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Related papers: A string scenario for inflationary cosmology

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We present a novel background-independent framework for cosmic inflation, starting with a matrix model. In this framework, inflation is portrayed as a dynamic process responsible for the generation of both space and time. This stands in…

High Energy Physics - Theory · Physics 2024-03-22 Hyun Seok Yang

An overview is presented of some cosmological aspects of string theory. Recent developments are emphasised, especially the attempts to derive inflation or alternatives to inflation from the dynamics of branes in string theory. Time…

High Energy Physics - Theory · Physics 2008-11-26 F. Quevedo

Inflationary cosmology is the leading explanation of the very early universe. Many different models of inflation have been constructed which fit current observational data. In this work theoretical and numerical methods for constraining the…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-29 Ian Huston

In previous works we have embedded the Running Vacuum Model (RVM) of Cosmology in the framework of string theory. Specifically, we considered a string-inspired Cosmology with primordial gravitational waves (GW) and gravitational anomalies,…

High Energy Physics - Theory · Physics 2021-11-22 Nick E. Mavromatos , Joan Sola

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 an inflationary scenario inspired by a recent formulation, in terms of coherent states, of non-commutative quantum field theory. We consider the semiclassical Einstein equations, and we exploit the ultraviolet finiteness of the…

General Relativity and Quantum Cosmology · Physics 2011-04-28 Massimiliano Rinaldi

The implications of string theory for understanding the dimension of decompactified spacetime are discussed. Results from a computer model designed to simulate expansion of the early universe during the string dominated phase are presented.…

High Energy Physics - Theory · Physics 2009-09-25 Gerald B. Cleaver

We discuss the large-scale structure of the universe in inflationary cosmology and the implications that it may have for the long-term future of civilizations. Although each civilization is doomed to perish, it may be possible to transmit…

Astrophysics · Physics 2011-04-20 J. Garriga , V. F. Mukhanov , K. D. Olum , A. Vilenkin

We consider a cosmological scenario within the KKLT framework for moduli stabilization in string theory. The universal open string tachyon of decaying non-BPS D-brane configurations is proposed to drive eternal topological inflation.…

High Energy Physics - Theory · Physics 2009-11-11 Daniel Cremades , Fernando Quevedo , Aninda Sinha

We consider cosmological consequences of string theory tachyon condensation. We show that it is very difficult to obtain inflation in the simplest versions of this theory. Typically, inflation in these theories could occur only at…

High Energy Physics - Theory · Physics 2009-11-07 Lev Kofman , Andrei Linde

We find a rather unique extension of inflationary scenario which avoids selfreproduction and thus resolves the problems of multiverse, predictability and initial conditions. In this theory the amplitude of the cosmological perturbations is…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 Viatcheslav Mukhanov

The inflationary scenario for the brane world driven by the bulk inflaton is proposed. The quantum fluctuations of the inflaton is calculated and compared to those of the conventional 4-dimensional inflationary scenario. It is shown that…

High Energy Physics - Theory · Physics 2009-10-31 Shinpei Kobayashi , Kazuya Koyama , Jiro Soda

In a recent paper we showed how Starobinsky-like inflation could emerge from dilaton dynamics in brane cosmology scenarios based on string theory, in which our universe is represented as a three-brane and the effective potential acquires a…

High Energy Physics - Theory · Physics 2015-06-19 John Ellis , Nick E. Mavromatos , Dimitri V. Nanopoulos

A generic feature of the known string inflationary models is that the same physics that makes the inflaton lighter than the Hubble scale during inflation often also makes other scalars this light. These scalars can acquire isocurvature…

High Energy Physics - Theory · Physics 2015-06-04 M. Cicoli , G. Tasinato , I. Zavala , C. P. Burgess , F. Quevedo

We study the implications of the stringy space-time uncertainty relation (STUR) for inflationary cosmology. By demanding that no fluctuation modes that exit the Hubble radius are affected by the nonlocality resulting from the STUR, we find…

High Energy Physics - Theory · Physics 2024-01-09 Robert Brandenberger , Pei-Ming Ho , Hikaru Kawai , Wei-Hsiang Shao

The string $\alpha^\prime$-correction to the usual Einstein action comprises a Gauss-Bonnet integrand multiplied by non-trivial functions of the modulus field $\chi$ and/or the dilaton field $\phi$. We discuss how the presence of such terms…

High Energy Physics - Theory · Physics 2007-05-23 Ishwaree P Neupane

In the non-critical string framework that we have proposed recently, the time $t$ is identified with a dynamical local renormalization group scale, the Liouville mode, and behaves as a statistical evolution parameter, flowing irreversibly…

High Energy Physics - Theory · Physics 2007-05-23 J. Ellis , N. Mavromatos , D. Nanopoulos

We embed natural inflation in an explict string theory model and derive observables in cosmology. We achieve this by compactifying the type IIB string on a Calabi-Yau orientifold, stabilizing moduli via the Large Volume Scenario, and…

High Energy Physics - Theory · Physics 2021-11-17 Stephen Angus , Kang-Sin Choi , Chang Sub Shin

We propose a method to extract predictions from quantum cosmology for inflation that can be confronted with observations. Employing the tunneling boundary condition in quantum geometrodynamics, we derive a probability distribution for the…

General Relativity and Quantum Cosmology · Physics 2015-07-21 Gianluca Calcagni , Claus Kiefer , Christian F. Steinwachs

String Gas Cosmology is a model of the evolution of the very early universe based on fundamental principles and key new degrees of freedom of string theory which are different from those of point particle field theories. In String Gas…

High Energy Physics - Theory · Physics 2015-05-28 Robert H. Brandenberger