Functional analysis (spring 2025)

Lecturer: Eduard Ortega

Lectures

  • Tuesdays 10:15-12:00 in Realfagbygget R51
  • Thursdays 12:15-14:00 in Realfagbygget R51
  • First Lecture Tuesday 7th January from 10:15-12:00 in Realfagbygget R51

Office hours

  • By appointment.

Reading materials

A. Bowers and N.J. Kalton An Introductory Course in Functional Analysis

Also see Harald Hanche-Olsen's notes and, E. Lieb and M. Loss. Analysis. Graduate Studies, AMS, for a more elementary approach to L^p-spaces, duality of L^p-spaces and related material on Lebesgues spaces that we are going to discuss during the first weeks.

Lectures log

Week Description Comments Recomended exercises
week 2 Chapter 1 in Bowers & Kalton Review of basic notions on normed spaces. Topology on metric spaces. Baire category theorem
week 3 Chapter 4 Bowers & Kalton Uniform Boundedness Principle and Banach-Steinhaus theorem. Fourier series. 4.2, 4.6 and 4.9
week 4 Chapter 4 Bowers & Kalton The open mapping theorem and Closed graph theorem 4.19, 4.20 and 4.21
week 5 Chapter 2 Bowers & Kalton Dual spaces of \(\ell_p\) spaces and function spaces of measure spaces \(L_p(\Omega,\mu)\) 2.1 and 2.2
week 6 Chapter 3 Bowers & Kalton Sublinear functionals. Hahn-Banach extensions theorems.
week 7 Chapter 3 Bowers & Kalton Invariant Hahn-Banach theorem. Haar measure of compact abelian groups 3.1, 3.9, 3.10 and 3.11
week 8 Chapter 3 Bowers & Kalton Reflexive spaces. Adjoint of operators
week 9 Chapter 3 Bowers & Kalton Direct sums of Banach spaces. Quotients of Banach spaces
week 10 Chapter 5 Bowers & Kalton Topological spaces
week 11 Chapter 5 Bowers & Kalton Topological vector spaces. Basis of balanced and absorbent open sets of 0.
week 12 Chapter 5 Bowers & Kalton The geometric Hahn-Banach theorem
week 13 Chapter 5 Bowers & Kalton The weak topologies. Weak convergent sequences. The weak *-topology. The Banach Alaoglu theorem.
week 14 Chapter 6 Bowers & Kalton Compact operators on Banach spaces. Rank-Nullity theorem
week 15 Chapter 7 Bowers & Kalton Hilbert spaces. Compact operators on Hilbert spaces

Exam

The Exam will take place the 19th May. You are NOT allowed to take notes or books. The Exam will consist of 5 questions, each of them with the same value.

3 of this questions will be about the main theorems and concepts of the course.

2 questions will be a selection of the exercises in the book A. Bowers and N.J. Kalton An Introductory Course in Functional Analysis.

Selected exercises: 2.1, 2.14, 3.4, 3.5, 3.16, 4.1, 4.4, 4.6, 4.12, 4.21, 5.9, 5.20, 5.31, 5.35, 6.1, 6.11

2025-04-24, Eduardo Ortega Esparza