Ponente
Descripción
Total density of the Universe is very close to the critical density; that is, the matter-energy content is exactly that required in the Universe to be flat. This strange coincidence ('flatness problem') has not yet been explained, as well as the nature of dark energy, which compensates the gavitational force caused by the matter. To explain the origin of the dark energy, this works uses a space-time whose expansion does not depend on the matter-energy content (Monjo 2017, 2018). From a topological viewpoint, it is possible to apply an homeomorphism between an expanding 3-sphere (hypercone) and a flat spacetime. If an observer is added to measure distances from the expanding and positively curved timespace, a radial deformation of the distances is found. This deformation becomes an apparent acceleration when a family of stereographic projections is applied to the flat manifold. Comparing with the standard model, a predicted value of the dark energy density (Omega_L = 0:6937181(2)) is obtained from the unique real solution of the stereographic projections when the arc length is used. References: Monjo, R. (2018). Geometric interpretation of the dark energy from projected hyperconical universes. Physical Review D 98, 043508 (LS16206D). DOI: 10.1103/PhysRevD.98.043508. arXiv:1808.09793. Monjo, R. (2017). Study of the observational compatibility of an inhomogeneous cosmology with linear expansion according to SNe Ia. Physical Review D 96, 103505. DOI: 10.1103/PhysRevD.96.103505. arXiv:1710.09697.
