RT Dissertation/Thesis T1 Bach-flat manifolds and conformally Einstein structures A1 Gutiérrez Rodríguez, Ixchel Dzohara K1 Bach tensor K1 Conformally Einstein manifolds K1 Ricci solitons AB Einstein manifolds, being critical for the Hilbert-Einstein functional, are central in Riemannian Geometry and Mathematical Physics. A strategy to construct Einstein metrics consists on deforming a given metric by a conformal factor so that the resulting metric is Einstein. In the present Thesis we follow this approach with special emphasis in dimension four. This is the first non-trivial case where the conformally Einstein condition is not tensorial and there are topological obstructions to the existence of Einstein metrics. The conformally Einstein condition is given by a overdetermined PDE-system. Hence the consideration of necessary conditions to be conformally Einstein are of special relevance: the Bach-flat condition is central. In this Thesis we classify four-dimensional homogeneous conformally Einstein manifolds and provide a large family of strictly Bach-flat gradient Ricci solitons. We show the existence of Bach-flat structures given as deformations of Riemannian extensions by means of the Cauchy-Kovalevskaya theorem. YR 2019 FD 2019 LK http://hdl.handle.net/10347/19468 UL http://hdl.handle.net/10347/19468 LA eng DS Minerva RD 6 jun 2026