints on $\alpha$-attractor inflationary models and their post-inflationary reheating dynamics in light of the latest CMB data from ACT DR6 combined with Planck18, BICEP/$Keck$ 2018, and DESI…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-06 Md Riajul Haque , Sourav Pal , Debarun Paul

We study the inflationary scenario in the Tsallis entropy-based cosmology. The Friedmann equations in this setup can be derived by using the first law of thermodynamics. To derive the relations of the power spectra of the scalar and tensor…

General Relativity and Quantum Cosmology · Physics 2024-01-26 Zeinab Teimoori , Kazem Rezazadeh , Abasat Rostami

Inspired by the reconstruction scheme of the inflaton field potential $V(\phi)$ from the attractors$n_s(N)$, we investigate the viability of reconstruct the inflationary potential within the framework of k-inflation for a non-linear kinetic…

General Relativity and Quantum Cosmology · Physics 2023-05-10 Ramon Herrera , Michel Housset , Constanza Osses , Nelson Videla

We study a model of inflation based on $\mathcal{N}=1$ supergravity essentially depending on one effective parameter. Under a field transformation we show that this model turns out to be equivalent to a previously studied supergravity model…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-13 Gabriel Germán , Juan Carlos Hidalgo , Francisco X. Linares Cedeño , Ariadna Montiel , J. Alberto Vázquez

Analyses of inflation models are usually conducted assuming a specific range---e.g., $N_k \simeq 50-60$--of the number $N_k$ of $e$-folds of inflation. However, the analysis can also be performed by taking into account constraints imposed…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Lingyuan Ji , Marc Kamionkowski

We develop a consistent analytic approach to determine the conditions under which slow roll inflation can arise when the inflaton is the same scalar field that is responsible for the bounce in Loop Quantum Cosmology (LQC). We find that the…

General Relativity and Quantum Cosmology · Physics 2019-11-04 Anshuman Bhardwaj , Edmund J. Copeland , Jorma Louko

In this paper we develop the formalism for the stochastic approach to inflation at all order in slow-roll parameters. This is done by including the momentum and Hamiltonian constraints into the stochastic equations. We then specialise to…

General Relativity and Quantum Cosmology · Physics 2022-02-09 Diego Cruces , Cristiano Germani

We consider a non-canonic field in the context of Starobinsky inflation. We work in Einstein-frame. In this frame, the gravitational part of the action is equivalent to the Hilbert-Einstein action, plus a scalar field called scalaron. We…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Salomeh Khoeini-Moghaddam

We investigate inflation in modified gravity framework by introducing a direct coupling term between a scalar field $\phi$ and the trace of the energy momentum tensor $T$ as $f(\phi,T) = 2 \phi( \kappa^{1/2} \alpha T + \kappa^{5/2} \beta…

General Relativity and Quantum Cosmology · Physics 2022-10-17 Ashmita , Payel Sarkar , Prasanta Kumar Das

The ACT data shows an enhancement in the value of the scalar spectral index, as $n_s = 0.9743 \pm 0.0034$, leading to disfavoring many inflationary models, including the Starobinsky model. To satisfy the constraint made by ACT, we will…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-09 Yogesh , Abolhassan Mohammadi , Qiang Wu , Tao Zhu

The Starobinsky model of inflation remains consistent with observation, forty years after its introduction. It provides a well motivated origin for the scalar inflaton, the "scaleron" with a mass of $O(10^{13})$ GeV, emerging as a graviton…

High Energy Physics - Theory · Physics 2021-07-07 Christopher T. Hill , Graham G. Ross