Resumen de How ghosts stole gravity's strength
Ghostly particles could be haunting the universe. A new theory claims that the cosmos is full of unseen particle families that don't interact with each other. If true, the model could explain why gravity is so puzzlingly weak. The idea is an alternative to supersymmetry, a theory in which every known particle has a heavier partner. Such superparticles would keep the mass of their partners low enough to account for gravity's weakness. But the particle-smashing Large Hadron Collider, near Geneva, Switzerland, still hasn't seen any superparticles, despite years of searching.
