Álgebras de Clifford e a fibração de Hopf / Clifford algebras and the Hopf fibration
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
Spin groups come in many forms in Mathematics and Mathematical Physics, having great importance in the theory of fiber bundles and differential operators defined on them. The concept of spin structure is derived from them, being the basis of all a theory, known as spin geometry. This thesis introduces the first concepts necessary for the study of such groups, as well as important aspects related to them. Given the nature of the Spin groups and problems which they re related to, several topics at the interface between algebra and geometry had to be addressed. At first, we studied Clifford algebras, their twisted adjoint representation and Spin groups as subgroups of the group of units of such algebras. Followed these studies a detailed analysis of the theory of covering spaces and the classification of them. Done that, we were able to understand the group Spin, via the twisted adjoint representation, as the universal covering space of the special orthogonal group of a non-degenerate quadratic space. From there, we focused on the theory of principal bundles and their relationship with the geometric properties of manifolds on which they are built. To summarize what was studied, we algebraically construct the Hopf fibration at the end of this thesis, explaining its relationship with the spin structure of the sphere S².