Değişken Kozmolojik Sabite Sahip Evren Modellerinde Parçacık ve Olay Ufkunun İncelenmesi

Abstract

The concepts of dark energy and dark matter, which have an important role in the work of the modern universe models within the scope of the presented thesis, are important issues that should be given priority in cosmology research. It is an undeniable fact and necessity to take into account the dark energy in the creation of the right models that match the observations. The magnitude of the cosmological constant that can be associated with Dark Energy, and its temporal behavior in homogeneous and isotropic universe models is an issue that needs to be illuminated in the light of all these facts. In the proposed thesis study, it is envisaged to examine the particle and event horizon, which can give important clues in determining the age of the universe, in the models of the universe with variable cosmological constant. It is thought that the calculation of the particle and event horizon in the universe models represented by different equations than the conventional form of the universe models in the new studies that emerged with the handling of the cosmological constant associated with dark energy depending on the time. It is clear that the comparison of these results will shed light on the spatial and temporal behavior of dark energy, which plays an important role in cosmology research. It is also thought that the results to be obtained will contribute to the understanding of the cosmological constant problem, which has an important place in cosmology.