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Progress on string theory in curved spacetimes since 1992 are reviewed. After a short introduction on strings in Minkowski and curved spacetimes, we focus on strings in cosmological spacetimes. The classical behaviour of strings in FRW and…

High Energy Physics - Theory · Physics 2009-09-25 H. J. de Vega , N. Sánchez

Recent progress on string theory in curved spacetimes is reviewed. The string dynamics in cosmological and black hole spacetimes is investigated.The methods to solve the string equations of motion in curved spacetimes are described.That is,…

High Energy Physics - Theory · Physics 2007-05-23 H. J. de Vega , N. sánchez

We compute the string energy-momentum tensor and {\bf derive} the string equation of state from exact string dynamics in cosmological spacetimes. $1+1,~2+1$ and $D$-dimensional universes are treated for any expansion factor $R$. Strings…

High Energy Physics - Theory · Physics 2009-10-28 H. J. de Vega , N. Sánchez

At its very beginning, the universe is believed to have grown exponentially in size via the mechanism of inflation. The almost scale-invariant density perturbation spectrum predicted by inflation is strongly supported by cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 David F. Chernoff , S. -H. Henry Tye

We review various aspects of de Sitter spacetime in string theory: its status as an effective field theory spacetime solution, its relation to the vacuum energy problem in string theory, its (global) holographic definition in terms of two…

High Energy Physics - Theory · Physics 2023-08-30 Per Berglund , Tristan Hübsch , Djordje Minic

In this paper we consider an inflating universe with long straight cosmic string along z-axis. We show that the effect of cosmic string can be taken as a perturbation on the background of FRW metric. Then by doing cosmological perturbations…

General Relativity and Quantum Cosmology · Physics 2024-05-07 S. Azar Ag Galeh , A. M. Abbassi , M. H. Abbassi

This thesis is dedicated to the study of inflationary scenarios based on string theory. Inflation is a brief period of accelerated expansion in the very early Universe which gives natural explanations for problems of the Standard Big Bang…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-15 Larissa C. Lorenz

If string theory controls physics at the string scale, the dynamics of the early universe before the GUT era will be governed by the low-energy string equations of motion. Studying these equations for FRW spacetimes, we find that depending…

High Energy Physics - Theory · Physics 2008-12-18 Dalia S. Goldwirth , Malcolm J. Perry

Inflation of cosmic gauge and global strings is investigated by numerically solving the combined Einstein and field equations. Above some critical symmetry-breaking scales, the strings undergo inflation along the radial direction as well as…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Inyong Cho

It was shown by Garriga and Vilenkin that the circular shape of nucleated cosmic strings, of zero loop-energy in de Sitter space, is stable in the sense that the ratio of the mean fluctuation amplitude to the loop radius is constant. This…

High Energy Physics - Theory · Physics 2009-10-28 A. L. Larsen

Brane inflation is a specific realization of the inflationary universe scenario in the early universe within the brane world framework in string theory. The naturalness and robustness of this realistic scenario is explained. Its predictions…

High Energy Physics - Theory · Physics 2008-11-26 S. -H. Henry Tye

This paper explores the phenomenon of particle creation associated with cosmic strings in de Sitter spacetime, a model that represents the universe exponential expansion. We examine how the presence of cosmic strings in a de Sitter…

General Relativity and Quantum Cosmology · Physics 2025-06-10 Bilgehan Baris Oner , Ozlem Yesiltas

Attempts to connect string theory with astrophysical observation are hampered by a jargon barrier, where an intimidating profusion of orientifolds, Kahler potentials, etc. dissuades cosmologists from attempting to work out the astrophysical…

Astrophysics · Physics 2008-11-26 Mark P. Hertzberg , Max Tegmark , Shamit Kachru , Jessie Shelton , Onur Ozcan

The cosmic string theory for cosmological fluctuations is a good example of healthy scientific progress in cosmology. It is a well defined physically motivated model that has been tested by cosmological observations and has been ruled out…

Astrophysics · Physics 2009-11-10 L. Perivolaropoulos

This is a short review of string cosmology. We wish to connect string-scale physics as closely as possible to observables accessible to current or near-future experiments. Our possible best hope to do so is a description of inflation in…

High Energy Physics - Theory · Physics 2015-12-07 Alexander Westphal

Cosmic strings provide a radically different paradigm for the formation of structure to the prevailing inflationary one. They afford some extra technical complications: for example, the calculation of the power spectrum of matter and…

Astrophysics · Physics 2007-05-23 Mark Hindmarsh , Mairi Sakellariadou , Graham R. Vincent

We review applications of string theory to cosmology, from primordial times to the present-day accelerated expansion. Starting with a brief overview of cosmology and string compactifications, we discuss in detail moduli stabilisation,…

High Energy Physics - Theory · Physics 2023-05-08 Michele Cicoli , Joseph P. Conlon , Anshuman Maharana , Susha Parameswaran , Fernando Quevedo , Ivonne Zavala

In the first part of this talk, I consider some exact string solutions in curved spacetimes. In curved spacetimes with a Killing vector (timelike or spacelike), the string equations of motion and constraints are reduced to the Hamilton…

High Energy Physics - Theory · Physics 2007-05-23 A. L. Larsen

We investigate some classical aspects of fundamental strings via numerical experiments. In particular, we study the thermodynamics of a string network within a toroidal universe, as a function of string energy density and space…

High Energy Physics - Theory · Physics 2009-10-28 Mairi Sakellariadou

A synthetic report of the advances in the study of classical and quantum string dynamics in curved backgrounds is provided, namely: the new feature of multistring solutions; the effect of a cosmological constant and of spacial curvature on…

High Energy Physics - Theory · Physics 2011-07-19 Norma G. Sanchez
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