astro-ph/0110285

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Abstract. Topological defects are ubiquitous in condensed-matter physics but only hypothetical in the early universe. In spite of this, even an indirect evidence for one of these cosmic objects would revolutionize our vision of the cosmos. We give here an introduction to the subject of cosmic topological defects and their possible observable signatures. Beginning with a review of the basics of general defect formation and evolution, we then focus on mainly two topics in some detail: conducting strings and vorton formation, and some specific imprints in the cosmic microwave background radiation from simulated cosmic strings.

Table of Contents

INTRODUCTION

How defects form

Phase transitions and finite temperature field theory

The Kibble mechanism

A survey of topological defects

Conditions for their existence: topological criteria

DEFECTS IN THE UNIVERSE

Local and global monopoles and domain walls

Are defects inflated away?

Cosmic strings

String loops and scaling

Global textures

Evolution of global textures

CURRENTS ALONG STRINGS

Goto--Nambu Strings

Witten strings

Superconducting strings !

Macroscopic string description

The dual formalism

The Future of the Loops

STRUCTURE FORMATION FROM DEFECTS

Cosmic strings

Textures

CMB SIGNATURES FROM DEFECTS

CMB power spectrum from strings

CMB bispectrum from active models

CMB bispectrum from strings

CMB polarization

VARIA

Astrophysical footprints

Cosmology in the Lab

Gravitational waves from strings

More cosmological miscellanea

REFERENCES

¹ Lecture Notes for the First Bolivian School on Cosmology, La Paz, 24-28 September, 2001. http://www.umsanet.edu.bo/fisica/cosmo2k1.html Back.