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Related papers: String Cosmology: Concepts and Consequences

200 papers

We review the status of String Gas Cosmology after the 2015 Planck data release. String gas cosmology predicts an almost scale-invariant spectrum of cosmological perturbations with a slight red tilt, like the simplest inflationary models.…

High Energy Physics - Theory · Physics 2015-11-18 Robert H. Brandenberger

A general family of charge-current carrying cosmic string models is investigated. In the special case of circular configurations in arbitrary axially symmetric gravitational and electromagnetic backgrounds the dynamics is determined by…

High Energy Physics - Theory · Physics 2010-04-06 Arne L. Larsen

The aim of these lecture notes is to familiarize graduate students and beginning postgraduates with the basic ideas of linear cosmological perturbation theory and of structure formation scenarios. We present both the Newtonian and the…

Astrophysics · Physics 2010-12-09 Christos G. Tsagas

String theories with two dimensional space-time target spaces are characterized by the existence of a ``ground ring'' of operators of spin $(0,0)$. By understanding this ring, one can understand the symmetries of the theory and illuminate…

High Energy Physics - Theory · Physics 2010-04-07 Edward Witten

Using the formalism developed in a previous paper we analyze the cosmological implications of our conclusions concerning the scaling behaviour of a network of cosmic strings, in particular the idea that once gravitational back-reaction…

High Energy Physics - Phenomenology · Physics 2010-01-06 Daren Austin , E. J. Copeland , T. W. B. Kibble

${\rm B - L}$ cosmic strings form in a wide class of theories beyond the Standard Model which contain a ${\rm U}(1)_{{\rm B - L}}$ gauge symmetry. They can form at the end of hybrid inflation and explain, together with inflation, the Cosmic…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Jeannerot

In this review, a number of approaches to superstring cosmology which make use of key features which distinguish string theory from point particle theories are discussed, with particular emphasis on emergent scenarios. One motivation for…

High Energy Physics - Theory · Physics 2023-10-31 Robert Brandenberger

This article, written for Scolarpedia, provides a brief introduction into the subject of cosmic strings, together with a review of their main properties, cosmological evolution and observational signatures.

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Tanmay Vachaspati , Levon Pogosian , Daniele Steer

A model for particles based on preons in chiral, vector and tensor/graviton supermultiplets of unbroken global supersymmetry is engineered. The framework of the model is little string theory. Phenomenological predictions are discussed.

High Energy Physics - Phenomenology · Physics 2024-08-05 Risto Raitio

We show that the $c=1$ bosonic string theory at finite temperature has two matrix-model realizations related by a kind of duality transformation. The first realization is the standard one given by the compactified matrix quantum mechanics…

High Energy Physics - Theory · Physics 2010-04-05 Sergei Yu. Alexandrov , Vladimir A. Kazakov , Ivan K. Kostov

We discuss the continuum field theory limit of the physical scenario described in Ref. [1], the universe arising from the interpretation of the most general collection of logical codes in terms of distributions of units of energy along…

General Physics · Physics 2012-06-18 Andrea Gregori

In string theory, the traditional picture of a Universe that emerges from the inflation of a very small and highly curved space-time patch is a possibility, not a necessity: quite different initial conditions are possible, and not…

High Energy Physics - Theory · Physics 2017-06-01 M. Gasperini , G. Veneziano

Low energy string theory predicts the existence of an axion field which can lead to cosmic birefringence. We solve the electromagnetic wave equations in the presence of such an axion and a dilaton field in order to determine their effect on…

High Energy Physics - Phenomenology · Physics 2009-10-31 Prasanta Das , Pankaj Jain , Sudipta Mukherji

We calculate the lowest-order non-linear contributions to the power spectrum, two-point correlation function, and smoothed variance of the density field, for Gaussian initial conditions and scale-free initial power spectra, $P(k) \sim k^n$.…

Astrophysics · Physics 2009-10-28 Roman Scoccimarro , Josh Frieman

We review our work on the minimal length uncertainty relation as suggested by perturbative string theory. We discuss simple phenomenological implications of the minimal length uncertainty relation and then argue that the combination of the…

High Energy Physics - Theory · Physics 2011-11-01 Lay Nam Chang , Zachary Lewis , Djordje Minic , Tatsu Takeuchi

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

Topological defects, in particular cosmic strings, give rise to an interesting mechanism for generating the primordial perturbations in the early Universe which are required to explain the present structure. An overview of the cosmic string…

Astrophysics · Physics 2016-01-27 Robert H. Brandenberger

It is shown that the minimal left-right symmetric model admits cosmic string and domain wall solutions. The cosmic strings arise when the SU(2)_R is broken and can either be destabilized at the electroweak scale or remain stable through the…

High Energy Physics - Phenomenology · Physics 2014-11-17 U. A. Yajnik , Hatem Widyan , Shobhit Mahajan , Amitabha Mukherjee , Debajyoti Choudhari

String theory is the leading candidate for a unified theory of the standard model and gravity. In the last few years theorists have realized that there is a unique structure underlying string theory. In this unification a prominent role is…

High Energy Physics - Phenomenology · Physics 2007-05-23 L. E. Ibanez

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