# Articles

The expression that (nearly) explained the Universe

**Sophie Butchart**finds mysterious patterns in the solar system
Outer space: Are the constants of nature really constant?Are the unchanging features of the Universe really unchanging?

Sine languageAs an electronic musician

**Oli Freke**has always been fascinated by sine waves, so much so that he's created a song based on them for the Geekpop festival, which is currently taking place on the Web. In this article he explores his song, touching on ancient Greek mythology, strange piano tunings and Johann Sebastian Bach.
Births and deaths in fluid chaosDescribing the motion of fluids is a huge and unsolved mathematical problem. There are equations that seem to describe it well, but their complete solution is way beyond reach. But could there be a simpler method? The physicist

**Jerry Gollub**tells*Plus*about a new discovery which combines experiment with sophisticated maths.
Understanding uncertainty: The many ways of spinning risk

Would you prefer a game with a 90% chance of winning, or one with a 10% chance of losing? You might scratch your head and say it's the same thing, and you'd be right, but research has shown that people's perception of risk is surprisingly vulnerable to the way it's presented. In this article **David Spiegelhalter** and **Mike Pearson** explore how risk can be spun and there's an interactive animation for you to have a go yourself.

Sundaram's SieveThe prime numbers are the atoms amongst the integers, and while we know that there are infinitely many of them, there's no general formula that generates them all.

**Julian Havil**looks at a little-known algorithm that sieves out all primes up to a given number, and which is astonishing in its simplicity.
Restoring profanityIn 1979 decorating work in a house in Vienna revealed a set of medieval frescoes depicting a cycle of songs by a 13th century poet, who was particularly fond of satirising the erotic relationships between knights and peasant maidens. The frescoes are of great historical significance, but they are badly damaged. In this article

**Carola Schönlieb**explores how mathematicians use the heat equation to fill in the gaps.
EditorialThese are busy times for Plus. Apart from celebrating our 50th issue by putting together a bumper collection of in-depth articles, news and reviews, we're also working on various special projects, some of which have already gone live, and some of which will reach you over the next few weeks and months. Here's a sneak preview of what's in store for 2009...

It's all in the detailThe computer animation used in movies and games is now so lifelike, it is very hard to believe that you are actually watching a surface built from simple shapes of triangles.

**Phil Dench**tells*Plus*how he uses mathematics to help bring these models to life.