Principal Investigator
Carlos J. A. P. Martins

Abstract
Topological defects necessarily form at phase transitions in the early universe. Being non-linear objects, their study requires a combination of phenomenological analytic modeling and complex numerical simulations. Among the possible defects, superstring networks are particularly interesting, and recent work suggests their unavoidable formation at the phase transition that ends inflation.

The recent release of ESA's Planck Surveyor first year CMB temperature data places interesting constrains on the simplest phenomenological classes of these models, but we are still lacking the observational data and the underlying theoretical knowledge to allow us to test the more realistic models.

Although cosmic superstrings share many of the properties of standard strings that have been studied in the past, there are important differences: most notably they do not always intercommute when they intersect and the formation of junctions occurs naturally as a result the interaction between the string. Hybrid networks containing various types of defects can also form.

Understanding the cosmological evolution of such realistic networks is an open problem that this project will address. this has a direct impact on the observational signatures of (and searchers for) these objects. The upcoming availability of further high-precision data, both from Planck (with additional temperature an polarization data released in June 2014) and from other experiments, makes this study particularly timely.

bolseiro: José Pedro Pinto Vieira
orientador: Carlos Martins

Start
1 January 2014
End
31 March 2015

Funding Institution
Fundação Calouste Gulbenkian