Welcome to Plus magazine!

Presents

Plus magazine opens a door to the world of maths, with all its beauty and applications, by providing articles from the top mathematicians and science writers on topics as diverse as art, medicine, cosmology and sport. You can read the latest mathematical news on the site every week, browse our blog, listen to our podcasts and keep up-to-date by subscribing to Plus (on email, RSS, Facebook, iTunes or Twitter).

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"?!

Most of us think that we have the capacity to act freely. Our sense of morality, our legal system, our whole culture is based on the idea that there is such a thing as free will. It's embarrassing then that classical physics seems to tell a different story. And what does quantum theory have to say about free will?

This is the first part of the lecture given by Astronomer Royal Martin Rees at Stephen Hawkings birthday symposium.

Human reasoning is biased and illogical. At least that's what a huge body of psychological research seems to show. But now a psychological scientist from the University of Toulouse in France has come up with a new theory: that logical and probabilistic thinking is an intuitive part of decision making, only its conclusions often lose out to heuristic considerations.

Researchers in Germany have created a rare example of a weird phenomenon predicted by quantum mechanics: quantum entanglement, or as Einstein called it, "spooky action at a distance". The idea, loosely speaking, is that particles which have once interacted physically remain linked to each other even when they're moved apart and seem to affect each other instantaneously.

"It's a great day for particle physics," says Ben Allanach, a theoretical physicist at the University of Cambridge. "It's very exciting, I think we're on the verge of the Higgs discovery." And indeed, it seems like the Large Hadron Collider at CERN has given particle physics an early Christmas present — compelling evidence that the famous Higgs boson exists.

It's Stephen Hawking's 70th birthday this week and the University of Cambridge is celebrating with a conference in his honour. If it's going to be as exciting as his 60th birthday, and it definitely looks like it will, then we're in for a treat! We'll be giving you articles and podcasts from the conference soon, but in the meantime, here's what we did for his 60th.

What's a multiverse? What's the future for intelligent life? And what happened 380,000 after the Big Bang. Find out in these interviews with the physicists David Spergel and Raphael Bousso, who we spoke to during Stephen Hawking's 70th birthday conference.

Structural joint in T5

A quick postcard from Plus' temporary Cambridge/Boston office!

Richard Elwes' Maths handbook is a lucid presentation of basic mathematics facts. It is intended for those who "were never any good at mathematics", for grown-ups who wish they remembered more of the maths they studied as children, or those who are intimidated by the subject. It is the latter point the author is most passionate about. This book serves as a proof that mathematics is a very natural way of thinking, and there is a reason for everything in it.

"Astronomers are used to large numbers, but few are as large as the odds I'd have given this celebration today," is how Astronomer Royal Martin Rees started his presentation at Stephen Hawking's birthday symposium yesterday. He was talking about the 1960s when he first met Hawking who was then already suffering motor neurone disease. But Rees' prediction has been proved wrong. Hawking turned 70 yesterday and since the time of their first meeting he has made enormous contributions to cosmology and physics.