What does the Big Bang Theory say?
The Big Bang Theory says that the observable universe began in the explosion of a superdense ball of matter.
The theory says that the universe had a beginning. This implies that the observable universe is not eternal or self existent.
The empirical evidence indicates that as well as having a beginning will have an ending. The evidence indicates that the universe is an open system.
The philosophical implications of the Big Bang and theory and open nature of the universe is that matter and energy are not eternal and that must exist something besides matter and energy.