04/12/2017 - 15:30
Dr. Diego Sáez Gómez del Instituto de Ciencias del Espacio (ICE-CSIC/IEEC) de Barcelona
Is the universe heading toward a violent end?
As pointed by the observations, the Universe expansion is increasing its speed. Nevertheless, how this acceleration works is still a mystery that has been called dark energy. On the other hand, General Relativity contains inherently singularities, which refer to singular points of the spacetime, i.e. geodesically incomplete spacetimes according to the usual definitions by Hawking and Ellis. Over the last years, some proposed dark energy models drive the universe towards one of these future "singularities", near which the laws of physics lose their validity.
In this talk, I will review and show the physical features of these singularities and present a new one that encompasses all the future singularities. Then, I will present several phenomenological parameterizations of the Hubble expansion rate to model different types of singularities and use SN Ia, BAO and H(z) data to constrain how far in the future the singularity may be, and how good the models are in comparison with the concordance model in cosmology.
Miércoles 12 de Abril 2017
Sala de Conferencias, 3er Piso
Departamento de Física
Doctorado en Ciencia con Mención en Física