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In this thesis, we aim to understand the microscopic details and origin ofthe Cosmological Horizon, produced by a static observer in four-dimensional deSitter (dS$_4$) spacetime. We consider a deformed extension of dS spacetime bymeans of a single $\mathbb Z_q$ quotient, which resembles an Orbifold geometry.The Orbifold parameter induces a pair of codimension two minimal surfaces givenby 2-spheres in the Euclidean geometry. Using dimensional reduction on thetwo-dimensional plane where the minimal surfaces have support, we use theLiouville field theory and the Kerr/CFT mechanism in order to describe theunderlying degrees of freedom of the Cosmological Horizon. We then show, thatin the large $q$-limit, this pair of codimensions two surfaces can be realizedas the conformal boundaries of dS$_3$. We notice that the central chargeobtained using Liouville theory, in the latter limit, corresponds to theStrominger central charge obtained in the context of the dS/CFT correspondence.In addition, a formulation of entanglement entropy for de Sitter spacetimes isgiven in terms of dS holography and also a different approach in which theentanglement between two disconnected bulk observers is described in terms ofthe topology of the spacetime. Therefore, a quarter of the area formula isproposed, in which the area corresponds to the are of the set of fixed pointsof an $S^2/\mathbb Z_q$ orbifold.

de Sitter Entanglement and Conformal Description of the Cosmological Horizon