*Watch Online/In person*: The path traced out by a given point on the rim of a circle as you roll it along a straight line is a beautiful curve called a cycloid, whose appeal to mathematicians has had it dubbed “the Helen of Geometry”. This curve is known in geometry as a roulette, which is a curve you get by rolling one curve along another, and there are many more with an amazing range of applications, from clockwork toys to nuclear reactors.
Professor Sarah Hart is the first woman Professor of Geometry at Gresham College, and was appointed in 2020. She is Professor of Mathematics and until recently was Head of Mathematics and Statistics at Birkbeck, University of London. She studied at Oxford and Manchester, gaining her PhD in 2000. Postdoctoral research and teaching followed, including a prestigious Engineering and Physical Sciences Research Council Fellowship, before she was appointed to a lectureship at Birkbeck in 2004