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.