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Related papers: Hamilton-Jacobi Formalism for Tachyon Inflation

200 papers

We study inflation in the Brans-Dicke gravity as a special model of the scalar-tensor gravity. We obtain the inflationary observables containing the scalar spectral index, the tensor-to-scalar ratio, the running of the scalar spectral index…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-06 B. Tahmasebzadeh , K. Rezazadeh , K. Karami

We argue that the non-detection of primordial tensor modes has taught us a great deal about the primordial universe. In single-field slow-roll inflation, the current upper bound on the tensor-to-scalar ratio, $r < 0.07$ $(95 \% ~CL)$,…

High Energy Physics - Theory · Physics 2017-06-21 Enrico Pajer , Guilherme L. Pimentel , Jaap V. S. Van Wijck

We study the warm-tachyon inflationary universe model with viscous pressure in high-dissipation regime. General conditions which are required for this model to be realizable are derived in the slow-roll approximation. We present analytic…

General Relativity and Quantum Cosmology · Physics 2015-06-22 M. R. Setare , V. Kamali

We study analytically and numerically the inflationary solutions for various type scalar potentials in the nonminimally coupled scalar field theory. The Hamilton-Jacobi equation is used to deal with nonlinear evolutions of inhomogeneous…

Astrophysics · Physics 2009-11-11 Seoktae Koh , Sang Pyo Kim , Doo Jong Song

In this study, we provide an alternatively reformulated interpretation of Gibbons-Hawking radiation as well as inflation. By using a spacetime quantization procedure, proposed recently by L.C. C\'eleri et al., in anti-de Sitter space we…

General Relativity and Quantum Cosmology · Physics 2020-05-08 Naouel Boulkaboul

We extend the geometric Hamilton-Jacobi formalism for hamiltonian mechanics to higher order field theories with regular lagrangian density. We also investigate the dependence of the formalism on the lagrangian density in the class of those…

Differential Geometry · Mathematics 2011-02-01 L. Vitagliano

Single-field inflaton models in the kinetic dominance period admit formal solutions given by generalized asymptotic expansions called psi series. We present a method for computing psi series for the Hubble parameter as a function of the…

General Relativity and Quantum Cosmology · Physics 2024-12-18 Elena Medina , Luis Martínez Alonso

We investigate the cosmological inflation in a class of supergravity models that are generalizations of non-supersymmetric $R^2$ models. Although such models have been extensively studied recently, especially after the launch of the PLANCK…

High Energy Physics - Theory · Physics 2015-06-23 G. A. Diamandis , B. C. Georgalas , K. Kaskavelis , P. Kouroumalou , A. B. Lahanas , G. Pavlopoulos

Decoupling of heavy modes in effective low energy theory is one of the most fundamental concepts in physics. It tells us that modes must have a negligible effect on the physics of gravitational backgrounds with curvature radius larger than…

High Energy Physics - Theory · Physics 2020-05-12 Gia Dvali , Alex Kehagias , Antonio Riotto

In this work we discuss the application of the Hamilton-Jacobi formalism on the scalar field implementation of Generalized Chaplygin Gas models. This corresponds to a Generalised Born-Infeld action for the scalar field, which in an initial…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-20 Yordan Ignatov , Mauro Pieroni

The latest released data from Planck in 2018, put up tighter constraints on inflationary parameters. In the present article, the in-built symmetry of the non-minimally coupled scalar-tensor theory of gravity is used to fix the coupling…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-16 Dalia Saha , Susmita Sanyal , Abhik Kumar Sanyal

The inflationary cosmology paradigm is very successful in explaining the CMB anisotropy to the percent level. Besides the dependence on the inflationary model, the power spectra, spectral tilt and non-Gaussianity of the CMB temperature…

High Energy Physics - Theory · Physics 2014-02-18 Amjad Ashoorioon , Konstantinos Dimopoulos , M. M. Sheikh-Jabbari , Gary Shiu

The classical and relativistic Hamilton-Jacobi approach is applied to the one-dimensional homogeneous potential, $V(q)=\alpha q^n$, where $\alpha$ and $n$ are continuously varying parameters. In the non-relativistic case, the exact…

General Relativity and Quantum Cosmology · Physics 2015-06-25 R. C. Santos , J. Santos , J. A. S. Lima

In this paper we will analyze generic predictions of an inflection-point model of inflation with Hubble-induced corrections and study them in light of the Planck data. Typically inflection-point models of inflation can be embedded within…

High Energy Physics - Phenomenology · Physics 2013-07-29 Sayantan Choudhury , Anupam Mazumdar , Supratik Pal

Current bounds on the tensor-to-scalar ratio imply that the energy scale of inflation may lie below the grand-unified scale. In this paper, we show that in a broad class of single-field inflation models with sufficiently small energy…

High Energy Physics - Phenomenology · Physics 2026-02-18 Haruto Masubuchi , Yuma Narita , Wen Yin

Using the Hubble parameter as new `inverse time' coordinate ($H$-formalism), a new method of reconstructing the inflaton potential is developed also using older results which, in principle, is applicable to any order of the slow-roll…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Eckehard W. Mielke , Franz E. Schunck

In holographic inflation, the $4D$ cosmological dynamics is postulated to be dual to the renormalization group flow of a $3D$ Euclidean conformal field theory with marginally relevant operators. The scalar potential of the $4D$ theory ---in…

High Energy Physics - Theory · Physics 2019-05-22 Ana Achucarro , Sebastian Cespedes , Anne-Christine Davis , Gonzalo A. Palma

We investigate an ability of the exponential power-law inflation to be phenomenologically correct model of the early universe. GR scalar cosmology equations we study in Ivanov-Salopek-Bond (or Hamilton-Jacobi like) representation where the…

General Relativity and Quantum Cosmology · Physics 2025-01-22 I. V. Fomin , S. V. Chervon

We present the first quantum field theory model of inflation that is renormalizable in the matter sector, with a super-Hubble inflaton mass and sub-Planckian field excursions, which is thus technically natural and consistent with a…

High Energy Physics - Phenomenology · Physics 2021-01-11 Mar Bastero-Gil , Arjun Berera , Rudnei O. Ramos , João G. Rosa

Recently, it was proposed that a small true vacuum universe can inflate spontaneously, in principle. Furthermore, there should be matter creation in vacuum inflation due to quantum fluctuations, and the matter created will influence the…

General Relativity and Quantum Cosmology · Physics 2017-05-01 Zhiqiang Huang , Dongfeng Gao , Qing-yu Cai