the hunt for the god particle

Guardian | We have all heard of 'dark matter'. But what about dark galaxies, dark planets - even dark people? Particle physicists have a problem, he says. They are an anthropocentric bunch, too preoccupied with the particles and forces that impinge on humanity. They have spent so much time unravelling mysteries such as the structure of atoms and why the sun shines that they have neglected other avenues of inquiry. They need to broaden their horizons, Wells says. To think beyond the world we see and touch.

If that was the stick, next came the carrot. Our knowledge of the cosmos tells us that the stuff around us, from plants and people to stars and planets, is made from just a handful of elementary particles. On top of these, there is a small number of forces that make nature run smoothly, doing things like keeping planets in their orbits and ensuring everyday objects don't suddenly collapse into a pile of atoms. But how do we know, asks Wells, that there isn't much more going on than this? Our knowledge of nature and how it works is based on observations. What if we can't see everything? What might we be missing out on? There could be a "hidden world" out there, Wells says, where particles and forces are busily at work, all around us, but beyond the realm of our senses.

The phrase "hidden world" sounds like a science-fiction cliche, but it simply means that there may be more particles and forces at work in the world – and the cosmos at large – than those we see when we look around. They are so aloof, so hidden from our daily experience, that they go completely unnoticed.

"It would be strange if we were so special that we could feel and observe everything that is going on out there," says Wells, who is one of a growing number of physicists working on the hidden worlds idea. "We are lumps of clay swirling on a little blue marble in an overwhelming vastness of universe. We have to envision that there is more going on. There really should be additional particles and forces," he says.