Article

Understanding uncertainty: A 113% chance of death?

A recent study from Harvard reported that eating red meat is associated with a 13% increased risk of death. But what does this mean? Surely our risk of death is already 100%, and a risk of 113% does not seem very sensible? To really interpret this number we need to use some maths.
Article

Outer space: Rowing has its moments

If you look at the pattern of rowers in a racing four or eight rowing boat then you expect to find them positioned in a symmetrical fashion, alternately right-left, right-left as you go from one end of the boat to the other. However, the regularity of the rower's positions hides a significant asymmetry that affects the way the boat will move through the water.
Collection

Teacher package: Rational and irrational numbers

This teacher package is devoted to the number line and the two major classes of numbers it's divided into: rational numbers, which can be written as fractions, and irrational numbers, which are everything else.
Article

Mapping the mind's eye

Recent discoveries have made it possible to control computer games by thought alone, or work out what kind of item someone is thinking about from their brain signals. And that's not all. Researchers were able to use brain scans to reconstruct what someone was looking at. In these experiments the scientists were literally able to see what people were thinking. A worrying thought, perhaps. But how did they do it?
Article

Sex, evolution and parasitic wasps

Some things are so familiar to us that they are simply expected, and we may forget to wonder why they should be that way in the first place. Sex ratios are a good example of this: the number of men and women in the world is roughly equal, but why should this be the case? A simple mathematical argument provides an answer.
Article

Bridges, string art and Bézier curves

The Jerusalem Chords Bridge, Israel, was built to make way for the city's light rail train system. Its design took into consideration more than just utility — it is a work of art, designed as a monument. Its beauty rests not only in the visual appearance of its criss-cross cables, but also in the mathematics that lies behind it. So let's take a deeper look at it.
Podcast

Probing the dark web

Networks loomed large at the AAAS annual meeting in Vancouver, in particular the one you're looking at right now: the Internet. Plus went along to a session on web surveillance. It sounds sinister at first, but as we found out, it's not all about Big Brother breaching your privacy. Information on the web can help us catch terrorists and criminals and it can also identify a widespread practice called astroturfing.
Article

Having fun with unit fractions

The number 1 can be written as a sum of unit fractions, that is fractions with 1 in the numerator. But how long can we make such a sum?
Article

Bang, crunch, freeze and the multiverse

Some of the things I overheard at Stephen Hawking's 70th birthday conference did make me wonder whether I hadn't got the wrong building and stumbled in on a sci-fi convention. "The state of the multiverse". "The Universe is simple but strange". "The future for intelligent life is potentially infinite". And — excuse me — "the Big Bang was just the decay of our parent vacuum"?!