# Numbers

## Inaugural Lecture, Professor Paul Flavell

Professor of Pure Mathematics
Head of School of Mathematics

Location Lecture Theatre A, Watson Building (R15 on the map), followed by a drinks reception Thursday 18 May (5:15pm)

## Synopsis

Gauss is widely regarded as the greatest mathematician who ever lived. In his doctoral thesis, he proved the Fundamental Theorem of Algebra namely:

The output of any non-constant polynomial function can be any number.

We will prove this result. The first step in doing so will be to understand the vocabulary – in particular, what a number is. We’ll focus on the idea of a number being used to measure things, so we’ll start with whole numbers, which can be used to measure how much money we have. Moving on, we introduce fractions and numbers like the square root of two to get the real numbers. These can be used to represent distances, temperature, DC voltages and so on.

In order to prove the Fundamental Theorem of Algebra, we need to go further and introduce Complex Numbers. What do these measure?

The lecture will conclude with a geometric proof of the Fundamental Theorem.

Complementary alcoholic and non-alcoholic drinks will be served at the drinks reception following the event. Alcoholic drinks will be only be served to those who are aged 18 or over.

• Name