José P. P. Vieira
FCUP

Abstract
In this talk I will summarize the work I've done in the context of grant CAUP-03/2011-BII. In recent years, the issue of whether fundamental dimensionless couplings such as the fine-structure constant (α) vary has been keeping particle physicists and cosmologists on the edge of their seats. The efforts to address this problem have resulted in an array of theoretical models which depend on certain unification parameters (R and S) whose bounds are yet unclear. By means of assessing the impact a specific variation of α must have in the structure of a polytropic star in the light of any such model, through computational methods, it is possible to establish bounds on the variations of these couplings and impose constraints on the possible values of R and S.
The aim of this talk shall be to first provide the audience with the gist of the theory involved in those methods and then present some examples of results which can be obtained in this way, briefly commenting on how they can be used in actual experiments seeking to determine either R, S or a variation range for α in a region of the Universe where stars similar to our own Sun can be found.

24 October 2011, 13:30

Centro de Astrofísica
Rua das Estrelas
4150-762 Porto