Math 7338
Functional Analysis
Instructor: Michael Loss
Lectures: TTh 9:35-10:55pm
Location:
Skiles 156
Office
hours: T,Th 12-1pm, or by appointment
Textbook: Introductory
Functional Analysis with Applications, by Erwin Kreyszig, Wiley
Functional
Analysis is the synthesis between linear algebra and analysis. It
has its origins in the work of mathematicians like Vito Volterra
(1860 - 1940)
and
Eric Ivar Fredholm (1866-1929) on integral equations and was
developed by the School around David Hilbert (1862 - 1943) and
especially by the School around Stefan Banach (1892 - 1945) and Hugo
Steinhaus (1887 -1972). The power of functional analysis is due to
the fact
that
many problems like solving partial differential equations can be
formulated in functional analytic terms. Such problems cannot be
solved in terms
of a
closed involving elementary functions. One always creates a sequence
of functions and then shows that this sequence converges to the
desired solution.
For
this one needs a function space in which one expects to solution to
be and a topology. Function spaces while linear spaces have the
unpleasant property
that
most of them are infinite dimensional. This is where the analysis
comes in.
While
function spaces are the way to go in many applications, one can look
at common feature and proceed in an abstract fashion. The key notion
here is
completeness and this notion allows to prove a number of general
statements, like the uniform boundedness principle, the open mapping
theorem and the
closed graph theorem. Further, Functional Analysis gives a framework
in which many problems in applied mathematics can be formulated. An
example
is
the Fredholm alternative for solving integral equations or the
Neumann series.
Functional analysis is the starting point of fairly deep mathematics
such as Banach Algebras and C*-algebras. I may make a few remarks
about these topics.
A
prerequisite of the course is analysis at least on the level
of undergraduate analysis so that you are familiar with notions like
metric spaces, normed spaces,
open
sets, closed sets, Cauchy Sequences, Completeness etc..
Here
is a list of topics that I plan to cover in this course:
Normed spaces and linear operators, Hilbert spaces and linear
operators on Hilbert spaces, Banach spaces and linear operators on
Banach spaces,
the
fundamental theorems: Hahn-Banach Theorem, Uniform Boundedness
Theorem, Open Mapping Theorem and the Closed Graph Theorem,
Compact operators, Spectral theory of bounded self-adjoint
operators.
Here
is a rough timeline with an approximate number of lectures devoted
to each topic:
Chapter 2. Normed spaces and Banach spaces: 3 lectures,
Chapter 3. Inner product spaces and Hilbert spaces: 3 lectures
Chapter 4.
Fundamental theorems for normed and Banach spaces: 5 lectures
Chapter 5. Banach fixed point theorem and its application to
differential equations: 3 lectures
Chapter 7. Spectral theory of linear operators in normed spaces: 3
lectures
Chapter 8. Compact linear operators on normed spaces and their
spectrum: 5 lectures
Chapter 9. Spectral theory of bounded self-adjoint linear operators:
5 lectures
Grades:
There will be homework and a final exam. The homework will count 70%
and
the final exam 30%. [100%, 90%] of the course work
yields the grade A,
(90%,
80%] yields the grade B, (80%, 60%] yields the grade C, (60%, 50%]
yields the grade D and below 50%
of
the course work yields the grade F.
Homework 1, due Tuesday September 10.
Homework 2, due Thursday October 3.
Homework 3, due Thursday October 23
Homework 4, due Thursday November 14
Homework 5, due Tuesday November 26
Final Exam