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Related papers: Noncommutative models in patch cosmology

200 papers

Generalizing the noncommutative harmonic oscillator construction, we propose a new extension of quantum field theory based on the concept of "noncommutative fields". Our description permits to break the usual particle-antiparticle…

High Energy Physics - Theory · Physics 2009-11-10 J. M. Carmona , J. L. Cortes , J. Gamboa , F. Mendez

Multi-field inflation can be inherently non-predictive, with the exception of models with strong attractors. In this work, we focus on models with multiple scalar fields that are non-minimally coupled to the space-time Ricci curvature…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-18 Perseas Christodoulidis , Robert Rosati , Evangelos I. Sfakianakis

In single-field, slow-roll inflationary models, scalar and tensorial (Gaussian) perturbations are both characterized by a zero mean and a non-zero variance. In position space, the corresponding variance of those fields diverges in the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 I. Agullo , J. Navarro-Salas , Gonzalo J. Olmo , Leonard Parker

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

The linear cosmological perturbation theory of almost homogeneous and isotropic perfect fluid and scalar field universes is reconsidered and formally simplified. Using the existence of a covariant conserved quantity on large perturbation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Winfried Zimdahl

Cosmological solution to the gravitational field equations in the generalized Randall-Sundrum model for an anisotropic brane with Bianchi I geometry and perfect fluid as matter sources has been considered. The matter on the brane is…

General Relativity and Quantum Cosmology · Physics 2019-12-16 Rikpratik Sengupta , Prasenjit Paul , Bikash Chandra Paul , Saibal Ray

To understand mechanisms leading to inflation and late acceleration of the Universe it is important to see how one or a set of quantum fields may evolve such that the classical energy-momentum tensor behave similar to a cosmological…

General Relativity and Quantum Cosmology · Physics 2018-07-17 Houri Ziaeepour

We derive a system of cosmological equations for a braneworld with induced curvature which is a junction between several bulk spaces. The permutation symmetry of the bulk spaces is not imposed, and the values of the fundamental constants,…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yuri Shtanov , Alexander Viznyuk , Luis Norberto Granda

We construct braneworld effective action in two brane Randall-Sundrum model and show that the radion mode plays the role of a scalar field localizing essentially nonlocal part of this action. Non-minimal curvature coupling of this field…

High Energy Physics - Theory · Physics 2009-11-07 A. O. Barvinsky

We present uniform rate inflation in a modified $f(T, \mathcal{T}) $ gravity. It is found that early inflation can be realized even with a scalar field field with a quadratic potential and a negative cosmological constant. We construct…

General Relativity and Quantum Cosmology · Physics 2025-07-02 Priyanka Mandal , B. C. Paul

We describe a broad class of multi-field inflationary models with spontaneously broken conformal invariance. It generalizes the recently discovered class of cosmological attractors with a single inflaton field. In the new multi-field…

High Energy Physics - Theory · Physics 2015-06-17 Renata Kallosh , Andrei Linde

We calculate the spectral index and tensor-to-scalar ratio for patch inflation arisen from the Gauss-Bonnet braneworld scenario. The patch cosmological models consist of Gauss-Bonnet (GB), Randall-Sundrum (RS), and 4D general relativistic…

Astrophysics · Physics 2010-04-05 Hungsoo Kim , Kyong Hee Kim , Hyung Won Lee , Yun Soo Myung

We examine some general properties of a certain class of scalar filed theory models containing non-topological soliton solutions in the context of brane world models with compact large extra dimensions. If a scalar field is allowed to…

High Energy Physics - Phenomenology · Physics 2009-11-07 Dejan Stojkovic

A particularly attractive feature of inflation is that quantum fluctuations in the inflaton field may have seeded inhomogeneities in the cosmic microwave background (CMB) and the formation of large-scale structure. In this paper, we…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-21 Fulvio Melia

We calculate the spectral index and tensor-to-scalar ratio for patch inflation defined by $H^2\approx \beta^2_q V^q$ and $\dot{\phi}\approx -V'/3H$, using the slow-roll expansion. The patch cosmology arisen from the Gauss-Bonnet braneworld…

Astrophysics · Physics 2009-11-10 Kyong Hee Kim , Yun Soo Myung

In this paper, we study a type of one-field model for open inflationary universe models in the context of the brane world models. In the scenario of a one-bubble universe model, we determine and characterize the existence of the Coleman-De…

High Energy Physics - Theory · Physics 2009-11-10 Sergio del Campo , Ramon Herrera , Joel Saavedra

We study warm-viscous inflationary universe model on the brane, in a tachyon field theory. We obtain the general conditions which are required for this model to be realizable. In longitudinal gauge, the primoradial perturbation parameters…

High Energy Physics - Theory · Physics 2015-06-12 M. R. Setare , V. Kamali

Recent developments in the theory of extra dimensions have opened up avenues to confront such theories with cosmological tests. We discuss a brane-world model with a bulk scalar field, motivated by supergravity. The low-energy effective…

Astrophysics · Physics 2009-11-10 A. -C. Davis , Ph. Brax , C. van de Bruck

We construct a model where cosmological perturbations are analytically solved based on dilatonic brane worlds. A bulk scalar field has an exponential potential in the bulk and an exponential coupling to the brane tension. The bulk scalar…

High Energy Physics - Theory · Physics 2009-11-10 Kazuya Koyama , Keitaro Takahashi

We investigate in the context of brane inflation the possibility of additional light scalar fields generating significant power spectrum and non-Gaussianities at the end of inflation affecting the CMB scale observations. We consider the…

High Energy Physics - Theory · Physics 2008-11-26 Heng-Yu Chen , Jinn-Ouk Gong , Gary Shiu