Observable universe

Even though the Big Bang happened 13.7 billion years ago, and no object can move faster than the speed of light, the diameter of the known universe is at least 46 billion light years. It is because the expansion of the universe itself can occur faster than the speed of light. Particles cannot travel faster than the speed of light since if a particle has mass then it takes an infinite amount of energy to pass the speed of light. Space-time has no such limitation.