Physicists say they have all but proven that the ‘God particle’ exists. They have a footprint and a shadow, and the only thing left is to see for themselves the elusive subatomic particle believed to give all matter in the universe size and shape.

Scientists at the world’s biggest atom smasher plan to announce Wednesday that they have nearly confirmed the primary plank of a theory that could restructure the understanding of why matter has mass, which combines with gravity to give an object weight.

The idea is much like gravity and Isaac Newton’s discovery: It was there all the time before Newton explained it. But now scientists know what it is and can put that knowledge to further use.

The focus of the excitement is the Higgs boson, a subatomic particle long sought by physicists.

Researchers at the European Organization for Nuclear Research, or CERN, say that they have compiled vast amounts of data that show the footprint and shadow of the particle, even though it has never actually been glimpsed.

But two independent teams of physicists are cautious after decades of work and billions of dollars spent. They don’t plan to use the word ‘discovery.’ They say they will come as close as […]