This is a lecture from Dr Feinstein's 4th-year module G14FUN Functional Analysis. See also Dr Feinstein's blog at http://explainingmaths.wordpress.com/ and, in particular, the Functional Analysis screencasts blog page at http://wp.me/PosHB-8v In this screencast, Dr Feinstein discusses two famous results concerning collections of bounded linear operators, one of which is a corollary of the other. Both of these results have been called the Banach-Steinhaus Theorem (by various authors). The st

Level 3 Mathematics

The Uniform Boundedness Principle - Dr Joel Feinstein

This video is a combination of the three screencasts from Chapter 9 of the second year module G12MAN Mathematical Analysis, lectured by Dr J. Feinstein (Nottingham). See also Dr Feinstein's blog at http://explainingmaths.wordpress.com/ and, in particular, the associated blog post at http://wp.me/posHB-7j The aim of this material is to introduce the student to two notions of convergence for sequences of real-valued functions. The notion of pointwise convergence is relatively straightforward, bu

Uniform convergence and Pointwise convergence

This is a lecture on the properties of open sets in finite-dimensional Euclidean space by Dr Joel Feinstein from his second-year module on Mathematical Analysis. This material is suitable for those who already know the definitions of open set and of the interior of a set in finite-dimensional Euclidean space. In this session Dr Feinstein shows that finite unions and intersections of open sets are open, and then discusses infinite unions and intersections. It turns out that infinite unions of o

Properties of open sets - Dr Joel Feinstein

This popular maths talk by Dr Joel Feinstein gives an introduction to various different kinds of infinity, both countable and uncountable. These concepts are illustrated in a somewhat informal way using the notion of Hilbert's infinite hotel. In this talk, the hotel manager tries to fit various infinite collections of guests into the hotel. The students should learn that many apparently different types of infinity are really the same size. However, there are genuinely "more" real numbers than the

Beyond Infinity? Dr Joel Feinstein

This is a lecture from Dr Feinstein's 4th-year module G14FUN Functional Analysis. See also Dr Feinstein's blog at http://explainingmaths.wordpress.com/ and, in particular, the associated blog post at http://wp.me/posHB-7y In this screencast, Dr Feinstein proves the Baire Category Theorem for complete metric spaces - a countable intersection of dense, open subsets of a complete metric space must be dense. This material is suitable for those with a knowledge of metric space topology and, in p

The Baire Category Theorem - Dr Joel Feinstein

This is the final lecture of the second-year module G12MAN Mathematical Analysis, as taught by Dr Joel Feinstein. This lecture gives a brief introduction to Riemann integration. This material is motivated in terms of questions of antidifferentiation and area. The proofs of the lemmas and theorems are not included here (see books for details), but the main definitions are given in full, along with illustrative examples and diagrams, and the statements of the main theorems. Material discussed inclu

An introduction to Riemann integration - Dr Joel Feinstein

A selection of recordings suitable for third-year mathematics undergraduate students at university.