English
Related papers

Related papers: Anisotropic Inflation from Extra Dimensions

200 papers

We propose a simple modified gravity model without any initial matter fields in terms of several alternative non-Riemannian spacetime volume elements within the metric (second order) formalism. We show how the non-Riemannian…

General Relativity and Quantum Cosmology · Physics 2019-10-02 David Benisty , Eduardo Guendelman , Emil Nissimov , Svetlana Pacheva

We study the dynamics of a homogeneous, isotropic, and positively curved universe in the presence of a SU(2) gauge field or a triplet of mutually orthogonal vector fields. In the SU(2) case we use the previously known ansatz for the…

General Relativity and Quantum Cosmology · Physics 2021-10-11 Tomoaki Murata , Tsutomu Kobayashi

Non-perturbative corrections from loop quantum cosmology (LQC) to the scalar matter sector is already known to imply inflation. We prove that the LQC modified scalar field generates exponential inflation in the small scale factor regime,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ghanashyam Date , Golam Mortuza Hossain

We investigate the inflation of Universe in a model of four dimensional dilatonic gravity with a massive dilaton field $\Phi$. The dilaton plays simultaneously the roles of an inflation field and a quintessence field. It yields a sequential…

General Relativity and Quantum Cosmology · Physics 2009-11-07 P. P. Fiziev , D. A. Georgieva

This paper investigates Starobinsky's model of inflation driven by the trace anomaly of conformally coupled matter fields. This model does not suffer from the problem of contrived initial conditions that occurs in most models of inflation…

High Energy Physics - Theory · Physics 2009-10-31 S. W. Hawking , T. Hertog , H. S. Reall

The main purpose of this paper is to advance a unified theory of dark matter, dark energy, and inflation first formulated in 2008. Our minimal affine extension of the GR has geodesics coinciding with the pseudo Riemannian ones, up to…

General Relativity and Quantum Cosmology · Physics 2019-07-02 Alexandre T. Filippov

We present a simple higher dimensional FRW type of model where the acceleration is apparently caused by the presence of the extra dimensions. Assuming an ansatz in the form of the deceleration parameter we get a class of solutions some of…

General Relativity and Quantum Cosmology · Physics 2009-11-11 S. Chatterjee , A. Banerjee , Y. Z. Zhang

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical Abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ralf Hofmann , Mathias Th. Keil

Most high-energy constructions that realise a phase of cosmic inflation contain many degrees of freedom. Yet, cosmological observations are all consistent with single-field embeddings. We show how volume selection effects explain this…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-24 Koki Tokeshi , Vincent Vennin

We propose a large class of nonsingular cosmologies of arbitrary spatial curvature whose cosmic history is determined by a primeval dynamical $\Lambda (t)$-term. For all values of the curvature, the models evolve between two extreme de…

General Relativity and Quantum Cosmology · Physics 2015-06-23 J. A. S. Lima , E. L. D. Perico , G. J. M. Zilioti

Within supersymmetry we provide an example where the inflaton sector is derived from a gauge invariant polynomial of SU(N) or SO(N) gauge theory. Inflation in our model is driven by multi-flat directions, which assist accelerated expansion.…

High Energy Physics - Theory · Physics 2009-11-10 Asko Jokinen , Anupam Mazumdar

We study an inflationary scenario in supergravity model with a gauge kinetic function. We find exact anisotropic power-law inflationary solutions when both the potential function for an inflaton and the gauge kinetic function are…

High Energy Physics - Theory · Physics 2011-03-10 Sugumi Kanno , Jiro Soda , Masa-aki Watanabe

We argue that the emergent spacetime picture admits a background-independent formulation of cosmic inflation. The inflation in this picture corresponds to the dynamical emergence of spacetime while the conventional inflation is simply an…

High Energy Physics - Theory · Physics 2019-02-27 Hyun Seok Yang

We propose a cosmological model that describes isotropic expansion of inhomogeneous universe. The energy-momentum tensor that creates the spatial inhomogeneity may not affect the uniform expansion scaling factor $a(t)$ in the FLRW-like…

High Energy Physics - Theory · Physics 2014-10-15 Wei-Jian Geng , H. Lu

We suggest a structure for the vacuum comprised of a network of tightly knotted/linked flux tubes formed in a QCD-like cosmological phase transition and show that such a network can drive cosmological inflation. As the network can be…

High Energy Physics - Phenomenology · Physics 2015-08-07 Arjun Berera , Roman V. Buniy , Thomas W. Kephart , Heinrich Päs , João G. Rosa

A semiclassical gravitation model is outlined which makes use of the Casimir energy density of vacuum fluctuations in extra compactified dimensions to produce the present-day cosmological constant as rho_LAMBDA ~ M^8/M_P^4, where M_P is the…

High Energy Physics - Theory · Physics 2014-11-18 Carl L. Gardner

Cosmological inflation is studied in the case where the inflaton is the overall modulus $T$ for an orbifold. General forms of the (non-perturbative) superpotential are considered to ensure that $G=K+{\rm ln}|W|^2$ is modular invariant. We…

High Energy Physics - Theory · Physics 2009-10-31 D. Bailin , G. V. Kraniotis , A. Love

A model of cosmological inflation is proposed in which field space is a hyperbolic plane. The inflaton never slow-rolls, and instead orbits the bottom of the potential, buoyed by a centrifugal force. Though initial velocities redshift away…

High Energy Physics - Theory · Physics 2019-01-03 Adam R. Brown

We investigate the evolution of cosmological anisotropies within the framework of $f\left(G\right)$-gravity. Specifically, we consider a locally rotationally symmetric geometry in four-dimensional spacetime that describes the Bianchi I,…

General Relativity and Quantum Cosmology · Physics 2025-12-25 R. Bogadi , A. Giacomini , M. Govender , C. Hansraj , G. Leon , A. Paliathanasis

We consider several new classes of viable vector field alternatives to the inflaton and quintessence scalar fields. Spatial vector fields are shown to be compatible with the cosmological anisotropy bounds if only slightly displaced from the…

Astrophysics · Physics 2010-11-19 Tomi S. Koivisto , David F. Mota