Testing the cosmological model using galaxy voids

This thesis studies the accelerated expansion of the universe using regions where the number density of galaxies is smaller than the average cosmological density. These cosmic voids are used to test the expansion rate of the universe from a geometrical perspective, by considering them as idealised spheres, and from a dynamical perspective, where galaxy positions and velocities are coupled to generate growth of structure in the surroundings of the void. This work presents these analyses using data from one galaxy survey and computer simulations in addition to develop a forecast for applying this technique for future galaxy surveys.