Summary: Black holes... you know. Cosmic singularities that can contain the mass of billions of stars like our Sun. Where the pull of gravity is so strong, nothing, not even light can escape their fearsome grasp. They're the source of much discussion, indirect observation and science fiction speculation. But according to George Chapline from Lawrence Livermore National Laboratory in California, they don't exist. Instead we have dark energy stars, which are connected to that mysterious force accelerating the expansion of the Universe.
