Continuous deformations of Fredholm operators in B(H)

Let X be a compact Hausdorff topological space. The K-group of X, denoted by K(X), is the Grothendieck group associated to the commutative monoid of isomorphism classes of complex vector bundles over X, equipped with the Whitney sum. Let H be an infinite dimensional Hilbert space and F(H) be the set...

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Detalles Bibliográficos
Autor: Dias, Rodrigo Lima
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2021
País:Brasil
Institución:Universidade de São Paulo (USP)
Repositorio:Biblioteca Digital de Teses e Dissertações da USP
Idioma:inglés
OAI Identifier:oai:teses.usp.br:tde-09082021-231927
Acceso en línea:https://www.teses.usp.br/teses/disponiveis/45/45131/tde-09082021-231927/
Access Level:acceso abierto
Palabra clave:Fredholm index
Fredholm operators
Index theory
Índice de Fredholm
K-teoria
K-teoria de espaços compactos
K-theory
K-theory of compact spaces
Operadores de Fredholm
Teoria do índice
Descripción
Sumario:Let X be a compact Hausdorff topological space. The K-group of X, denoted by K(X), is the Grothendieck group associated to the commutative monoid of isomorphism classes of complex vector bundles over X, equipped with the Whitney sum. Let H be an infinite dimensional Hilbert space and F(H) be the set of Fredholm operators on H. The Atiyah-Jänich Theorem states that the families-index is a natural isomorphism between the monoid of homotopy classes of functions from X into F(H) and the group K(X). In case X is a singleton, the families-index is the classic Fredholm index, and the Atiyah-Jänich Theorem states that the arcwise connected components of F(H) are characterized by the Fredholm index. In this work, we give a detailed exposition of the Atiyah-Jänich Theorem, studying the necessary elements to understand the construction of the K-group of a compact Hausdorff topological space, the definition of the families-index and giving a proof that such an index is the mentioned isomorphism.