In issue 29 of Plus, we heard how a simple mathematical equation became the subject of a debate in the UK parliament. Chris Budd and Chris Sangwin continue the story of the mighty quadratic equation.

All of science can be regarded as motivated by the search for rules behind the randomness of nature, and attempts to make prediction in the presence of uncertainty. Chris Budd describes the search for pattern and order in chaos.

Scientists have for the first time measured the speed of gravity and tested Einstein's assumption - or have they?