Gamma-ray observations shrink known grain size of spacetime

Smaller dots, Georges, please. In their efforts to unify quantum theory and gravity, theoretical physicists have likened spacetime to a Georges Seurat painting, composed of tiny dots or lumps that meld to form a seemingly smooth picture. But if spacetime really does have a grainy structure on the smallest scales, the cosmic painter may need to get finer brushes, a new study reveals.