Is the Universe finite or infinite? Is there infinity inside a black hole? Is space infinitely divisible or is there a shortest length? We talk to philosophers and physicists to find out.

Is poker a game of psychology and cunning rather than strategy? We investigate the maths of bluffing.

A commonly held belief about medieval Europe is that academic pursuits had fallen into a dark age. The majority of scholars were churchmen, and their enquiry often related to some principle of church practice. But is there a value to respecting the tenacity of historic mathematicians?

In February this year we were lucky enough to interview Freeman Dyson at the Institute for Advanced Studies in Princeton, USA. Dyson is now 89 and still does physics every day in his first floor office at the Institute. Here is an edited version of our interview that we hope conveys his generous nature, wit and intellect.

This is the second article in our four-part series exploring quantum electrodynamics. After successfully applying quantum mechanics to the electromagnetic field, physicists faced a problem of boundless proportions: every calculation they made returned infinity as the answer.

This is the last article in a four-part series exploring quantum electrodynamics. After a breakthrough that tamed QED in theory, the stick-like drawings known as Feynman diagrams, policed by a young Freeman Dyson, made the theory useable.