Researchers have wondered why so few particles of antimatter are found in the universe despite the fact that matter and antimatter were created in equal amounts at the instant of Big Bang. One explanation was that antimatter probably lacked the same attractive force as matter. However, Kefeng Xin, a graduate student at Rice University, along with a team of researchers, measured the scattering length and the effective range of interaction between two antiprotons. They discovered that the scattering length of antiprotons was roughly 7.41 femtometers, and the effective range was 2.14 femtometers. This means antiprotons have the same attractive force as protons. This is the first time the forces between antimatter particles have been measured.
Read more in Science Daily.