I was going to post about creating videos but will save that for another day (I have a long video to watch first!). Instead I’ll post about the petition to put Alan Turing on the 10 pound note. The last e-petition concerning Turing – to grant him a pardon – has yet to succeed. This is mainly because it’s a general principle in this country that someone can’t be pardoned simply because the act is no longer criminal. This new petition probably has a greater chance of success. It’s not a certainty, scientists have been well-represented on our notes, for example Newton, Faraday, Nightingale and Darwin, but as Darwin is currently on the 10 HM Treasury may in the interest of balance opt for a non-scientist for that note. You can sign the petition here:...

## Willmore Day at Durham...

posted by Kevin Houston

Last week’s Yorkshire Durham Geometry Day, held at Durham, celebrated the work and life of Tom Willmore. Willmore was a differential geometer who spent most of his academic career at the University of Durham. As I was giving a talk in a school I missed the first two talks of the day which was a shame as the first explained a recent proof of the long-standing Willmore Conjecture. For a surface we can define the notion of curvature in a number of ways. For Willmore surfaces we use mean curvature so let’s define that. At a point of a surface take a normal vector. Any non-zero vector in the line perpendicular to the tangent plane to the surface will do. Next take any plane that contains this normal. The intersection of this plane with the surface is a curve. Take the curvature of this curve at the point , call this curvature . (The curvature of a curve at a point is where is the radius of the circle that best approximates the curve at that point.) Next take the plane containing the normal that is at right angles to the first one. We get another curve and hence another curvature, call it . Take the mean of these two curvatures, . This is the mean curvature at ; we will denote it by . We can do this at every point and so we get a function given by . An alternative viewpoint is given on the Wikipedia page. Now we integrate the square of this function over the whole of the surface. The Willmore energy of a surface , denoted , is the number . That is we integrate over the whole surface the square of the mean curvature. So for every...

## Hey, it’s Pi Day!...

posted by Kevin Houston

As someone associated with the Tauists (a Times editorial described me as a leader of a maverick band of mathematicians promoting tau) I shouldn’t be celebrating Pi Day today. But Tauists and Piists can live in peace as the following link shows (and from which the above picture is taken): http://mitadmissions.org/blogs/entry/i-have-smashing-news Now, if you’ll excuse me I need to rush off to give a talk about card cheating in a local school and then go to Durham for a Yorkshire Durham Geometry Day celebrating the life of Tom...

## Recipe for Pi Day

posted by Kevin Houston

International Pi Day is approaching (14th March) and the world is looking for exciting recipes for pies to celebrate such an important date in the calendar. Well, here’s a great idea. They are called “Tau-nados”. In order to get the pun one has to pronounce tau in the English way (“tor”) rather than the American way (sounds like cow). The idea is that you get two pies in one – hence the tau from 2 pi. And not only that the pies are twisted to form a double helix! See the website http://www.instructables.com/id/Tau-nados/ for the recipe. Here’s a taster of what they look like: Thanks to Joseph Lindenberg for bringing this to my...

## Updates and my upcoming talks...

posted by Kevin Houston

Last week was another busy week with trips to London and Birmingham. The latter was to give a talk at the annual National Association of Mathematical Advisers. This is a group of people who advise school teachers and politicians regarding the content and implementation of Primary, Secondary, GCSE and A Level Mathematics. (Probably, that’s a gross distortion of what they do but it’ll give you the idea if you’ve never heard of them before.) My talk was on How to Think Like a Mathematician. I’m not sure that it was the sort of talk they were looking for but I gave it a go… On the Thursday evening there was a conference dinner followed by the comedian Helen Keen who was doing her It is Rocket Science talk. It was certainly an enjoyably funny show but maybe a bit short – though that could be because she speaks so fast. Nonetheless, she is worth watching – according to her website she will speaking at the Cambridge Science Festival this month. Which brings me to the Leeds Festival of Science, and in particular, my talks. I’ll be speaking 1:30-2:30 on Saturday 10 March and Wednesday March 28th. See the Festival Science brochure and the WP Milne poster for...